interleukin-8 and Crohn-Disease

Inflammatory bowel diseases remain a significant chronic disease affecting children and adolescents. Although corticosteroids remain the standard form of therapy for many patients, an era of biological agents for therapy in inflammatory bowel diseases is upcoming with human trials using these agents now forthcoming. In addition, studies on maintenance of remission are beginning to address the selection of those patients most likely to benefit from aminosalicylate therapies, the risks of relapse from using cyclooxygenase inhibitors, the lack of benefit from lipoxygenase inhibitors, and possible future methodologies to examine the effectiveness of the immuno-suppressive agent 6-mercaptopurine. Further development of the hypothesis that new-onset disease may be different than longstanding disease can be appreciated with reports of cytokine analysis in new-onset inflammation and the high risk of progression of disease in new-onset ulcerative proctitis in children. With more reports on the role of intestinal epithelial cells in intestinal diseases, it is now clear that this cell layer is not a passive bystander with regard to the interactions between the luminal contents and immune system components found within the lamina propria; new studies suggest that novel therapeutic strategies may be possible. This review summarizes recently reported aspects of Crohn's disease and ulcerative colitis, with an emphasis on issues-pertinent for younger patients.

Topics: Anti-Inflammatory Agents; Budesonide; Chemokine CXCL5; Chemokines, CXC; Chemotaxis, Leukocyte; Child; Colitis, Ulcerative; Crohn Disease; Humans; Interleukin-10; Interleukin-8; Nutritional Status

Topics: Colitis, Ulcerative; Crohn Disease; Cytokines; Humans; Interferon-gamma; Interleukin-1; Interleukin-2; Interleukin-6; Interleukin-8; Intestinal Mucosa; Sulfasalazine; Tumor Necrosis Factor-alpha

The risk of inflammatory bowel disease (IBD) is substantially heightened if patients' first-degree relatives have it. The genetic and immune factors related to the disease have attracted great attention, including patients innate genetic polymorphisms. Interleukin-8 (IL-8) plays a vital role in digestive-system diseases, especially in gastrointestinal diseases.. The study intended to explore the expression of interleukin-8 (IL-8) in the colon tissues of patients with Crohn's disease and the correlation between its polymorphisms and the disease's occurrence.. The research team performed a prospective study.. The study took place in the Department of Gastroenterology at Zhuji People's Hospital of Zhejiang Province in Zhuji, China.. Participants were 100 patients with Crohn's disease at the hospital between November 2016 and June 2018 and 100 healthy individuals. The research team assigned participants with Crohn's disease to the Crohn's disease group and the healthy participants to the control group.. The research team: (1) determined differences in the protein expression of the IL-8 between the groups; (2) examined the conformity of the data to that of the Hardy-Weinberg equilibrium; (3) analyzed the differences in the genotypes and alleles for the IL-8 single nucleotide polymorphisms (SNPs) rs102039, rs103284 and rs105432 between the groups; and (4) for the Crohn's disease group, examined the differences in the disease's location and behavior for the participants with different genotypes.. The protein expression level of IL-8 in the colon tissues in Crohn's disease group was significantly higher than that in control group (P < .05). The genetic association analysis showed significant correlations between the polymorphisms rs103284 and rs105432 and alleles of the IL-8 gene and the occurrence of Crohn's disease (P < .05), but no associations existed between the gene polymorphism rs102039 and alleles and Crohn's disease (P > .05). Significant correlations existed between the IL-8 gene polymorphisms rs103284 and rs105432 and the disease's location and behavior (P < .05).. IL-8 had a significantly increased expression in the colon tissues of the participants with Crohn's disease, and some genotypes and alleles for the gene polymorphisms rs103284 and rs105432 were significantly higher in the Crohn's disease group than in the control group. In addition, the disease's location and behavior were significantly different for participants in the Crohn's disease group with different genotypes.

Topics: Crohn Disease; Humans; Inflammatory Bowel Diseases; Interleukin-8; Polymorphism, Single Nucleotide; Prospective Studies

To examine the underlying mechanisms that lead growth impairment to occur more commonly in males than females with Crohn's disease (CD).. Children and adolescents with CD were enrolled in a prospective multicenter longitudinal cohort study. Height Z-score difference was computed as height Z-score based on chronological age (height chronological age-Z-score) minus height Z-score based on bone age (height bone age-Z-score) using longitudinal data. Specific serum cytokines were measured, hormone Z-scores were calculated based on bone age (bone age-Z), and their longitudinal associations were examined.. There were 122 children with CD (63% male) who completed 594 visits. The mean ± SD chronological age was 11.70 ± 1.79 years. The mean ± SD height chronological age-Z-score was -0.03 ± 0.99 in males and -0.49 ± 0.87 in females. The mean ± SD height bone age-Z-score was 0.23 ± 0.93 in males and 0.37 ± 0.96 in females. The magnitude of the mean height Z-score difference was greater in females (-0.87 ± 0.94) than males (-0.27 ± 0.90; P = .005), indicating growth was better in females than males. The following negative associations were identified: in females, interleukin (IL)-8 (P < .001) and IL-12p70 (P = .035) with gonadotropin-bone age-Z-scores; IL-8 (P = .010), IL-12p70 (P = .020), and interferon-γ (P = .004) with sex hormone-bone age-Z-scores, and IL-8 (P = .044) and interferon-γ (P < .001) with insulin-like growth factor 1-bone age-Z-scores; in males, IL-1 beta (P = .019) and IL-6 (P = .025) with insulin-like growth factor 1-bone age-Z-scores.. Our data suggest that sex-specific molecular pathways lead to growth impairment in children with CD (primarily growth hormone/insulin-like growth factor-1 axis in males and primarily hypothalamic-pituitary-gonadal axis in females). Mapping these sex-specific molecular pathways may help in the development of sex-specific treatment approaches targeting the underlying inflammation characteristic of CD.

Topics: Adolescent; Body Height; Child; Crohn Disease; Female; Growth Hormone; Human Growth Hormone; Humans; Insulin-Like Growth Factor I; Interferon-gamma; Interleukin-1beta; Interleukin-6; Interleukin-8; Longitudinal Studies; Male; Prospective Studies

The epidemiology of Crohn's disease (CD) has changed over the past decades, demonstrating a trend toward increased prevalence in developing countries, while in developed countries, its incidence has stabilized. The study aimed to examine the profile of the key pro-inflammatory cytokines in the serum of patients with CD and establish their association with the severity and activity of the disease.. A total of 61 patients (29 women (47.5%), 32 men (52.5%) aged from 18 to 40 years (mean age (30.42 ± 2.51) years) with the verified diagnosis of CD in the active phase were examined. The control group consisted of 30 healthy people of corresponding age.. CD is characterized by a reliable increase of pro-inflammatory cytokines in blood compared to healthy people: tumor necrosis factor-α (TNF-α) - by 4.45 times (137.46 ± 9.72 vs. 30.88 ± 2.08 pg/ml in healthy people, p < 0,001), interleukin-1α (IL-1α) - by 5.08 times (51.55 ± 4.36 vs. 10.14 ± 0.93 pg/ml, p < 0.001), interleukin-6 (IL-6) - by 2.16 times (20.03 ± 1.81 vs. 9.27 ± 0.52 pg/ml, p < 0.001), interleukin-8 (IL-8) - by 2.04 times (25.74 ± 2.05 vs. 12.62 ± 1.16 pg/ml, p < 0.001), and interferon-γ (IFN-γ) - by 5.30 times (208.63 ± 14.29 vs. 39.35 ± 2.40 pg/ml, p < 0.001). The authors have established direct correlations between the Crohn's disease activity index and blood content of TNF-α (r = 0.84, p < 0.013), INF-γ (r = 0.61, p < 0.028); between TNF-α and INF-γ content (r = 0.67, p < 0.023), IL-1α (r = 0.49, p < 0.042), IL-6 (r = 0.40, p < 0.045), and IL-8 (r = 0.51, p < 0.033); INF-γ and IL-1α (r = 0.53, p < 0.040), IL-6 (r = 0.37, p < 0.039), IL-8 (r = 0.44, p < 0.040).. Patients with CD were found to have multiple cytokines (TNF-α, IL-1α, IL-6, IL-8, and IFN-γ,). The content of cytokines correlated positively with the CD activity index.

Topics: Adult; Crohn Disease; Female; Humans; Interferon-gamma; Interleukin-6; Interleukin-8; Male; Severity of Illness Index; Tumor Necrosis Factor-alpha

Coronavirus disease 2019 (COVID-19) may lead to a severe inflammatory response referred to as a cytokine storm. We describe a case of severe COVID-19 infection in a recently diagnosed pediatric Crohn disease patient successfully treated with tumor necrosis factor-alpha (TNF-α) blockade. The patient presented with 5 days of fever, an erythematous maculopapular facial rash, and abdominal pain without respiratory symptoms. SARS-CoV-2 polymerase chain reaction was positive. Despite inpatient treatment for COVID-19 and a perianal abscess, the patient acutely decompensated, with worsening fever, tachycardia, fluid-refractory hypotension, elevation of liver enzymes, and transformation of the rash into purpura extending from the face to the trunk, upper and lower extremities, including the palmar and plantar surfaces of the hands and feet. Cytokine profile revealed rising levels of interleukin (IL)-6, IL-8, and TNF-α, higher than those described in either inflammatory bowel disease or severe COVID-19 alone. The patient was treated with infliximab for TNF-α blockade to address both moderately to severely active Crohn disease and multisystem inflammatory syndrome in children temporally related to COVID-19. Within hours of infliximab treatment, fever, tachycardia, and hypotension resolved. Cytokine profile improved with normalization of TNF-α, a decrease in IL-6, and IL-8 concentrations. This case supports a role for blockade of TNF-α in the treatment of COVID-19 inflammatory cascade. The role of anti-TNF agents in patients with multisystem inflammatory syndrome in children temporally related to COVID-19 requires further investigation.

Topics: Abnormalities, Multiple; Adolescent; Antirheumatic Agents; Betacoronavirus; Coronavirus Infections; COVID-19; Crohn Disease; Genetic Diseases, X-Linked; Humans; Ichthyosiform Erythroderma, Congenital; Infliximab; Interleukin-6; Interleukin-8; Limb Deformities, Congenital; Male; Pandemics; Pneumonia, Viral; SARS-CoV-2; Tumor Necrosis Factor-alpha

Pregnancy may affect the disease course of IBD. Both pregnancy and IBD are associated with altered immunology and intestinal microbiology. However, to what extent immunological and microbial profiles are affected by pregnancy in patients with IBD remains unclear.. Faecal and serum samples were collected from 46 IBD patients (31 Crohn's disease (CD) and 15 UC) and 179 healthy controls during first, second and third trimester of pregnancy, and prepregnancy and postpartum for patients with IBD. Peripheral blood cytokine profiles were determined by ELISA, and microbiome analysis was performed by sequencing the V4 region of the bacterial 16S rRNA gene.. Proinflammatory serum cytokine levels in patients with IBD decrease significantly on conception. Reduced interleukin (IL)-10 and IL-5 levels but increased IL-8 and interferon (IFN)γ levels compared with healthy controls were seen throughout pregnancy, but cytokine patterns remained stable during gestation. Microbial diversity in pregnant patients with IBD was reduced compared with that in healthy women, and significant differences existed between patients with UC and CD in early pregnancy. However, these microbial differences were no longer present during middle and late pregnancy. Dynamic modelling showed considerable interaction between cytokine and microbial composition.. Serum proinflammatory cytokine levels markedly improve on conception in pregnant patients with IBD, and intestinal microbiome diversity of patients with IBD normalises during middle and late pregnancy. We thus conclude that pregnancy is safe and even potentially beneficial for patients with IBD.

Topics: Adult; Case-Control Studies; Colitis, Ulcerative; Crohn Disease; Cytokines; Feces; Female; Gastrointestinal Microbiome; Humans; Interferon-gamma; Interleukin-10; Interleukin-5; Interleukin-8; Pregnancy; Pregnancy Complications; Pregnancy Trimesters

CD14+ mononuclear phagocytes [MNPs] and T cells infiltrate colon in ulcerative colitis [UC]. Here we investigated how CD14+ MNPs and the cytokines they produce shape the colonic effector T cell profile.. Colonic or mesenteric lymph node [mLNs] CD4+ T cells isolated from UC or Crohn's disease [CD] patients were stimulated with cytokines or autologous CD14+ MNPs. Cytokine expression was assessed by intracytoplasmic staining and multiplex ELISA. Unsupervised phenotypic multicolour analysis of colonic CD14+ MNPs was performed using the FlowSOM algorithm.. Among CD14+CD64+HLA-DR+SIRPα + MNPs, only the pro-inflammatory cytokine-producing CD163- subpopulation accumulated in inflamed UC colon and promoted mucosal IL-1β-dependent Th17, Th17/Th1, Th17/Th22 but not Th1 responses. Unsupervised phenotypic analysis of CD14+CD64+ MNPs segregated CD163- monocyte-like cells and CD163+ macrophages. Unexpectedly, IL-12, IL-1β and CD163-, but not CD163+, cells induced IL-8 expression in colonic CD4+ T cells, which co-expressed IFN-γ and/or IL-17 in UC and not CD. The CD163- monocyte-like cells increased the frequency of IL-8+IL-17+/-IFN-γ +/- T cells through IL-1β and IL-12. Finally, colonic IL-8+ T cells co-expressing GM-CSF, TNF-α and IL-6 were detected ex vivo and, promoted by IL-12 in the mucosa and mLNs in UC only.. Our findings established a link between monocyte-like CD163- MNPs, IL-12, IL-1β and the detection of colonic memory IL-8-producing CD4+ T cells, which might all contribute to the pathogenesis of UC.

Topics: Adolescent; Adult; Aged; Aged, 80 and over; Case-Control Studies; CD4-Positive T-Lymphocytes; Colitis, Ulcerative; Crohn Disease; Female; Humans; Interleukin-12; Interleukin-8; Intestinal Mucosa; Lipopolysaccharide Receptors; Male; Middle Aged; Young Adult

Inflammatory bowel disease (IBD) is a common disorder of chronic intestinal inflammation that can be caused by the disruption of intestinal immune homeostasis.. We aimed to evaluate the role of enhancer of zeste homolog 2 (EZH2) in the inflammatory response and explore the association between EZH2 and necroptosis in human epithelial colorectal adenocarcinoma cell lines.. In both in vitro and in vivo models, expression of EZH2 in intestinal tissues was verified by histology. The expression of inflammatory cytokines in cell lines treated with EZH2 siRNA with or without stimulus was analyzed by quantitative real-time polymerase chain reaction. An intestinal necroptosis cell model was established to elucidate whether EZH2 is involved in necroptosis.. Our present data indicated that EZH2 expression was decreased in in vitro and in vivo models and in patients with inflammatory bowel disease. EZH2 downregulation increased the expression of inflammatory factors, including TNF-α, IL-8, IL-17, CCL5, and CCL20 in a Caco-2 cell model. The JNK pathway was activated with the reduction of EZH2. In the necroptosis model, downregulation of EZH2 was detected with the upregulation of necroptotic markers RIP1 and RIP3. In addition, EZH2 knockdown with siRNA increased p-JNK and p-c-Jun.. Our data suggest that EZH2 plays an important role in the development of intestinal inflammation and necroptosis. Hence, EZH2 could be a potential therapeutic target for IBD.

Topics: Animals; Caco-2 Cells; Chemokine CCL20; Chemokine CCL5; Colitis; Colitis, Ulcerative; Crohn Disease; Dextran Sulfate; Down-Regulation; Enhancer of Zeste Homolog 2 Protein; Gene Knockdown Techniques; Humans; In Vitro Techniques; Inflammation; Inflammatory Bowel Diseases; Interleukin-17; Interleukin-8; Intestinal Mucosa; JNK Mitogen-Activated Protein Kinases; MAP Kinase Signaling System; Mice; Necroptosis; Nuclear Pore Complex Proteins; Phosphoproteins; Proto-Oncogene Proteins c-jun; Real-Time Polymerase Chain Reaction; Receptor-Interacting Protein Serine-Threonine Kinases; RNA-Binding Proteins; Trinitrobenzenesulfonic Acid; Tumor Necrosis Factor-alpha

Chemokine CCL14 is inactive in its proform. Here, we show that inflammation- and cancer-associated kallikrein-related peptidases KLK5 and KLK8 remove the N-terminal eight amino acids from the proform thereby converting CCL14 to its active state. Activity of the chemokine is demonstrated by migration of myeloid cells expressing relevant receptors.

Topics: Asthma; Atherosclerosis; Cell Line, Tumor; Chemokine CX3CL1; Chemokine CXCL12; Chemokines; Chemokines, CC; Crohn Disease; Enzyme Activation; Humans; Interleukin-8; Kallikreins; Leukemia; Macrophage Inflammatory Proteins; Pancreatitis; Reactive Oxygen Species

Primary non-response to infliximab in Crohn's disease is still incompletely understood. Our aim was to further characterize the role of inflammatory burden during infliximab induction therapy.. We studied a well-characterized cohort of 201 anti-TNF naive Crohn's disease patients treated with infliximab 5mg/kg at week 0, 2, 6 and 14 who had serum samples drawn just before every infusion. All serum samples were analyzed for CRP, albumin, TNF, IFN-γ, IL-6, IL-8, IL-10, infliximab trough concentrations (in-house-developed ELISA) and antibodies to infliximab (HMSA, Prometheus Laboratories Inc., San Diego, CA). Primary non-response was defined as the absence of clinical improvement at week 14.. The incidence of primary non-response to infliximab was 8% (n = 16). IL-8 concentrations at baseline were higher (p = .01) and albumin at week 6 was lower in primary non-responders (p = .01) compared to responders. During induction, IFN-γ and IL-6 concentrations decreased significantly at week 2 and week 6 in responders compared to primary non-responders (p < .05). Serum TNF increased significantly after each infliximab infusion and this increase from week 0 to week 14 was more pronounced in responders (p = .03). Multiple logistic regression identified TNF/CRP ratio at baseline as predictive for primary non-response to infliximab at week 14 (OR 2.8 (95% CI 1.4-5.5; p = .003)).. In this intensively sampled cohort of Crohn's disease patients, we demonstrate that inflammatory burden is more determining for primary non-response than drug exposure or immunogenicity. Our findings furthermore suggest that the contribution of TNF in inflammation might be higher in primary non-response, contradicting the non-TNF-driven concept.

Topics: Adult; Antibodies; Biomarkers; C-Reactive Protein; Crohn Disease; Cytokines; Female; Gastrointestinal Agents; Humans; Induction Chemotherapy; Infliximab; Interferon-gamma; Interleukin-10; Interleukin-6; Interleukin-8; Male; Middle Aged; Serum Albumin; Treatment Outcome; Tumor Necrosis Factor-alpha

Necroptosis is an inflammatory form of programmed cell death requiring receptor-interacting protein kinase 3 (RIP3) and mixed lineage kinase domain-like protein (MLKL).. The aim of this study is to examine in depth in vitro and ex vivo the contribution of necroptosis to intestinal inflammation.. In vitro: we used an intestinal cell line, HCT116RIP3, produced in our laboratory and overexpressing RIP3. Ex vivo: intestinal mucosal biopsies were taken from patients with inflammatory bowel disease (IBD) (20 with Crohn's disease; 20 with ulcerative colitis) and from 20 controls.. RIP3-induced necroptosis triggers MLKL activation, increases cytokine/alarmin expression (IL-8, IL-1β, IL-33, HMGB1), NF-kBp65 translocation and NALP3 inflammasome assembly. It also affects membrane permeability by altering cell-cell junctional proteins (E-cadherin, Occludin, Zonulin-1). Targeting necroptosis through Necrostatin-1 significantly reduces intestinal inflammation in vitro and in cultured intestinal explants from IBD.. We show for the first time in vitro and ex vivo that RIP3-driven necroptosis seriously affects intestinal inflammation by increasing pMLKL, activating different cytokines and alarmins, and altering epithelial permeability. The inhibition of necroptosis causes a significant decrease of all these effects. These data strongly support the view that targeting necroptosis may represent a promising new option for the treatment of inflammatory enteropathies.

Topics: Adolescent; Amino Acid Chloromethyl Ketones; Apoptosis; Cadherins; Caspase 1; Cell Adhesion; Cell Membrane Permeability; Cell Survival; Child; Child, Preschool; Colitis, Ulcerative; Crohn Disease; Epithelial Cells; HCT116 Cells; HMGB1 Protein; Humans; Imidazoles; Indoles; Inflammasomes; Inflammation; Interleukin-1beta; Interleukin-8; Intestinal Mucosa; Necrosis; NLR Family, Pyrin Domain-Containing 3 Protein; Phosphorylation; Protein Kinases; Protein Transport; Receptor-Interacting Protein Serine-Threonine Kinases; RNA, Messenger; Transcription Factor RelA; Tumor Necrosis Factor-alpha

To investigate interleukin (IL)-26 expression in the inflamed mucosa of patients with inflammatory bowel disease (IBD) and the function of IL-26.. Human colonic subepithelial myofibroblasts (SEMFs) were isolated from colon tissue surgically resected. The expression of IL-26 protein and its receptor complex was analyzed by immunohistochemistry. The gene expression induced by IL-26 was evaluated by real-time polymerase chain reaction. Intracellular signaling pathways were evaluated by immunoblotting and specific small interfering (si) RNA transfection.. These results suggest that IL-26 plays a role in the pathophysiology of IBD through induction of inflammatory mediators.

Topics: Biopsy; Colitis, Ulcerative; Colon; Crohn Disease; Humans; Immunohistochemistry; Interleukin-6; Interleukin-8; Interleukins; Intestinal Mucosa; Mitogen-Activated Protein Kinases; Myofibroblasts; NF-kappa B; Phosphatidylinositol 3-Kinases; Phosphoinositide-3 Kinase Inhibitors; Primary Cell Culture; Real-Time Polymerase Chain Reaction; RNA Interference; RNA, Messenger; RNA, Small Interfering; Signal Transduction; STAT1 Transcription Factor; STAT3 Transcription Factor; Transcription Factor AP-1; Up-Regulation

Exclusive enteral nutrition (EEN) therapy using a polymeric formula (PF) can substantially attenuate intestinal inflammation in Crohn's disease (CD) patients. However, the mechanism(s) by which EEN suppresses inflammation are not yet fully understood. The aims were to examine cellular mechanism(s) through which EEN may suppress inflammation and investigate potential pathways to enhance anti-inflammatory properties of EEN.. Glutamine, arginine, vitamin D. Cellular viability and activity were maintained with all nutrient treatments. Glutamine, arginine, and vitamin D. These data indicate that glutamine, arginine, and vitamin D

Topics: alpha-Linolenic Acid; Anti-Inflammatory Agents; Arginine; Cell Survival; Cholecalciferol; Crohn Disease; Enteral Nutrition; Glutamine; HT29 Cells; Humans; Inflammation; Interleukin-8; NF-kappa B; Nitric Oxide; p38 Mitogen-Activated Protein Kinases; Pharmaceutical Solutions; Phosphorylation; Tumor Necrosis Factor-alpha

Of all B2 phylogroup strains assessed, 79% could survive and replicate in macrophages. Among them, 11/41 strains (5 CD, 2 UCs, 5 non-IBD) also adhere to and invade epithelial cells, a phenotype assigning them to the AIEC pathovar. The AIEC strains were phylogenetically heterogeneous. We did not identify a gene (or nucleic acid base composition differences) common to all, or the majority of, AIEC. Cytokine secretion and CRISPRs were not associated with the AIEC phenotype.. Comparative genomic analysis of AIEC and non-AIEC strains did not identify a molecular property exclusive to the AIEC phenotype. We recommend a broader approach to the identification of the bacteria-host interactions that are important in the pathogenesis of Crohn's disease.

Topics: Bacterial Adhesion; Cell Line; Clustered Regularly Interspaced Short Palindromic Repeats; Crohn Disease; Cytokines; DNA, Bacterial; Epithelial Cells; Escherichia coli; Escherichia coli Infections; Genome; Host-Pathogen Interactions; Humans; Interleukin-10; Interleukin-6; Interleukin-8; Macrophages; Phenotype; Phylogeny; Sequence Analysis, DNA; Tumor Necrosis Factor-alpha

Intestinal subepithelial myofibroblasts (SEMFs) exert a profibrotic role in Crohn's disease (CD). Tumor necrosis factor-like cytokine 1A (TL1A) and its receptors, death-domain receptor 3 (DR3) and decoy receptor 3 (DcR3), are mucosal factors with significant involvement in experimental inflammation and CD. We aimed to determine the regulation of expression of this system of proteins in SEMFs and intestinal epithelial cells. The relative amount of mRNA transcripts for TL1A, DR3, and DcR3 was measured by real-time reverse transcription polymerase chain reaction in cultured primary SEMFs, colonic myofibroblast cell line 18CO, and epithelial cell line HT29. Protein expression was determined by immunofluorescence. The effect of various proinflammatory stimuli in mRNA and protein expression was studied. TL1A mRNA and protein expression in primary SEMFs (and 18CO cells) was significantly upregulated after stimulation with interleukin 1-alpha and/or tumor necrosis factor alpha (TNF-α) (32- to 44-fold increase, P < 0.05 vs unstimulated). Following stimulation with interleukin 1-alpha + TNF-α + IFN-γ, HT-29 cells highly expressed DR3 (4.1-fold over unstimulated, P = 0.008) and DcR3 (56-fold, P = 0.009) and secreted soluble factors that led to induction of TL1A mRNA in primary SEMFs (28-fold, P = 0.008). Activated epithelial cells significantly upregulated IL-8 expression in response to stimulation with recombinant TL1A. Supernatants from mucosal cultures of patients with CD were able to stimulate the expression of TL1A in cultured primary SEMFs, in comparison to supernatants from healthy controls (3.8-fold increase, P < 0.05) or culture media alone (P < 0.05). In conclusion, we found that proinflammatory cytokines are important regulators of the expression of TL1A in SEMFs and of its receptors in intestinal epithelial cells. Our results raise the possibility for involvement of TL1A/DR3/DR3-mediated mechanisms in epithelial-mesenchymal interactions and the development of inflammation-induced intestinal fibrosis in CD.

Topics: Crohn Disease; Epithelial Cells; HT29 Cells; Humans; Inflammation Mediators; Interleukin-8; Intestinal Mucosa; Myofibroblasts; Receptors, Tumor Necrosis Factor, Member 25; Receptors, Tumor Necrosis Factor, Member 6b; RNA, Messenger; Solubility; Tumor Necrosis Factor Ligand Superfamily Member 15

The miR-29 family is involved in fibrosis in multiple organs, including the intestine where miR-29b facilitates TGF-β-mediated up-regulation of collagen in mucosal fibroblasts from Crohn's disease (CD) patients. Myeloid cell leukemia-1 (MCL-1), a member of the B-cell CLL/Lymphoma 2 (BCL-2) apoptosis family, is involved in liver fibrosis and is targeted by miR-29b via its 3'-UTR in cultured cell lines. We investigate the role of MCL-1 and miR-29b in primary intestinal fibroblasts and tissue from stricturing CD patients. Transfection of CD intestinal fibroblasts with pre-miR-29b resulted in a significant increase in the mRNA expression of MCL-1 isoforms [MCL-1Long (L)/Extra Short (ES) and MCL-1Short (S)], although MCL-1S was expressed at significantly lower levels. Western blotting predominantly detected the anti-apoptotic MCL-1L isoform, and immunofluorescence showed that staining was localised in discrete nuclear foci. Transfection with pre-miR-29b or anti-miR-29b resulted in a significant increase or decrease, respectively, in MCL-1L foci. CD fibroblasts treated with IL-6 and IL-8, inflammatory cytokines upstream of MCL-1, increased the total mass of MCL-1L-positive foci. Furthermore, transfection of intestinal fibroblasts with pre-miR-29b resulted in an increase in mRNA and protein levels of IL-6 and IL-8. Finally, immunohistochemistry showed reduced MCL-1 protein expression in fibrotic CD samples compared to non-stricturing controls. Together, our findings suggest that induction of MCL-1 by IL-6/IL-8 may surmount any direct down-regulation by miR-29b via its 3'-UTR. We propose that an anti-fibrotic miR-29b/IL-6 IL-8/MCL-1L axis may influence intestinal fibrosis in CD. In the future, therapeutic modulation of this pathway might contribute to the management of fibrosis in CD.

Topics: 3' Untranslated Regions; Base Sequence; Binding Sites; Crohn Disease; Fibroblasts; Fibrosis; Humans; Interleukin-6; Interleukin-8; Intestines; MicroRNAs; Models, Biological; Myeloid Cell Leukemia Sequence 1 Protein; Protein Isoforms; RNA, Messenger; Transfection; Up-Regulation

Human cystatin C, a member of the cysteine proteinase-inhibitory family, is produced by all nucleated cells and has important roles in regulating natural immunity. Nematode homologs to human cystatin C have been shown to have anti-inflammatory effects on monocytes and to reduce colitis in mice. In Crohn's disease, pathogenic activated monocytes help drive inflammatory processes via the release of proinflammatory cytokines and chemokines. In particular, tumor necrosis factor-α-producing inflammatory monocytes have a central role in the intestinal inflammation in patients with Crohn's disease. We investigated the potential of human cystatin C to regulate pathogenic activated monocytes and its potential as an Immunomodulator in Crohn's disease. We found that cystatin C significantly decreased the lipopolysaccharide-stimulated release and expression of interleukin-1β and tumor necrosis factor-α in monocyte and peripheral blood mononuclear cell cultures from healthy donors, whereas interleukin-6 and interleukin-8 levels were unchanged. A similar reduction of interleukin-1β and tumor necrosis factor-α was also seen in peripheral blood mononuclear cell cultures from patients with Crohn's disease, and in particular, tumor necrosis factor-α was reduced in supernatants from lamina propria cell cultures from patients with Crohn's disease. Further investigation revealed that cystatin C was internalized by monocytes via an active endocytic process, decreased phosphorylation of the mitogen-activated protein kinase pathway extracellular signal-regulated kinase-1/2, and altered surface marker expression. The ability of cystatin C to modulate the cytokine expression of monocytes, together with its protease-inhibitory function, indicates that modulation of the local cystatin C expression could be an option in future Crohn's disease therapy.

Topics: Antigens, Surface; Carbocyanines; Caspase 1; Cells, Cultured; Crohn Disease; Cystatin C; Gene Expression Regulation; Humans; Interleukin-1beta; Interleukin-6; Interleukin-8; Lipopolysaccharides; MAP Kinase Signaling System; Monocytes; Phosphorylation; Protein Processing, Post-Translational; Recombinant Proteins; Tumor Necrosis Factor-alpha

Triggering receptor expressed on myeloid cells 1 (TREM-1) is a potent amplifier of inflammation. Recently, the antimicrobial peptide PGLYRP-1 was shown to be the ligand of TREM-1. Here, the ability of an anti-TREM-1 antibody to dampen the release of proinflammatory cytokines by colon lamina propria cells (LPCs) from patients with IBD was investigated and correlated with PGLYRP-1 levels.. Biopsies from patients with ulcerative colitis (UC, n = 45) or Crohn's disease (CD, n = 26) were compared with those from individuals undergoing colonoscopy for other reasons (n = 17). TREM-1 expression was analyzed on myeloid cells by flow cytometry. Cell culture experiments with LPCs were used to analyze PGLYRP-1 and inflammatory cytokine levels and assess the effect of anti-TREM-1 on cytokine secretion.. The frequency of TREM-1-expressing neutrophils and recruited macrophages was higher in inflamed than in noninflamed biopsies. The PGLYRP-1 level in inflamed tissue was higher than in noninflamed tissue; it was produced primarily by neutrophils, and its level correlated with the secretion of proinflammatory cytokines. Secretion of myeloperoxidase, tumor necrosis factor-α, interleukin-1β, and interleukin-8 by LPCs stimulated with the potent TREM-1 agonist consisting of PGLYRP-1 complexed with peptidoglycan was reduced in the presence of anti-TREM-1. Moreover, a blocking effect of anti-TREM-1 was apparent when LPCs from a subset of inflamed individuals with elevated PGLYRP-1 were stimulated with killed bacteria.. An anti-TREM-1 antibody can dampen secretion of proinflammatory cytokines in inflamed patients with elevated PGLYRP-1. Moreover, PGLYRP-1 + myeloperoxidase is a potential biomarker for predicting the effect of anti-TREM-1 therapy.

Topics: Adult; Aged; Antibodies; Biomarkers; Case-Control Studies; Cells, Cultured; Colitis, Ulcerative; Crohn Disease; Cytokines; Female; Humans; Interleukin-1beta; Interleukin-8; Intestinal Mucosa; Macrophages; Male; Middle Aged; Neutrophils; Peptidoglycan; Peroxidase; Triggering Receptor Expressed on Myeloid Cells-1; Tumor Necrosis Factor-alpha; Young Adult

Ileal lesions of Crohn's disease [CD] patients are colonised by adherent-invasive Escherichia coli [AIEC] able to survive in macrophage cell lines. We analysed the ability of monocyte-derived macrophages [MDM] from CD patients to control AIEC intracellular replication and the pro-inflammatory cytokine response of the infected-MDM.. Peripheral blood MDM were obtained from 24 CD genotyped for NOD2 and ATG16L1 mutations, 5 ulcerative colitis [UC] patients and 12 healthy controls [HC]. The numbers of intracellular bacteria were determined using gentamicin assay. Cytokine secretion was quantified by ELISA assay.. We observed that higher levels of bacteria were internalised within MDM from CD patients than MDM from HC or UC patients. MDM from CD patients were unable to restrict AIEC intracellular replication. Infection of MDM from CD patients with AIEC resulted in significantly increased secretion of IL-6 and tumour necrosis factor alpha [TNF α] than did infection with non-pathogenic E. coli. AIEC-infected MDM from CD patients exhibited a disordered cytokines secretion compared with MDM from UC patients and HC. AIEC-infected MDM from patients with quiescent CD released significantly higher amounts of IL-6 and TNF-alpha than those with active disease or those from HC. The level of secreted TNF-alpha was correlated to the number of intracellular AIEC in MDM from CD patients. Treatment of MDM with infliximab did not change the MDM behaviour.. MDM from CD patients are unable to restrict intracellular AIEC replication, leading to disordered inflammatory response influenced by disease activity.

Topics: Adult; Anti-Inflammatory Agents, Non-Steroidal; Autophagy-Related Proteins; Bacterial Adhesion; Bacterial Load; Carrier Proteins; Cells, Cultured; Colitis, Ulcerative; Crohn Disease; Escherichia coli; Escherichia coli Infections; Female; Genotype; Humans; Infliximab; Interleukin-6; Interleukin-8; Macrophages; Male; Middle Aged; Nod2 Signaling Adaptor Protein; Polymorphism, Single Nucleotide; Tumor Necrosis Factor-alpha

Inflammatory bowel diseases (IBD), including Crohn's disease (CD) and ulcerative colitis (UC), are characterized by chronic intestinal inflammation due to immunological, microbial, and environmental factors in genetically predisposed individuals. Advances in the diagnosis, prognosis, and treatment of IBD require the identification of robust biomarkers that can be used for molecular classification of diverse disease presentations. We previously identified five genes, RELA, TNFAIP3 (A20), PIGR, TNF, and IL8, whose mRNA levels in colonic mucosal biopsies could be used in a multivariate analysis to classify patients with CD based on disease behavior and responses to therapy.. We compared expression of these five biomarkers in IBD patients classified as having CD or UC, and in healthy controls.. Patients with CD were characterized as having decreased median expression of TNFAIP3, PIGR, and TNF in non-inflamed colonic mucosa as compared to healthy controls. By contrast, UC patients exhibited decreased expression of PIGR and elevated expression of IL8 in colonic mucosa compared to healthy controls. A multivariate analysis combining mRNA levels for all five genes resulted in segregation of individuals based on disease presentation (CD vs. UC) as well as severity, i.e., patients in remission versus those with acute colitis at the time of biopsy.. We propose that this approach could be used as a model for molecular classification of IBD patients, which could further be enhanced by the inclusion of additional genes that are identified by functional studies, global gene expression analyses, and genome-wide association studies.

Topics: Adolescent; Adult; Aged; Chi-Square Distribution; Colitis, Ulcerative; Crohn Disease; DNA-Binding Proteins; Female; Gene Expression; Genetic Markers; Humans; Interleukin-8; Intestinal Mucosa; Intracellular Signaling Peptides and Proteins; Male; Middle Aged; Multivariate Analysis; Nuclear Proteins; Phenotype; Receptors, Polymeric Immunoglobulin; RNA, Messenger; Transcription Factor RelA; Tumor Necrosis Factor alpha-Induced Protein 3; Tumor Necrosis Factor-alpha; Young Adult

The objective of the study is to explore change and significance of IL-8, IL-4 and IL-10 in the pathogenesis of terminal Ileitis in SD rat. 60 male SD rats were divided into model group, suture group, and control group equally. The rats subjected to ileum-cecum side-to-side anastomosis in terminal ileum in model group, suture in terminal ileum in suture group, and the control group accepted no special treatment. The terminal ileum tissue which was 1-3 cm from anastomotic stoma was collected at 2 and 8 weeks after surgery in each group. The pathological slice was observed under microscope, and PCR was applied to detect the expression of IL-4, IL-8, and IL-10 at different times. Pathological result showed that neutrophils significantly increased in model group and suture group at 2nd week, showing acute inflammatory reaction; model group showed chronic inflammation at 8th week. The change of IL-8, IL-4, and IL-10 expression level at 2 weeks after surgery: The IL-8 expression level of SD rat terminal ileum tissue in model group was significantly higher than in control and suture groups (P < 0.01), and it was higher in suture group compared to control group (P < 0.01); the expression level of IL-4 in control group was higher than model and suture groups (P < 0.05); there was no statistical significance between model group and suture group (P = 0.363); the expression level of IL-10 in control group was higher than in model and suture groups (P < 0.01), and it was higher in suture group compared to model group (P < 0.01). The change of IL-8, IL-4, IL-10 expression level at 8 weeks after surgery: The expression level of IL-8 significantly decreased in model group, and there was no significantly difference between three groups (P > 0.05); the expression level of IL-4 was higher in model group and suture group compared to 2nd week; there was no significance between three groups (P < 0.05); the expression of IL-10 was higher in model group compared to 2nd week (P < 0.01), it was lower than control group and suture group (P < 0.01); there was no significant difference between suture group and control group (P > 0.05). The chronic terminal ileum model could be successfully established by ileum-cecum side-to-side anastomosis in terminal ileum in SD rats; IL-8 can induce the inflammatory reaction in terminal ileitis and chemokines aggregation and mediate inflammatory reaction by mediating other inflammatory factors; as a proinflammatory cytokine, IL-8 can inhibit IL-10

Topics: Animals; Crohn Disease; Disease Models, Animal; Ileum; Interleukin-10; Interleukin-4; Interleukin-8; Male; Neutrophils; Rats; Rats, Sprague-Dawley; Sutures; Time Factors

Crohn's disease is a multifactorial disease in which an aberrant immune response to commensal intestinal microbiota leads to chronic inflammation. The small intestine of patients with Crohn's disease is colonized by a group of adherent-invasive Escherichia coli strongly able to adhere and invade intestinal epithelial cells lactoferrin is an iron-binding glycoprotein known to have anti-bacterial and anti-inflammatory activities.. We explore the ability of bovine lactoferrin to modulate the interactions between the adherent-invasive E. coli strain LF82 and intestinal epithelial cells as well as the inflammatory response.. Bacterial adhesion and invasion assays were used to assess the antimicrobial activity of lactoferrin. Electron microscopy was used to characterize bacteria-cell interactions. The mRNA expression of pro-inflammatory cytokines was measured both in cultured cells and in biopsies taken from intestine of patients affected by Crohn's disease.. Lactoferrin inhibited bacterial invasion through minimally affecting adhesion. This divergence was due to a mannose-dependent lactoferrin binding to the bacterial type 1 pili and consequent bacterial aggregation on the intestinal epithelial cell surface. Expression of pro-inflammatory cytokines, such as TNF-alpha, IL-8, and IL-6, was markedly inhibited by lactoferrin both in cultured and Crohn-derived intestinal cells.. Bovine lactoferrin might function via an antibacterial and/or anti-inflammatory mechanism in the treatment of Crohn's disease.

Topics: Animals; Anti-Infective Agents; Bacterial Adhesion; Caco-2 Cells; Cattle; Crohn Disease; Escherichia coli; Escherichia coli Infections; Gene Expression; Humans; Interferon-gamma; Interleukin-6; Interleukin-8; Intestinal Mucosa; Lactoferrin; Mannose; Microscopy, Electron, Scanning; Microscopy, Electron, Transmission; Receptors, Immunologic; RNA, Messenger; Tumor Necrosis Factor-alpha

Mast cells are now considered sentinels in immunity. Given their location underneath the gastrointestinal barrier, mast cells are entrusted with the task of tolerating commensal microorganisms and eliminating potential pathogens in the gut microbiota. The aim of our study was to analyse the responsiveness of mast cells isolated from macroscopically normal and Crohn's disease-affected intestine to lipopolysaccharide (LPS). To determine the LPS-mediated signalling, human intestinal mast cells were treated with LPS alone or in combination with soluble CD14 due to their lack of surface CD14 expression. LPS alone failed to stimulate cytokine expression in human intestinal mast cells from both macroscopically normal and Crohn's disease tissue. Upon administration of LPS and soluble CD14, there was a dose- and time-dependent induction of cytokine and chemokine expression. Moreover, CXCL8 and interleukin-1β protein expression was induced in response to activation with LPS plus soluble CD14. Expression of cytokines and chemokines was at similar levels in mast cells from macroscopically normal and Crohn's disease-affected intestine after LPS/soluble CD14 treatment. In conclusion, human intestinal mast cells appear to tolerate LPS per se. The LPS-mediated activation in mast cells may be provoked by soluble CD14 distributed by other LPS-triggered cells at the gastrointestinal barrier.

Topics: Cells, Cultured; Crohn Disease; Dose-Response Relationship, Drug; Humans; Interleukin-1beta; Interleukin-8; Intestinal Mucosa; Intestines; Lipopolysaccharide Receptors; Lipopolysaccharides; Mast Cells; RNA, Messenger; Time Factors; Toll-Like Receptor 4

Giardia duodenalis (syn. G. intestinalis, G. lamblia) infections are a leading cause of waterborne diarrheal disease that can also result in the development of postinfectious functional gastrointestinal disorders via mechanisms that remain unclear. Parasite numbers exceed 10(6) trophozoites per centimeter of gut at the height of an infection. Yet the intestinal mucosa of G. duodenalis-infected individuals is devoid of signs of overt inflammation. G. duodenalis infections can also occur concurrently with infections with other proinflammatory gastrointestinal pathogens. Little is known of whether and how this parasite can attenuate host inflammatory responses induced by other proinflammatory stimuli, such as a gastrointestinal pathogen. Identifying hitherto-unrecognized parasitic immunomodulatory pathways, the present studies demonstrated that G. duodenalis trophozoites attenuate secretion of the potent neutrophil chemoattractant interleukin-8 (CXCL8); these effects were observed in human small intestinal mucosal tissues and from intestinal epithelial monolayers, activated through administration of proinflammatory interleukin-1β or Salmonella enterica serovar Typhimurium. This attenuation is caused by the secretion of G. duodenalis cathepsin B cysteine proteases that degrade CXCL8 posttranscriptionally. Furthermore, the degradation of CXCL8 via G. duodenalis cathepsin B cysteine proteases attenuates CXCL8-induced chemotaxis of human neutrophils. Taken together, these data demonstrate for the first time that G. duodenalis trophozoite cathepsins are capable of attenuating a component of their host's proinflammatory response induced by a separate proinflammatory stimulus.

Topics: Cells, Cultured; Chemotaxis; Crohn Disease; Giardia lamblia; Humans; Interleukin-8; Intestinal Mucosa; Neutrophils; Peptide Hydrolases; Salmonella typhimurium

NOD2 encodes an intracellular multidomain pattern recognition receptor that is the strongest known genetic risk factor in the pathogenesis of Crohn disease (CD), a chronic relapsing inflammatory disorder of the intestinal tract. NOD2 functions as a sensor for bacterial cell wall components and activates proinflammatory and antimicrobial signaling pathways. Here, using a genome-wide small interfering RNA (siRNA) screen, we identify numerous genes that regulate secretion of the proinflammatory cytokine IL-8 in response to NOD2 activation. Moreover, many of the identified IL-8 regulators are linked by protein-protein interactions, revealing subnetworks of highly connected IL-8 regulators implicated in processes such as vesicle formation, mRNA stability, and protein ubiquitination and trafficking. A TNFα counterscreen to induce IL-8 secretion in an NOD2-independent manner reveals that the majority of the identified regulators affect IL-8 secretion irrespective of the initiating stimuli. Using immortalized macrophages, we validate the ubiquitin protease, USP8, and the endosomal sorting protein, VPS28, as negative regulators of NOD2-induced cytokine secretion. Interestingly, several genes that affect NOD2-induced IL-8 secretion are present in loci associated with CD risk by genome-wide association studies, supporting a role for the NOD2/IL-8 pathway, and not just NOD2, in the pathogenesis of CD. Overall, this screen provides a valuable resource in the advancement of our understanding of the genes that regulate the secretion of IL-8.

Topics: Animals; Bone Marrow Cells; Cell Line, Transformed; Crohn Disease; Endopeptidases; Endosomal Sorting Complexes Required for Transport; Genetic Loci; Genome-Wide Association Study; HEK293 Cells; High-Throughput Screening Assays; Humans; Interleukin-8; Macrophages; Mice; NF-kappa B; Nod2 Signaling Adaptor Protein; Protein Interaction Mapping; Protein Transport; RNA Stability; RNA, Small Interfering; Tumor Necrosis Factor-alpha; Ubiquitin Thiolesterase; Ubiquitination

The role of the innate immunity in the pathogenesis of Crohn's disease (CD), an inflammatory bowel disease, is a subject of increasing interest. Neutrophils (PMN) are key members of the innate immune system which migrate to sites of bacterial infection and initiate the defence against microbes by producing reactive oxygen species (ROS), before undergoing apoptosis. It is believed that impaired innate immune responses contribute to CD, but it is as yet unclear whether intrinsic defects in PMN signal transduction and corresponding function are present in patients with quiescent disease. We isolated peripheral blood PMN from CD patients in remission and healthy controls (HC), and characterised migration, bacterial uptake and killing, ROS production and cell death signalling. Whereas IL8-induced migration and signalling were normal in CD, trans-epithelial migration was significantly impaired. Uptake and killing of E. coli were normal. However, an increased ROS production was observed in CD PMN after stimulation with the bacterial peptide analogue fMLP, which was mirrored by an increased fMLP-triggered ERK and AKT signal activation. Interestingly, cleavage of caspase-3 and caspase-8 during GMCSF-induced rescue from cell-death was decreased in CD neutrophils, but a reduced survival signal emanating from STAT3 and AKT pathways was concomitantly observed, resulting in a similar percentage of end stage apoptotic PMN in CD patients and HC. In toto, these data show a disturbed signal transduction activation and functionality in peripheral blood PMN from patients with quiescent CD, which point toward an intrinsic defect in innate immunity in these patients.

Topics: Adult; Aged; Apoptosis; Caspases; Cell Movement; Crohn Disease; Epithelial Cells; Escherichia coli; Extracellular Signal-Regulated MAP Kinases; Female; Granulocyte-Macrophage Colony-Stimulating Factor; Humans; Interleukin-8; Male; Middle Aged; N-Formylmethionine Leucyl-Phenylalanine; Neutrophils; Phosphorylation; Proteolysis; Proto-Oncogene Proteins c-akt; Reactive Oxygen Species; Signal Transduction; STAT3 Transcription Factor; Young Adult

The aim of this study is to understand intracellular regulatory mechanisms in peripheral blood mononuclear cells (PBMCs), which are either common to many autoimmune diseases or specific to some of them. We incorporated large-scale data such as protein-protein interactions, gene expression and demographical information of hundreds of patients and healthy subjects, related to six autoimmune diseases with available large-scale gene expression measurements: multiple sclerosis (MS), systemic lupus erythematosus (SLE), juvenile rheumatoid arthritis (JRA), Crohn's disease (CD), ulcerative colitis (UC) and type 1 diabetes (T1D). These data were analyzed concurrently by statistical and systems biology approaches tailored for this purpose. We found that chemokines such as CXCL1-3, 5, 6 and the interleukin (IL) IL8 tend to be differentially expressed in PBMCs of patients with the analyzed autoimmune diseases. In addition, the anti-apoptotic gene BCL3, interferon-γ (IFNG), and the vitamin D receptor (VDR) gene physically interact with significantly many genes that tend to be differentially expressed in PBMCs of patients with the analyzed autoimmune diseases. In general, similar cellular processes tend to be differentially expressed in PBMC in the analyzed autoimmune diseases. Specifically, the cellular processes related to cell proliferation (for example, epidermal growth factor, platelet-derived growth factor, nuclear factor-κB, Wnt/β-catenin signaling, stress-activated protein kinase c-Jun NH2-terminal kinase), inflammatory response (for example, interleukins IL2 and IL6, the cytokine granulocyte-macrophage colony-stimulating factor and the B-cell receptor), general signaling cascades (for example, mitogen-activated protein kinase, extracellular signal-regulated kinase, p38 and TRK) and apoptosis are activated in most of the analyzed autoimmune diseases. However, our results suggest that in each of the analyzed diseases, apoptosis and chemotaxis are activated via different subsignaling pathways. Analyses of the expression levels of dozens of genes and the protein-protein interactions among them demonstrated that CD and UC have relatively similar gene expression signatures, whereas the gene expression signatures of T1D and JRA relatively differ from the signatures of the other autoimmune diseases. These diseases are the only ones activated via the Fcɛ pathway. The relevant genes and pathways reported in this study are discussed at length, and may be helpful in the d

Topics: Apoptosis; Arthritis, Juvenile; Autoimmune Diseases; B-Cell Lymphoma 3 Protein; Cell Proliferation; Chemokine CXCL1; Chemokine CXCL5; Chemokine CXCL6; Chemokines, CXC; Colitis, Ulcerative; Crohn Disease; Diabetes Mellitus, Type 1; Gene Expression; Humans; Inflammation; Interferon-gamma; Interleukin-8; Leukocytes, Mononuclear; Lupus Erythematosus, Systemic; MAP Kinase Signaling System; Mitogen-Activated Protein Kinases; Multiple Sclerosis; Protein Interaction Maps; Proto-Oncogene Proteins; Receptors, Calcitriol; Receptors, IgE; Signal Transduction; Transcription Factors; Transcriptome

Crohn's disease (CD) and ulcerative colitis (UC), known as inflammatory bowel diseases (IBD), are characterized by an abnormal immunological response to commensal bacteria colonizing intestinal lumen and mucosa. Among the latter, strains of adherent-invasive Escherichia coli (AIEC), capable of adhering to and invading epithelium, and to replicate in macrophages, have been described in CD adults. We aimed at identifying and characterizing AIEC strains in pediatric IBD.. In all, 24 CD children, 10 UC, and 23 controls were investigated. Mucosal biopsies, taken during colonoscopy, were analyzed for the presence of AIEC strains by an adhesive-invasive test. Protein expression of the specific AIEC receptor, the carcinoembryonic antigen-related cell adhesion molecule 6 (CEACAM6), was evaluated by western blot and immunohistochemistry, while tumor necrosis factor alpha (TNF-α) and interleukin (IL)-8 mRNA expression was detected by real-time polymerase chain reaction (PCR), after bacterial infection. Transmission electron microscopy and trans-epithelial electric resistance assays were performed on biopsies to assess bacteria-induced morphological and functional epithelial alterations.. Two bacterial strains, EC15 and EC10, were found to adhere and invade the Caco2 cell line, similar to the well-known AIEC strain LF82 (positive control): they upregulated CEACAM6, TNF-α, and IL-8 gene/protein expression, in vitro and in cultured intestinal mucosa; they could also survive inside macrophages and damage the epithelial barrier integrity. Lesions in the inflamed tissues were associated with bacterial infection.. This is the first study showing the presence of adhesive-invasive bacteria strains in the inflamed tissues of children with IBD. Collective features of these strains indicate that they belong to the AIEC spectrum, suggesting their possible role in disease pathogenesis.

Topics: Adolescent; Animals; Antigens, CD; Bacterial Adhesion; Blotting, Western; Case-Control Studies; Cell Adhesion Molecules; Cells, Cultured; Child; Colitis, Ulcerative; Crohn Disease; Escherichia coli; Escherichia coli Infections; Female; Fluorescent Antibody Technique; GPI-Linked Proteins; Humans; Immunoenzyme Techniques; Interleukin-8; Intestinal Mucosa; Macrophages; Male; Mice; Organ Culture Techniques; Real-Time Polymerase Chain Reaction; RNA, Messenger; Tumor Necrosis Factor-alpha

Genotypic variation in signal transducer and activator of transcription 3 (STAT3) increases risk for inflammatory bowel disease (IBD), and STAT3-dependent inflammatory networks are induced in the colon in these patients. We hypothesized that STAT3 "A" risk allele carriage would be associated with increased cellular STAT3 activation and colon leukocyte recruitment.. Colonic expression of genes regulating STAT3 signaling and leukocyte recruitment and function was measured in pediatric patients with Crohn disease (CD) stratified by STAT3 genotype. The frequency of colonic pSTAT3* and CXCR2* neutrophils was determined using immunohistochemistry. STAT3 tyrosine phosphorylation (pSTAT3) was measured in circulating leukocytes by flow cytometry, and mechanisms regulating STAT3 activation were tested in IBD Epstein-Barr virus (EBV)-transformed lymphocytes (EBL).. Colonic expression of interleukin 6 (IL-6), the STAT3 target gene SOCS3, the neutrophil chemoattractants IL-8, CXCL1, and CXCL3, and the neutrophil products S100A8, S100A9, and S100A12 were increased in patients carrying the STAT3 "A" risk allele. The frequency of neutrophils expressing the cognate receptor for IL-8, CXCR2, was increased in colonic biopsies from patients carrying the risk allele, and the frequency of pSTAT3* or CXCR2* neutrophils correlated with histologic severity. The frequency of CD4 lymphocytes and granulocytes expressing pSTAT3 was increased in patients carrying the STAT3 "A" risk allele. EBLs from patients carrying the STAT3 "A" risk allele exhibited increased basal and IL-6-stimulated STAT3 tyrosine phosphorylation, increased transcription of STAT3 and SOCS3 after IL-6 stimulation, and increased membrane localization of the IL-6 receptor, GP130, and Janus-associated kinase 2.. The STAT3 "A" risk allele is associated with increased cellular STAT3 activation and upregulation of pathways that promote recruitment of CXCR2* neutrophils to the gut.

Topics: Adolescent; Alleles; B-Lymphocytes; Calgranulin A; Calgranulin B; CD4-Positive T-Lymphocytes; Cells, Cultured; Chemokine CXCL1; Chemokines, CXC; Child; Colon; Crohn Disease; Female; Gene Expression; Genetic Variation; Genotype; Humans; Interleukin-1; Interleukin-6; Interleukin-8; Janus Kinase 2; Lymphocyte Count; Male; Neutrophils; Phosphorylation; Polymorphism, Single Nucleotide; Receptors, Interleukin-8B; S100 Proteins; S100A12 Protein; Signal Transduction; STAT3 Transcription Factor; Suppressor of Cytokine Signaling 3 Protein; Suppressor of Cytokine Signaling Proteins; Tyrosine; Up-Regulation

To reveal specific gene activation in nitric oxide (NO)-related inflammation we studied differential gene expression in inflammatory bowel disease (IBD).. Total RNA was isolated from 20 biopsies of inflamed mucosa from Crohn's disease (CD) and ulcerative colitis (UC) patients each as well as from six controls, labeled with (32)P-dCTP and hybridized to a human NO gene array. Significant genes were analyzed for functional gene interactions and heatmaps generated by hierarchical clustering. A selection of differentially expressed genes was further evaluated with immunohistochemical staining.. Significant gene expression differences were found for 19 genes in CD and 23 genes in UC compared to controls, both diseases with high expression of ICAM1 and IL-8. Correlation between microarray expression and corresponding protein expression was significant (r = 0.47, p = 0.002). Clustering analysis together with functional gene interaction analysis revealed clusters of coregulation and coexpression in CD and UC: transcripts involved in angiogenesis, inflammatory response mediated by the transcription factor hypoxia-inducible factor 1, and tissue fibrosis. Also, a fourth cluster with transcripts regulated by the transcription factor Sp1 was found in UC.. Expression analysis in CD and UC revealed disease-specific regulation of NO-related genes, which might be involved in perpetuating inflammatory disease activity in IBD.

Topics: Adolescent; Adult; Aged; Aged, 80 and over; Case-Control Studies; Chi-Square Distribution; Cluster Analysis; Colitis, Ulcerative; Crohn Disease; Female; Fibrosis; Gene Expression; Gene Expression Profiling; Humans; Hypoxia-Inducible Factor 1; Intercellular Adhesion Molecule-1; Interleukin-1beta; Interleukin-8; Male; Matrix Metalloproteinase 1; Middle Aged; Neovascularization, Pathologic; NF-kappa B; Nitric Oxide; Nitric Oxide Synthase Type II; Oligonucleotide Array Sequence Analysis; Signal Transduction; Sp1 Transcription Factor; Statistics, Nonparametric; Young Adult

Human ex vivo evidence indicating that an inappropriate immune response(s) to nonpathogenic bacteria contributes to disease pathogenesis in pediatric Crohn's disease (CD) is limited. The aim of the present study was to compare and contrast the early innate immune response of pediatric "healthy" versus CD mucosa to pathogenic, probiotic, and commensal bacteria.. "Healthy control" and CD pediatric mucosal biopsies (terminal ileum and transverse colon) were cocultured for 8 hours with E. coli O42, Lactobacillus GG (LGG), Bacteroidesthetaiotaomicron (B. theta), or stimulated with interleukin (IL)-1β (positive control). Matched nonstimulated biopsies served as experimental controls. IL-8 was the immune marker of choice. IL-8 mRNA and protein levels were quantified by quantitative polymerase chain reaction and sandwich enzyme-linked immunosorbent assay, respectively.. IL-8 secretion was observed when control, ileal biopsies were exposed to pathogenic O42 and probiotic LGG, with no response noted to commensal B. theta. In comparison, Crohn's ileal biopsies showed impaired ability to induce IL-8 in response to O42 and LGG. Control colonic tissue showed a limited response to O42 or B. theta and LGG significantly reduced IL-8 secretion. Unlike control tissue, however, Crohn's ileal and colonic tissue did respond to B. theta, with more enhanced expression in the colon.. We provide the first ex vivo data to support the notion that aberrant mucosal recognition of commensal bacteria may contribute to pediatric CD. While IL-8 responses to O42 and LGG varied with disease status and anatomical location, B. theta consistently induced significant IL-8 both in ileal and colonic CD tissue, which was not seen in control, healthy tissue.

Topics: Bacteroides; Biopsy; Child; Colon; Crohn Disease; Gene Expression; Humans; Interleukin-1beta; Interleukin-8; Intestinal Mucosa; Metagenome; Organ Culture Techniques; Probiotics

The macrophage plays a major role in the induction and resolution phases of inflammation; however, how lipid mediator-derived signals may modulate macrophage function in the resolution of inflammation driven by microbes (e.g., in inflammatory bowel disease) is not well understood. We examined the effects of aspirin-triggered lipoxin (ATL), a stable analog of lipoxin A(4), on the antimicrobial responses of human peripheral blood mononuclear cell-derived macrophages and the monocytic THP-1 cell line. Additionally, we assessed the expression and localization of the lipoxin receptor, formyl peptide receptor 2 (FPR2), in colonic mucosal biopsies from patients with Crohn's disease to determine whether the capacity for lipoxin signaling is altered in inflammatory bowel disease. We found that THP-1 cells treated with ATL (100 nM) displayed increased phagocytosis of inert fluorescent beads and Escherichia coli in a scavenger receptor- and PI3K-dependent, opsonization-independent manner. This ATL-induced increase in phagocytosis was also observed in primary human macrophages, where it was associated with an inhibition of E. coli-induced IL-1β and IL-8 production. Finally, we found that FPR2 gene expression was increased approximately sixfold in the colon of patients with Crohn's disease, a finding reproduced in vitro by the treatment of THP-1 cells with interferon-γ or lipopolysaccharide. These results suggest that lipoxin signaling is upregulated in inflammatory environments, and, in addition to their known role in tissue resolution following injury, lipoxins can enhance macrophage clearance of invading microbes.

Topics: Aspirin; Class Ib Phosphatidylinositol 3-Kinase; Crohn Disease; Humans; Interleukin-1beta; Interleukin-8; Leukocytes, Mononuclear; Lipoxins; Macrophages; Phagocytosis; Receptors, CCR7; Receptors, Formyl Peptide; Receptors, Lipoxin; Up-Regulation

Ileal lesions in Crohn's disease (CD) patients are colonized by pathogenic adherent-invasive Escherichia coli (AIEC) able to adhere to and invade intestinal epithelial cells (IEC), and to survive within macrophages. The interaction of AIEC with IEC depends on bacterial factors mainly type 1 pili, flagella, and outer membrane proteins. In humans, proteases can act as host defence mechanisms to counteract bacterial colonization. The protease meprin, composed of multimeric complexes of the two subunits alpha and beta, is abundantly expressed in IECs. Decreased levels of this protease correlate with the severity of the inflammation in patients with inflammatory bowel disease. The aim of the present study was to analyze the ability of meprin to modulate the interaction of AIEC with IECs. In patients with ileal CD we observed decreased levels of meprins, in particular that of meprin β. Dose-dependent inhibition of the abilities of AIEC strain LF82 to adhere to and invade intestinal epithelial T84 cells was observed when bacteria were pre-treated with both exogenous meprin α and meprin β. Dose-dependent proteolytic degradation of type 1 pili was observed in the presence of active meprins, but not with heat-inactivated meprins, and pretreatment of AIEC bacteria with meprins impaired their ability to bind mannosylated host receptors and led to decreased secretion of the pro-inflammatory cytokine IL-8 by infected T84 cells. Thus, decreased levels of protective meprins as observed in CD patients may contribute to increased AIEC colonization.

Topics: Adult; Aged; Aged, 80 and over; Animals; Bacterial Adhesion; Crohn Disease; Escherichia coli; Female; Humans; Interleukin-8; Intestinal Mucosa; Male; Metalloendopeptidases; Mice; Mice, Inbred C57BL; Middle Aged

Dendritic cell (DC) function is believed to be of critical importance for the pathogenesis of inflammatory bowel disease (IBD). To date, most research in animal models and the few human data available is restricted to myeloid DC, while plasmacytoid DC (pDC) capable of controlling both innate and adaptive immune responses have not yet been investigated systematically in human Crohn's disease (CD) or ulcerative colitis (UC). CD11c(-) , CD303(+) /CD304(+) and CD123(+) pDC from peripheral blood (n = 90), mucosal tissue (n = 28) or mesenteric lymph nodes (n = 40) (MLNs) of patients with UC and CD or controls were purified and cultured. Thereafter, pDC were enumerated, phenotyped and cytokine secretion measured by flow cytometry (FACS), immunohistochemistry and/or cytometric bead array, respectively. Interferon (IFN)-α secretion following cytosine phosphatidyl guanine (CpG) A oligodeoxynucleotide (ODN) 2216 (5'-GGGGGACGATCGTCGGGGGG-3') stimulation was assessed by enzyme-linked immunosorbent assay (ELISA). We found a significantly higher frequency of pDC in the inflamed colonic mucosa and MLN of IBD patients. Moreover, the fraction of CD40 and CD86 expressing cultured peripheral blood pDC was significantly higher in flaring UC and CD patients and their secretion of tumour necrosis factor (TNF)-α, interleukin (IL)-6 and IL-8 were increased significantly compared with controls. In contrast, the IFN-α secretion of peripheral blood pDC isolated from flaring IBD, particularly in UC patients, was reduced significantly compared with controls. Our data suggest an aberrant distribution and function of pDC in IBD, contrary to their generally implicated role as inducers of tolerance. We speculate that the impaired IFN-α secretion may relate to the hypothesized defect in innate immunity in IBD and could also impact upon the generation of regulatory T cells (T(reg) ).

Topics: Adult; Aged; Antigens, CD; Colitis, Ulcerative; Crohn Disease; Dendritic Cells; Enzyme-Linked Immunosorbent Assay; Female; Flow Cytometry; Humans; Immunohistochemistry; Interferon-alpha; Interleukin-6; Interleukin-8; Intestinal Mucosa; Lymph Nodes; Male; Middle Aged; Oligodeoxyribonucleotides; Tumor Necrosis Factor-alpha

High-mobility group box 1 (HMGB1) is a nuclear protein with functions in the regulation of transcription. In inflammatory conditions, HMGB1 is actively secreted from immune cells in the extracellular matrix, where it behaves as a proinflammatory cytokine. The aim of the present study was to investigate the role of HMGB1 in pediatric inflammatory bowel disease (IBD).. We analyzed the stools of 19 children with Crohn's disease (CD), 21 with ulcerative colitis (UC), and 13 controls. The gene/protein expression levels of HMGB1 were assessed in bioptic specimens of all children using real-time PCR and western blot assay. Finally, intracellular localization of the protein was analyzed by western blot, after separation of nuclear and cytoplasmic extracts, and by immunohistochemistry.. HMGB1 protein levels were significantly increased (P<0.001) in the stools of patients, but were undetectable in the controls; fecal HMGB1 correlated well with fecal calprotectin levels (r: 0.77 in CD, r: 0.70 in UC; P<0.01); and mRNA and protein expression were unchanged in inflamed bioptic tissues compared with controls. However, by separately analyzing the nuclear and cytoplasmic fraction, we detected the cytoplasmic HMGB1 expression to be significantly enhanced (P<0.01) in the inflamed tissues of the patients. In addition, HMGB1 was significantly detected in 16 patients with inactive disease, whose endoscopic scores showed persisting inflammation, suggesting that it may be a sensitive marker of mucosal inflammation, although the disease is clinically inactive.. It was shown for the first time in our study that HMGB1 is secreted by human inflamed intestinal tissues and abundantly found in the stools of IBD patients. Hence, it can be considered as a novel marker for intestinal inflammation. We can also suggest that the presence of HMGB1 in large amounts in the fecal stream of IBD patients is mainly due to active secretion of the protein stored in the nucleus rather than a "de novo" synthesis.

Topics: Active Transport, Cell Nucleus; Adolescent; Biomarkers; Biopsy; Caco-2 Cells; Cell Nucleus; Child; Child, Preschool; Colitis, Ulcerative; Crohn Disease; Feces; Female; HMGB1 Protein; Humans; Infant; Interferon-alpha; Interferon-gamma; Interleukin-8; Intestinal Mucosa; Male; RNA, Messenger

Escherichia coli gene fimA was the most frequent gene that occurred in the intestine of all investigated groups. All subjects with fimA gene had significantly higher values of tumor necrosis factor alpha (TNF-α) and CRP than those with other E. coli genes. There was also a tendency to increased serum interleukin (IL)-6 levels in patients carrying the fimA gene; however, no relation was observed to serum IL-8 and IL-10. Patients with Crohn's disease had significantly higher IL-6 than those with ulcerative colitis (UC) and controls. The highest levels of TNF-α were detected in the UC group. There were no significant differences in serum IL-8 and IL-10 between all three groups. The presence of E. coli gene fimA in the large bowel of patients with IBD is related to the immunological activity of the disease which may be important from the aspect of therapeutical strategy.

Topics: Adult; Aged; Anti-Bacterial Agents; Bacterial Typing Techniques; Case-Control Studies; Colitis, Ulcerative; Crohn Disease; Czech Republic; Escherichia coli; Escherichia coli Infections; Female; Fimbriae Proteins; Humans; Inflammation; Interleukin-10; Interleukin-6; Interleukin-8; Intestines; Male; Middle Aged; Polymerase Chain Reaction; Tumor Necrosis Factor-alpha

Saccharomyces boulardii (Sb) is a probiotic yeast that has demonstrated efficacy in pilot studies in patients with inflammatory bowel disease (IBD). Microbial antigen handling by dendritic cells (DC) is believed to be of critical importance for immunity and tolerance in IBD. The aim was to characterize the effects of Sb on DC from IBD patients. Highly purified (>95%), lipopolysaccharide-stimulated CD1c(+)CD11c(+)CD123(-) myeloid DC (mDC) from patients with ulcerative colitis (UC; n = 36), Crohn's disease (CD; n = 26), or infectious controls (IC; n = 4) were cultured in the presence or absence of fungal supernatant from Sb (SbS). Phenotype and cytokine production and/or secretion of IBD mDC were measured by flow cytometry and cytometric bead arrays, respectively. T cell phenotype and proliferation were assessed in a mixed lymphocyte reaction (MLR) with allogenic CD4(+)CD45RA(+) naïve T cells from healthy donors. Mucosal healing was investigated in epithelial wounding and migration assays with IEC-6 cells. SbS significantly decreased the frequency of CD40-, CD80-, and CD197 (CCR7; chemokine receptor-7)-expressing IBD mDC and reduced their secretion of tumor necrosis factor (TNF)-α and interleukin (IL)-6 while increasing IL-8. In the MLR, SbS significantly inhibited T cell proliferation induced by IBD mDC. Moreover, SbS inhibited T(H)1 (TNF-α and interferon-γ) polarization induced by UC mDC and promoted IL-8 and transforming growth factor-β-dependent mucosal healing. In summary, we provide novel evidence of synergistic mechanisms how Sb controls inflammation (inhibition of T cell costimulation and inflammation-associated migration and mobilization of DC) and promotes epithelial restitution relevant in IBD.

Topics: B7-1 Antigen; CD40 Antigens; Cell Division; Cell Movement; Cells, Cultured; Colitis, Ulcerative; Crohn Disease; Dendritic Cells; Female; Humans; Immunotherapy; Interleukin-6; Interleukin-8; Lymphocyte Culture Test, Mixed; Male; Probiotics; Receptors, CCR7; Saccharomyces; T-Lymphocytes; Transforming Growth Factor beta; Tumor Necrosis Factor-alpha

Reduced alpha-defensin expression has been reported in the terminal ileum (TI) of adult patients with ileal Crohn's disease (CD). However, little is known about alpha-defensin expression in children with chronic inflammatory bowel disease (IBD).. In all, 283 intestinal biopsies were obtained from children with CD, ulcerative colitis (UC), and healthy controls. Absolute mRNA copy numbers for HD5, HD6, IL-8, Villin 1, and Tcf-4 were analyzed by reverse-transcription polymerase chain reaction (RT-PCR). HD5 immunostaining was performed on biopsy sections and patients genotyped for NOD2 mutations.. Equal expression levels of alpha-defensins (HD5 and HD6) were found in TI biopsies of children with ileal CD (L1+L3) compared to patients with colonic disease (L2) and healthy controls. In contrast, we found significantly higher levels of alpha-defensins in the TI of children with UC compared to CD and controls. Reduced expression of Tcf-4 was observed exclusively in the duodenum and TI of CD patients with L1+L3 phenotype. We demonstrate significantly increased expression of HD5 and HD6 in the inflamed colon of IBD children (UC and CD) attributable to the presence of metaplastic Paneth cells.. In this study no difference in alpha-defensin expression was found in the TI of CD children and controls. However, significant reduction of Tcf-4 in L1+L3 phenotype suggests that a possibly impaired PC differentiation may lead to altered HD5 and HD6 expression at some stage of disease. Additionally, substantially increased expression of alpha-defensins in the inflamed colonic mucosa of children with IBD raises the question for their potential involvement in modulating inflammation in these patients.

Topics: alpha-Defensins; Basic Helix-Loop-Helix Leucine Zipper Transcription Factors; Case-Control Studies; Child; Colitis, Ulcerative; Colon; Crohn Disease; Female; Fluorescent Antibody Technique; Humans; Ileum; Immunoenzyme Techniques; Interleukin-8; Intestinal Mucosa; Male; Microfilament Proteins; Paneth Cells; Prognosis; Prospective Studies; Real-Time Polymerase Chain Reaction; Reverse Transcriptase Polymerase Chain Reaction; RNA, Messenger; Transcription Factor 4; Transcription Factors

Endoplasmic reticulum (ER) stress has been suggested to play a role in inflammatory bowel disease (IBD). The three branches (ATF6, IRE1 and PERK) of the unfolded protein response (UPR) have different roles and are not necessarily activated simultaneously.. Expression of UPR-related genes was investigated in colonic and ileal biopsies of 23 controls, 15 ulcerative colitis (UC) and 54 Crohn's disease (CD) patients. This expression was confirmed at protein level in colonic and ileal samples of five controls, UC and CD patients. HSPA5, PDIA4 and XBP1s were significantly increased in colonic IBD at mRNA and/or protein levels, indicating activation of the ATF6 and IRE1 branch. Colonic IBD was associated with increased phosphorylation of EIF2A suggesting the activation of the PERK branch, but subsequent induction of GADD34 was not observed. In ileal CD, no differential expression of the UPR-related genes was observed, but our data suggested a higher basal activation of the UPR in the ileal mucosa of controls. This was confirmed by the increased expression of 16 UPR-related genes as 12 of them were significantly more expressed in ileal controls compared to colonic controls. Tunicamycin stimulation of colonic and ileal samples of healthy individuals revealed that although the ileal mucosa is exhibiting this higher basal UPR activation, it is still responsive to ER stress, even more than colonic mucosa.. Activation of the three UPR-related arms is seen in colonic IBD-associated inflammation. However, despite EIF2A activation, inflamed colonic tissue did not increase GADD34 expression, which is usually involved in re-establishment of ER homeostasis. This study also implies the presence of a constitutive UPR activation in healthy ileal mucosa, with no further activation during inflammation. Therefore, engagement of the UPR differs between colon and ileum and this could be a factor in the development of ileal or colonic disease.

Topics: Activating Transcription Factor 6; Adolescent; Adult; Aged; Case-Control Studies; Child; Colitis, Ulcerative; Colon; Crohn Disease; Endoplasmic Reticulum Chaperone BiP; Endoplasmic Reticulum Stress; Endoribonucleases; Endoscopy, Gastrointestinal; Heat-Shock Proteins; Humans; Ileum; Interleukin-8; Intestinal Mucosa; Male; Membrane Proteins; Middle Aged; Protein Serine-Threonine Kinases; RNA, Messenger; Transcriptome; Tunicamycin; Unfolded Protein Response; Young Adult

Interleukin-17A (IL-17A) and IL-17F are 2 of several cytokines produced by T helper 17 cells (Th17), which are able to indirectly induce the recruitment of neutrophils. Recently, human Th17 cells have been phenotypically characterized and shown to express discrete chemokine receptors, including CCR2 and CCR6. Herein, we show that highly purified neutrophils cultured with interferon-gamma plus lipopolysaccharide produce the CCL2 and CCL20 chemokines, the known ligands of CCR2 and CCR6, respectively. Accordingly, supernatants from activated neutrophils induced chemotaxis of Th17 cells, which was greatly suppressed by anti-CCL20 and anti-CCL2 antibodies. We also discovered that activated Th17 cells could directly chemoattract neutrophils via the release of biologically active CXCL8. Consistent with this reciprocal recruitment, neutrophils and Th17 cells were found in gut tissue from Crohn disease and synovial fluid from rheumatoid arthritis patients. Finally, we report that, although human Th17 cells can directly interact with freshly isolated or preactivated neutrophils via granulocyte-macrophage colony-stimulating factor, tumor necrosis factor-alpha, and interferon-gamma release, these latter cells cannot be activated by IL-17A and IL-17F, because of their lack of IL-17RC expression. Collectively, our results reveal a novel chemokine-dependent reciprocal cross-talk between neutrophils and Th17 cells, which may represent a useful target for the treatment of chronic inflammatory diseases.

Topics: Arthritis, Rheumatoid; Cell Communication; Chemokine CCL2; Chemokine CCL20; Crohn Disease; Female; Gene Expression Regulation; Granulocyte-Macrophage Colony-Stimulating Factor; Humans; Interferon-gamma; Interleukin-17; Interleukin-8; Male; Neutrophil Infiltration; Neutrophils; Receptors, CCR2; Receptors, CCR6; Receptors, Interleukin; Synovial Fluid; T-Lymphocytes, Helper-Inducer; Tumor Necrosis Factor-alpha

Recent insights into the pathogenesis of Crohn's disease (CD) point to an important role of the mucosal barrier and intestinal microflora that may induce a chronic inflammation after crossing the intestinal barrier. The first detected susceptibility gene for CD, NOD2, is a pattern recognition receptor (PRR) for the recognition of the bacterial cell wall component muramyldipeptide (MDP). Binding of MDP to NOD2 is followed by activation of proinflammatory pathways mainly regulated by nuclear factor kappa B (NF-kappaB). In this study we investigated whether impaired recognition of MDP via NOD2 variants is associated with increased bacterial translocation across the epithelial barrier and whether this is followed by increased or decreased NF-kappaB activation.. NOD2 variants were analyzed in 36 CD patients and 30 controls. Endotoxin was stained by immunohistochemistry in 30 intestinal biopsies from patients carrying NOD2 variants (NOD2-mut) or being NOD2 wildtype (WT). Junctional proteins were visualized by immunofluorescence and quantified by Western blotting. NF-kappaB activation was analyzed by immunohistochemistry in specimens from NOD2-WT and NOD2-mut CD and control patients.. We demonstrated the increased presence of endotoxin in the mucosal lamina propria of CD patients carrying NOD2 variants. This was associated with an altered composition of epithelial cell-cell contacts. Patients carrying NOD2 variants displayed increased NF-kappaB activation in the mucosa.. This study for the first time demonstrates that translocation of luminal bacteria and/or bacterial products into the intestinal mucosa is increased in patients carrying NOD2 variants, leading to higher activation of proinflammatory signaling cascades.

Topics: Acetylmuramyl-Alanyl-Isoglutamine; Bacterial Translocation; beta Catenin; Cadherins; Claudins; Crohn Disease; Endotoxins; Humans; Intercellular Junctions; Interleukin-8; Membrane Proteins; Mucous Membrane; NF-kappa B; Nod2 Signaling Adaptor Protein; Occludin

Growing evidence indicates that innate immunity, including toll-like receptor (TLR) signalling, plays a role in inflammatory bowel disease (IBD). This may also apply in the case of TLR-8, which has recently been shown to reverse the immunosuppressive function of regulatory T cells. However, the role of TLR-8 in IBD is currently unknown, and therefore we investigated the expression of TLR-8 and its natural antagonist, Tollip, in normal and inflamed human gut, and examined whether the receptor is functionally active.. TLR-8 and Tollip mRNA expression were measured in colonic epithelial cells (CEC) and lamina propria mononuclear cells (LPMNC) by quantitative polymerase chain reaction. TLR-8 protein expression was visualized in whole biopsy specimens by indirect immunofluorescence microscopy. Cellular localization of TLR-8 protein was assessed by immuno-electron microscopy. IL-8 secretion was measured by ELISA after stimulation with TLR-8 ligand.. TLR-8 mRNA and protein expression were substantially up-regulated in CEC from inflamed mucosa from patients with ulcerative colitis (approximately 350-fold, p<0.01) and Crohn's disease (approximately 45-fold, p<0.05) compared to controls. TLR-8 proteins resided on the luminal surface membrane and in intracellular organelles. Tollip was not increased in CEC from IBD patients. CEC from normal mucosa responded to TLR-8 stimulation by secreting IL-8. TLR-8 was expressed only on the mRNA level in LPMNC with no differences between IBD patients and controls.. Expression of TLR-8, but not Tollip, is highly up-regulated in the colonic epithelium from patients with active IBD. Since the receptor is functionally active, our data suggest that TLR-8 signalling is important in the pathogenesis of IBD.

Topics: Adolescent; Adult; Aged; Colitis, Ulcerative; Crohn Disease; Epithelial Cells; Female; Gene Expression; Humans; Inflammatory Bowel Diseases; Interleukin-8; Intestinal Mucosa; Intracellular Signaling Peptides and Proteins; Male; Middle Aged; Toll-Like Receptor 8; Up-Regulation

Ulcerative colitis (UC) mainly affects the colon and rectum, whereas the chronic inflammatory process in Crohn's disease (CD) can affect any part of the gastrointestinal tract. Recently, however, upper gastrointestinal lesions have been reported in UC patients. In this study, we investigated the immunological status of the stomach in UC or CD patients.. 26 patients each with UC, CD or functional dyspepsia (FD) underwent diagnostic upper gastrointestinal endoscopy, and biopsy specimens were obtained from the gastric antrum. The contents of interleukin (IL)-6 and IL-8 in the organ culture supernatants of antral mucosal tissues were measured with enzyme-linked immunosorbent assay.. Endoscopically abnormal findings in the stomach were more frequent in CD than in UC or FD patients. Mononuclear cell infiltration and IL-6 production in the gastric antrum did not significantly differ between UC and FD patients, but were higher in those with CD. There was no significant difference in neutrophil infiltration or IL-8 production between UC, CD, and FD patients.. UC patients did not show the immunological abnormalities in the stomach seen in CD patients.

Topics: Adolescent; Adult; Colitis, Ulcerative; Crohn Disease; Endoscopy, Gastrointestinal; Female; Gastric Mucosa; Humans; Interleukin-6; Interleukin-8; Male; Neutrophil Infiltration; Organ Culture Techniques; Stomach

Non-obese gallstone patients exhibit a diminished expression of apical sodium-dependent bile acid transporter (ASBT) in terminal ileum. Crohn's ileitis demonstrates a significant downregulation of this transporter.. To test whether subclinical ileal inflammation contributes to gallstone disease.. Biopsies from terminal ileum of female subjects with gallstone disease (n = 7), active Crohn's disease (n = 17) and controls (n = 22) were investigated. mRNA expression of ASBT, tumor necrosis factor-alpha (TNF-alpha), interleukin (IL)-1beta, IL-8, c-jun and c-fos was measured. c-jun and c-fos protein levels were determined and hematoxylin and eosin staining was applied for ileal histology.. ASBT expression was comparably low both in gallstone (47% of controls, p = 0.0093) and Crohn's disease (42% of controls, p = 0.0008). In gallstone disease there was a non-significant trend towards elevated TNF-alpha and IL-1beta, but all cytokines were increased in active Crohn's disease. c-jun and c-fos were slightly diminished in patients with gallstones. Neither cytokines nor transcription factors correlated significantly with ASBT. The gallstone-associated ileal biopsies exhibited no histological inflammation.. Although the expression of ASBT was similarly diminished in both gallstone and Crohn's disease, subclinical ileal inflammation does not appear to be relevant in gallstone patients. The mechanisms of transcriptional repression of ASBT in both diseases are apparently different.

Topics: Adult; Aged; Case-Control Studies; Crohn Disease; Female; Gallstones; Humans; Ileitis; Ileum; Inflammation Mediators; Interleukin-1beta; Interleukin-8; Middle Aged; Organic Anion Transporters, Sodium-Dependent; Proto-Oncogene Proteins c-fos; Proto-Oncogene Proteins c-jun; RNA, Messenger; Symporters; Tumor Necrosis Factor-alpha

To measure the serum levels of neutrophils chemokine granulocyte chemotactic protein-2 (GCP-2) and interleukin-8 (IL-8) in Crohn's disease (CD) and ulcerative colitis (UC) patients and compare them with serum levels of growth-related oncogene (GRO-alpha).. Forty-two patients with inflammatory bowel disease (24 CD and 18 UC) and 38 matched healthy subjects were recruited. Their serum GCP-2, IL-8 and GRO-alpha were measured by a specific enzyme immunoassay kit.. The serum levels of GCP-2 were significantly higher in the CD than the UC patients but lower than in the healthy subjects. The GCP-2 in the UC patients were significantly lower than in the healthy subjects. The GRO-alpha levels were significantly higher in the IBD patients than in the healthy subjects. The IL-8 levels were under the detectable limit in both the IBD and the healthy subjects.. In this group of patients, GCP-2 did not participate in the inflammatory response in IBD. GRO-alpha could be an important factor that enhances the inflammatory state in IBD.

Topics: Adult; Chemokine CXCL1; Chemokine CXCL6; Colitis, Ulcerative; Crohn Disease; Humans; Immunoenzyme Techniques; Interleukin-8

Acute appendicitis (AA) is the most common life-threatening surgical emergency in pediatrics. To characterize the nature of the inflammatory response in AA, gene expression profiles were generated. We found remarkable uniformity in the genes that were differentially expressed between patients with appendicitis and control groups. Sixty-four probe sets were differentially expressed in samples from patients with both severe and mild appendicitis compared to control samples, and within this group we were able to identify four dominant clusters. Interestingly, expression levels of interleukin (IL)-8 significantly correlated with histologic score, and expression of IL-8 protein was observed within both neutrophils and mononuclear cells by immunohistochemistry, suggesting a possible role in the etiology of appendicitis. Although there was some overlap between genes reported to be differentially expressed in Crohn's disease (CD) and those observed in AA, differential expression of genes involved in interferon responses that characterize CD was not observed.

Topics: Acute Disease; Adolescent; Appendicitis; Child; Child, Preschool; Crohn Disease; Female; Gene Expression Profiling; Humans; Interleukin-8; Leukocytes, Mononuclear; Male; Neutrophils

The chronic inflammatory process in patients with Crohn's disease (CD) may affect any part of the gastrointestinal (GI) tract. The pathogenesis of CD involves immunological abnormalities, including deficient or excessive expression of cytokines. We examined Helicobacter pylori infection status, endoscopic and histopathological findings, and cytokine production in the duodenum of CD patients in comparison with controls.. Thirty-eight CD patients underwent diagnostic upper GI endoscopy. Twelve age- and sex-matched health checkup examinees were used as controls. H. pylori infection status was assessed by the (13)C-urea breath test. At the time of endoscopy, two biopsy specimens each were obtained from the second portion of the duodenum, one for hematoxylin-eosin staining and immunohistochemical analysis with anti-CD68 antibody, and one for in vitro organ culture. Interleukin (IL)-6 and -8 levels were measured in organ culture supernatant by enzyme-linked immunosorbent assay.. H. pylori infection was significantly (P<0.05) more frequent in controls (42%) than in CD patients (8%). In the duodenum, erosions or ulcers were more frequent in CD patients (53%) than in controls (8%). Mononuclear cell infiltration in the duodenum was more severe in CD patients than in controls and IL-6 production was higher, whereas IL-8 production showed no significant difference. CD68+ cells in the duodenum were more prominent in CD patients than in controls.. H. pylori infection is unlikely in CD patients, but they show immunological abnormalities in the duodenum, possibly from innate immune responses.

Topics: Adolescent; Adult; Antigens, CD; Antigens, Differentiation, Myelomonocytic; Biopsy; Breath Tests; Case-Control Studies; Crohn Disease; Duodenal Ulcer; Duodenoscopy; Duodenum; Helicobacter Infections; Helicobacter pylori; Humans; Immunity, Innate; Interleukin-6; Interleukin-8; Organ Culture Techniques; Urea; Young Adult

Three mutations (R702W, G908R, and 1007fs) of the CARD15/NOD2 gene associate with Crohn's disease (CD). Despite a strong linkage of CD to the inflammatory bowel disease (IBD) 1 region, only 16% of the Finnish CD patients carry 1 of these 3 mutations, pointing to the possibility of yet undetected founder mutations in the genetically isolated Finns. The aim of this study was to screen for CARD15 mutations in Finnish CD patients and to assess their functional consequences and relation to clinical phenotype.. We performed CARD15 mutation screening in 240 CD probands. For functional studies, blood mononuclear cells were cultured alone or with muramyl dipeptide (MDP) and IL-8 levels were determined.. We identified 30 different variants, including 12 new ones. Allele frequencies for the R702W, G908R, and 1007fs mutations were 3.3%, 0.4%, and 4.8%, respectively. The 1007fs variant was the only 1 associated significantly with CD. Five novel variants (R38M, W355X, P727L, W907R, R1019X) were found in 5 patients. The biochemical nature of these new mutations, data obtained by cross-species comparisons, as well as low IL-8 production favors their pathogenic role. All 5 patients with novel mutations presented a complicated form of ileal or ileocolonic disease.. In conclusion, we identified 5 novel CARD15 mutations with an apparent pathophysiological role, but could not identify a putative Finnish founder mutation. It is still possible that regulatory mutations present in the flanking or intronic areas of the CARD15 gene contribute to the genetic susceptibility of CD. Homozygosity or compound heterozygosity for CARD15 gene mutations must be considered especially in complicated CD patients.

Topics: Case-Control Studies; Crohn Disease; Female; Finland; Founder Effect; Genetic Predisposition to Disease; Humans; Interleukin-8; Male; Middle Aged; Mutation; Nod2 Signaling Adaptor Protein; Phenotype; White People

Reduced ileal Paneth cell alpha-defensin expression has been reported to be associated with Crohn's disease, especially in patients carrying NOD2 mutations. The aim of this study was to independently assess whether NOD2, alpha-defensins and Crohn's disease are linked.. Using quantitative real-time polymerase chain reaction (RT-PCR), we measured the mRNA expression levels of key Paneth cell antimicrobial peptides (DEFA5, DEFA6, LYZ, PLA2G2A), inflammatory cytokines [interkelukin 6 (IL6) and IL8], and a marker of epithelial cell content, villin (VIL1) in 106 samples from both affected ileum (inflamed Crohn's disease cases, n = 44) and unaffected ileum (non-inflamed; Crohn's disease cases, n = 51 and controls, n = 11). Anti-human defensin 5 (HD-5) and haematoxylin/eosin immunohistochemical staining was performed on parallel sections from NOD2 wild-type and NOD2 mutant ileal Crohn's disease tissue.. In Crohn's disease patients, DEFA5 and DEFA6 mRNA expression levels were 1.9- and 2.2-fold lower, respectively, in histologically confirmed inflamed ileal mucosa after adjustment for confounders (DEFA5, p<0.001; DEFA6, p = 0.001). In contrast to previous studies, we found no significant association between alpha-defensin expression and NOD2 genotype. HD-5 protein data supports these RNA findings. The reduction in HD-5 protein expression appears due to surface epithelial cell loss and reduced Paneth cell numbers as a consequence of tissue damage.. Reduction in alpha-defensin expression is independent of NOD2 status and is due to loss of surface epithelium as a consequence of inflammatory changes rather than being the inciting event prior to inflammation in ileal Crohn's disease.

Topics: Adult; Aged; alpha-Defensins; Crohn Disease; Female; Gene Expression; Genotype; Group II Phospholipases A2; Humans; Ileum; Immunoenzyme Techniques; Interleukin-6; Interleukin-8; Male; Middle Aged; Muramidase; Nod2 Signaling Adaptor Protein; Paneth Cells; Reverse Transcriptase Polymerase Chain Reaction; RNA, Messenger

Dysregulation of interleukin-8 (IL-8) production has been proposed to contribute to intestinal inflammation in inflammatory bowel disease (IBD) patients. Previous studies, which evaluate adult patients with long-standing or steroid-modulated disease, have reported conflicting results regarding the role of IL-8 in IBD pathogenesis. The present study evaluates IL-8 in colonic organ cultures and sera of newly and previously diagnosed pediatric IBD patients with various degrees of histopathologic activity. Colon and terminal ileum biopsies were obtained from 26 patients with Crohn's disease, 12 with ulcerative colitis, 4 with indeterminate colitis, and 12 age-matched normal controls. IBD patients were additionally characterized as newly or previously diagnosed. Supernatants from organ-cultured lamina propria biopsies and sera were evaluated by ELISA for IL-8 protein. IL-8 increased with degree of histologic inflammation regardless of diagnosis (no pathologic diagnosis, 62.6 ng/ml, interquartile range [IQR] 30.4-94.6 ng/ml; mild, 92.0 ng/ml, IQR 21.9-170.0 ng/ml; moderate, 676.2 ng/ml, IQR 46.4-2967.7 ng/ml; severe, 585.6 ng/ml, IQR 149.7-1602.2 ng/ml; P < 0.01). Lamina propria IL-8 was significantly elevated in moderately and severely inflamed tissue segments (603.26 ng/ml; IQR, 72.15-2240.4 ng/ml) compared to noninflamed and mildly inflamed segments (67.70 ng/ml; IQR, 30.38-124.1 ng/ml; P = 0.0009). There was no significant trend in IL-8 concentration when compared by clinical diagnosis. No significant difference was found in IL-8 concentrations in organ cultures from newly diagnosed patients versus those from previously diagnosed patients. There was no significant correlation between serum IL-8 concentration and organ culture IL-8 concentration. We conclude that higher concentrations of IL-8 are found in more histologically inflamed tissue segments from pediatric IBD patients. IL-8 does not appear to be associated with clinical IBD subtype. IL-8 appears to be an integral part of both early and established mucosal inflammation in pediatric IBD patients. These findings suggest that IL-8-specific therapies may universally modify inflammatory activity in IBD patients.

Topics: Adolescent; Adult; Case-Control Studies; Child; Child, Preschool; Colitis, Ulcerative; Colon; Crohn Disease; Enzyme-Linked Immunosorbent Assay; Female; Humans; Ileum; Inflammatory Bowel Diseases; Interleukin-8; Intestinal Mucosa; Linear Models; Male; Mucous Membrane; Organ Culture Techniques; Philadelphia; Severity of Illness Index

Marine oil-derived n-3 fatty acids have been shown to stimulate intestinal Ca absorption in animal studies, but the effects of such fatty acids on Ca absorption in human subjects are relatively unknown. In particular, n-3 fatty acids may be of therapeutic value for some Crohn's disease patients who experience Ca malabsorption. Therefore, the aim of the present study was to investigate the effect of 20 : 5n-3 and 22 : 6n-3 on transepithelial Ca transport across monolayers of healthy Caco-2 cells as well as of TNF-alpha-treated Caco-2 cells (an in vitro model of Crohn's disease). Caco-2 cells were seeded onto permeable filter supports and allowed to differentiate into monolayers, which were treated with 80 microM-20 : 5n-3, 80 microM-22 : 6n-3, or 40 microM-20 : 5n-3 + 40 microM-22 : 6n-3 for 6 or 8 d, with or without co-treatment with TNF-alpha (10 ng/ml) (n 11-15 monolayers per treatment). On day 16, transepithelial and transcellular transport of 45Ca and fluorescein transport (a marker of paracellular diffusion) were measured. Treatment of healthy and inflamed Caco-2 cells with 20 : 5n-3, 22 : 6n-3 and both fatty acids combined for 8 d significantly (P < 0.005-0.01) increased total transepithelial Ca transport compared with that in control, effects which were mediated by an enhanced rate of transcellular Ca transport. The effects of n-3 fatty acids on Ca absorption after 6 d were less clear-cut. In conclusion, the present in vitro findings highlight the need to investigate the effect of marine oil-based n-3 fatty acids on Ca absorption in vivo in studies of healthy human subjects as well as of Crohn's disease patients.

Topics: Biological Transport; Caco-2 Cells; Calcium; Cell Survival; Crohn Disease; Electric Impedance; Fatty Acids, Omega-3; Humans; Interleukin-8; Intestinal Absorption; Models, Biological; Tumor Necrosis Factor-alpha

NOD2 plays an important role in the innate immunity of the intestinal tract. By sensing the muramyl dipeptide (MDP), a bacterial wall component, NOD2 triggers the NF-kappaB signaling pathway and promotes the release of proinflammatory cytokines such as interleukin-8. Mutations in Nod2 (1007FS, R702W, G908R) impinge on NOD2 functions and are associated with the pathogenesis of Crohn disease, a chronic inflammatory bowel disease. Although NOD2 is usually described as a cytosolic receptor for MDP, the protein is also localized at the plasma membrane, and the 1007FS mutation delocalizes NOD2 to the cytoplasm (Barnich, N., Aguirre, J. E., Reinecker, H. C., Xavier, R., and Podolsky, D. K. (2005) J. Cell Biol. 170, 21-26; McDonald, C., Chen, F. F., Ollendorff, V., Ogura, Y., Marchetto, S., Lecine, P., Borg, J. P., and Nunez, G. (2005) J. Biol. Chem. 280, 40301-40309). In this study, we demonstrate that membrane-bound versions of NOD2 and Crohn disease-associated mutants R702W and G908R are capable of responding to MDP and activating the NF-kappaB pathway from this location. In contrast, the 1007FS mutant remains unable to respond to MDP from the plasma membrane. We also show that NOD2 promotes the membrane recruitment of RICK, a serine-threonine kinase involved in NF-kappaB activation downstream of NOD2. Furthermore, the artificial attachment of RICK at the plasma membrane provokes a constitutive and strong activation of the NF-kappaB pathway and secretion of interleukin-8 showing that optimal RICK activity depends upon its subcellular localization. Finally, we show that endogenous RICK localizes at the plasma membrane in the THP1 cell line. Thus, our data suggest that NOD2 is responsible for the membrane recruitment of RICK to induce a regulated NF-kappaB signaling and production of proinflammatory cytokines.

Topics: Acetylmuramyl-Alanyl-Isoglutamine; Animals; Caco-2 Cells; Cell Membrane; Crohn Disease; Dogs; Humans; Inflammation; Interleukin-8; Membrane Proteins; Mutation, Missense; NF-kappa B; Nod2 Signaling Adaptor Protein; Protein Transport; Receptor-Interacting Protein Serine-Threonine Kinase 2; Signal Transduction

Urocortin II (UcnII) is a neuropeptide that binds with high affinity to the corticotropin-releasing hormone receptor 2 (CRHR2) in peripheral tissues. UcnII is synthesised in the intestine, but its role in human intestinal inflammation is largely unknown.. Responses of human colonic epithelial cells expressing CRHR2 to stimulation by UcnII were measured using ELISA, western blot analysis, real-time reverse transcription-PCR (RT-PCR) and interleukin (IL)8 promoter activity. Expression levels of CRHR2 and UcnII in human colitis were determined by immunofluorescence and real-time RT-PCR in mucosal biopsies from patients with Crohn's and ulcerative colitis, and in human intestinal xenografts after exposure to Clostridium difficile toxin A.. It is reported here that expression of CRHR2 mRNA and protein in human colonic epithelial cells (HT-29) are increased by exposure to C difficile toxin A or tumour necrosis factor (TNF)alpha. Stimulation of non-transformed NCM460 colonocytes overexpressing CRHR2alpha receptor with UcnII resulted in a time- and concentration-dependent increase in IL8 production. UcnII stimulation also led to activation of nuclear factor-kappaB (NF-kappaB) and mitogen-acivated protein (MAP) kinase in these cells, as evidenced by degradation of IkappaBalpha and phosphorylation of the p65 subunit of NF-kappaB and extracellularly regulated kinase (ERK) 1/2. Furthermore, expression of UcnII and CRHR2 mRNA was increased in mucosal samples of patients with inflammatory bowel disease, and after exposure of human intestinal xenografts to C difficile toxin A.. These results suggest that UcnII has pro-inflammatory effects in human intestinal cells via the CRHR2alpha receptor and may play an important role in the pathophysiology of colitis in humans.

Topics: Animals; Bacterial Toxins; Cell Line; Colitis; Colitis, Ulcerative; Colon; Corticotropin-Releasing Hormone; Crohn Disease; Enterotoxins; Epithelial Cells; Gene Expression Regulation; Humans; Interleukin-8; Intestines; Mice; Mice, SCID; Mitogen-Activated Protein Kinases; NF-kappa B; Receptors, Corticotropin-Releasing Hormone; RNA, Messenger; Transplantation, Heterologous; Tumor Necrosis Factor-alpha; Urocortins

To modify the skin window technique for extended analysis of acute inflammatory responses in humans, and demonstrate its applicability for investigating disease.. 15 healthy subjects and 5 Crohn's patients.. Skin windows, created by dermal abrasion, were overlaid for various durations with filter papers saturated in saline, 100 ng/ml muramyl dipeptide (MDP) or 10 microg/ml interleukin-8 (IL-8).. Exuded leukocytes were analyzed by microscopy, immunoblot, DNA-bound transcription factor arrays and RT-PCR. Inflammatory mediators were quantified by ELISA.. Infiltrating leukocytes were predominantly neutrophils. Numerous secreted mediators were detectable. MDP and IL-8 enhanced responses. Many signalling proteins were phosphorylated with differential patterns in Crohn's patients, notably PKC alpha/beta hyperphosphorylation (11.3 +/- 3.1 vs 1.2 +/- 0.9 units, P < 0.02). Activities of 44 transcription factors were detectable, and sufficient RNA isolated for expression analysis of over 400 genes.. The modifications enable broad characterisation of inflammatory responses and administration of exogenous immunomodulators.

Topics: Acetylmuramyl-Alanyl-Isoglutamine; Acute Disease; Adjuvants, Immunologic; Case-Control Studies; Cell Movement; Crohn Disease; Enzyme-Linked Immunosorbent Assay; Gene Expression Profiling; Gene Expression Regulation; Humans; Immunologic Factors; Inflammation; Interleukin-8; Leukocytes; Neutrophils; Reverse Transcriptase Polymerase Chain Reaction; Skin; Skin Window Technique; Transcription Factors

The expression of CCL20 (MIP-3alpha), which chemoattracts leukocytes to sites of inflammation, has been shown in intestinal epithelial cells (IEC). Aim of this study was to analyze the role of the CCL20 receptor CCR6 in IEC and colorectal cancer (CRC) cells. Expression of CCR6 and CCL20 was analyzed by RT-PCR and immunohistochemistry. Signaling was investigated by Western blotting, proliferation by MTS assays and chemotactic cell migration by wounding assays. The effect of CCL20 on Fas-induced apoptosis was determined by flow cytometry. CCR6 and its ligand CCL20 are expressed in IEC. Moreover, CRC and CRC metastases express CCR6, which is upregulated during IEC differentiation. Stimulation of IEC with CCL20 and proinflammatory stimuli (TNF-alpha, IL-1beta, LPS) significantly upregulates CCL20 mRNA expression. CCL20 expression was significantly increased in inflamed colonic lesions in Crohn's disease and correlated significantly with the IL-8 mRNA expression in these lesions (r = 0.71) but was downregulated in CRC metastases. CCL20 activated Akt, ERK-1/2, and SAPK/JNK MAP kinases and increased IL-8 protein expression. The CCL20 mediated activation of these pathways resulted in a 2.6-fold increase of cell migration (P = 0.001) and in a significant increase of cell proliferation (P < 0.05) but did not influence Fas-induced apoptosis. In conclusion, IEC and CRC express CCL20 and its receptor CCR6. CCL20 expression is increased in intestinal inflammation, while CCR6 is upregulated during cell differentiation. CCR6 mediated signals result in increased IEC migration and proliferation suggesting an important role in intestinal homeostasis and intestinal inflammation by mediating chemotaxis of IEC but also in mediating migration of CRC cells.

Topics: Caco-2 Cells; Cell Differentiation; Cell Line, Tumor; Cell Movement; Cell Proliferation; Chemokine CCL20; Chemokines, CC; Colorectal Neoplasms; Crohn Disease; Cytokines; Fas Ligand Protein; HCT116 Cells; HT29 Cells; Humans; Inflammation; Interleukin-8; Intestinal Mucosa; Macrophage Inflammatory Proteins; MAP Kinase Kinase 1; MAP Kinase Kinase 4; Membrane Glycoproteins; Mitogen-Activated Protein Kinase 1; Mitogen-Activated Protein Kinase 3; Phosphorylation; Proto-Oncogene Proteins c-akt; Receptors, CCR6; Receptors, Chemokine; Signal Transduction; Tumor Necrosis Factors

The cause of Crohn's disease has not been mechanistically proven. We tested the hypothesis that the disease is a form of immunodeficiency caused by impaired innate immunity.. We investigated inflammatory responses in patients and controls by quantifying neutrophil recruitment and cytokine production after acute trauma, interleukin 8 secretion by cultured monocyte-derived macrophages after exposure to inflammatory mediators, and local inflammatory and vascular changes in response to subcutaneous injection of heat-killed Escherichia coli.. In patients with Crohn's disease, trauma to rectum, ileum, or skin led to abnormally low neutrophil accumulation (differences from healthy individuals of 79%, n=8, p=0.0003; 57%, n=3, p=0.05; 50%, n=13, p<0.0001, respectively) and lower production of proinflammatory interleukin 8 (63%, n=7, p=0.003; 63%, n=3, p=0.05; 45%, n=8, p<0.0001) and interleukin 1beta (50%, n=8, p=0.0005). Interleukin 8 secretion by cultured macrophages was reduced after exposure to acute wound fluid (38%, n=50, p<0.0001), C5a (48%, n=41, p=0.0005), or tumour necrosis factor alpha (52%, n=27, p<0.0001). Local inflammatory reaction to inoculation with E coli was attenuated, as quantified by changes in bloodflow (ileal disease 50%, n=6, p=0.01; colonic disease 77%, n=6, p=0.0003). This response was mediated by nitric oxide in controls, was increased by sildenafil in patients, and was not related to CARD15 genotype.. In Crohn's disease, a constitutionally weak immune response predisposes to accumulation of intestinal contents that breach the mucosal barrier of the bowel wall, resulting in granuloma formation and chronic inflammation. Polymorphisms in CARD15 do not underlie this phenotype, but incapacitate the NOD2 pathway that can compensate for impairment of innate inflammation. Current treatment of secondary chronic inflammation might exaggerate the underlying lesion and promote chronic disease.

Topics: Case-Control Studies; Crohn Disease; Humans; Inflammation; Inflammation Mediators; Interleukin-8; Rectum

Both NOD2/CARD15 alleles are mutated in approximately 10% of Crohn's disease patients, causing loss of functional responses to low-dose muropeptide agonists. We hypothesized that NOD2 mutations may also impair NOD1/CARD4 responses, supported by data suggesting NOD2 1007fs/1007fs patients had reduced responses to a putative NOD1 agonist, diaminopimelic acid-containing muramyl tripeptide (M-TriDAP). We measured peripheral blood mononuclear cell (n = 8 NOD2 wild type, n = 4 1007fs/1007fs, n = 6 702Trp/1007fs, n = 5 702Trp/702Trp, n = 3 908Arg/1007fs) responses to NOD1 agonists alone (IL-8/TNF-alpha), and agonist enhancement of lipopolysaccharide (LPS) responses (IL-1beta). Significant responses were seen with M-TriDAP at 10 nM (as with NOD2 agonists), but only at > or =100 nM with FK565/TriDAP. M-TriDAP induced IL-8/TNF-alpha secretion, and enhancement of LPS IL-1beta responses was significantly reduced between NOD2 double mutation carriers versus healthy controls, whereas there was no difference with FK565 or TriDAP stimulation, or between 1007fs/1007fs cells and other genotypes. M-TriDAP contains both NOD1 (gamma-D-Glu-mesoDAP) and NOD2 (MurNAc-L-Ala-D-Glu) minimal structures whereas FK565/TriDAP contain only NOD1 activating structures. M-TriDAP has dual NOD1/NOD2 agonist activity in primary cells, possibly due to different intracellular peptidoglycan processing compared to the HEK293 cell system typically used for agonist specificity studies. Responses to specific NOD1 agonists are unaffected by NOD2 genotype, suggesting independent action of the NOD1 and NOD2 pathways.

Topics: Acetylmuramyl-Alanyl-Isoglutamine; Adaptor Proteins, Signal Transducing; Crohn Disease; Enzyme-Linked Immunosorbent Assay; Genotype; Humans; Interleukin-1; Interleukin-8; Intracellular Signaling Peptides and Proteins; Lipopolysaccharides; Nod1 Signaling Adaptor Protein; Nod2 Signaling Adaptor Protein; Peptidoglycan; Tumor Necrosis Factor-alpha

Expression of the caspase-activating adaptor ASC was reported to be associated with the production of IL-8, a primary mediator of mucosal inflammation, in vitro. However, the significance of the ASC-mediated IL-8 production in primary tissues has remained poorly understood. Primary intestinal mucosa isolated from surgically resected ileum or colon was incubated with several concentrations of LPS or left untreated. ASC expression was up-regulated at 2 h after stimulation with low doses of LPS (1-10 ng/ml), and was associated with IL-8 secretion, and then was down-regulated later. In contrast, ASC expression remained at the basal level in mucosal tissue treated with a high dose of LPS (1000 ng/ml). Interestingly, in mucosa from several cases of Crohn's disease, ASC was highly expressed without stimulation, and IL-8 was stably secreted with no regulation by LPS. These findings revealed that ASC expression correlates with IL-8 secretion and may play an important role in maintaining mucosal homeostasis.

Topics: CARD Signaling Adaptor Proteins; Crohn Disease; Cytoskeletal Proteins; Gene Expression Regulation; Homeostasis; Humans; Interleukin-8; Intestinal Mucosa; Lipopolysaccharides; Tissue Culture Techniques; Tumor Necrosis Factor-alpha

Crohn's disease is strongly associated with double mutations in NOD2/CARD15. Three common mutations (Arg702Trp, Gly908Arg, Leu1007fs) impair innate immune responses to bacterial muramyl dipeptide. Rare NOD2 variants occur, but it is difficult to both identify them and assess their functional effect. We assessed the true frequency of defective muramyl dipeptide sensing in Crohn's disease and developed a rapid diagnostic assay.. An ex vivo assay was established and validated based on muramyl dipeptide stimulation of peripheral blood mononuclear cell cytokine production. Muramyl dipeptide-induced enhancement of interleukin (IL)-8 secretion and synergistic increase in lipopolysaccharide-induced IL-1beta secretion were studied. Assay results were compared with NOD2 genotype status (3 common mutations and rare variants) in 91 individuals including a prospective cohort of 49 patients with Crohn's disease.. The assay was highly sensitive and specific for detection of profound defects in muramyl dipeptide sensing caused by double NOD2 mutations (IL-8 P = 0.0002; IL-1beta P = 0.0002). Disease state, active inflammation, or concurrent use of immunosuppressive medication did not influence results. Healthy NOD2 heterozygotes had modest impairment of muramyl dipeptide induced IL-8 secretion (P = 0.003). Only 1 of 7 patients with Crohn's disease with both a common mutation and a rare variant had a profound muramyl dipeptide-sensing defect.. Profound defects in muramyl dipeptide sensing were found in 10% of patients with Crohn's disease. Defects were caused exclusively by inherited mutations in NOD2. The ex vivo assay has multiple potential applications as a clinical diagnostic tool to distinguish patients with muramyl dipeptide-sensing defects and for research investigation.

Topics: Acetylmuramyl-Alanyl-Isoglutamine; Crohn Disease; Cytokines; Enzyme-Linked Immunosorbent Assay; Genotype; Heterozygote; Humans; Immunosuppressive Agents; Inflammation; Interleukin-1beta; Interleukin-8; Lipopolysaccharides; Monocytes; Mutation; Sensitivity and Specificity

Topics: Case-Control Studies; Chemokine CCL2; Crohn Disease; Humans; Inflammation; Interleukin-8; Intestinal Mucosa

Topics: Adult; Child; Colitis, Ulcerative; Crohn Disease; Humans; Interleukin-8

Nucleotide binding oligomerisation domain 2 (NOD2; also known as CARD15) mutations are associated with Crohn's disease but how mutations cause disease is poorly understood. Innate immune responses are reportedly enhanced by combined NOD2 ligand (muramyl dipeptide, MDP) and Toll-like receptor 4 ligand (TLR4, lipopolysaccharide) stimulation. Intestinal TLR signalling has a dual role-maintaining intestinal homeostasis and protection from injury as well as initiating inflammatory responses. TLR9 is functional in the intestinal epithelium where it is most strongly expressed in Paneth cells.. To study possible interactions between CpG DNA (TLR9 ligand) and MDP using primary human cells of differing NOD2 genotypes.. NOD2 wild-type healthy controls (n = 7) and NOD2 homozygous Crohn's disease patients (n = 19), age and sex matched.. Peripheral blood mononuclear cells were stimulated with CpG DNA and MDP. Cytokines were measured by enzyme linked immunosorbent assay.. Tumour necrosis factor alpha (TNF-alpha) and interleukin 8 (IL-8) responses to CpG DNA were similar in NOD2 wild-type and homozygous mutant cells. Concomitant NOD2 stimulation had a marked synergistic effect on CpG DNA induced TNF-alpha responses at 10-100 ng/ml MDP. A mean 2.1-fold increase in CpG DNA induced TNF-alpha responses and a mean 3.7-fold increase in IL-8 responses were observed in NOD2 wild-type cells with 10 ng/ml MDP. This effect was abolished in NOD2 homozygous cells.. NOD2 stimulation normally enhances innate immune responses to CpG DNA. This marked synergistic effect is lost in Crohn's disease patients homozygous for NOD2 mutations, with implications for TLR mediated intestinal homeostasis and inflammation.

Topics: Acetylmuramyl-Alanyl-Isoglutamine; Adult; Blotting, Western; Cells, Cultured; CpG Islands; Crohn Disease; Drug Synergism; Enzyme-Linked Immunosorbent Assay; Female; Humans; Immunity, Mucosal; Interleukin-8; Intestinal Mucosa; Intracellular Signaling Peptides and Proteins; Ligands; Male; Membrane Glycoproteins; Middle Aged; Mutation; Nod2 Signaling Adaptor Protein; Receptors, Cell Surface; Reverse Transcriptase Polymerase Chain Reaction; Toll-Like Receptor 4; Toll-Like Receptor 9; Toll-Like Receptors; Tumor Necrosis Factor-alpha

Recognition of repeat CpG motifs, which are common in bacterial, but not in mammalian, DNA, through Toll-like receptor (TLR)9 is an integral part of the innate immune system. As the role of TLR9 in the human gut is unknown, we determined the spectrum of TLR9 expression in normal and inflamed colon and examined how epithelial cells respond to specific TLR9 ligand stimulation. TLR9 expression was measured in human colonic mucosal biopsies, freshly isolated human colonic epithelial cells and HT-29 cells by reverse transcriptase-polymerase chain reaction or Western blotting. Colonic epithelial cell cultures were stimulated with a synthetic CpG-oligodeoxynucleotide (ODN), exhibiting strong immunostimulatory effects in B cells. Interleukin (IL)-8 secretion was determined by enzyme-linked immunosorbent assay, nuclear factor-kappaB (NF-kB) activity by electrophoretic mobility shift assay and IkB phosphorylation by Western blotting. TLR9 mRNA was equally expressed in colonic mucosa from controls (n = 6) and patients with ulcerative colitis or Crohn's disease disease (n = 13). HT-29 cells expressed TLR9 mRNA and protein and responded to CpG-ODN (P < 0.01), but not to non-CpG-ODN stimulation, by secreting IL-8, apparently in the absence of NF-kB activation. Primary epithelial cells isolated from normal human colon expressed TLR9 mRNA, but were completely unresponsive to CpG-ODN stimulation in vitro. In conclusion, differentiated human colonic epithelial cells are unresponsive to TLR9 ligand stimulation in vitro despite spontaneous TLR9 gene expression. This suggests that the human epithelium is able to avoid inappropriate immune responses to luminal bacterial products through modulation of the TLR9 pathway.

Topics: Adult; Aged; Aged, 80 and over; Blotting, Western; Cell Line, Transformed; Cells, Cultured; Colitis, Ulcerative; Colon; Crohn Disease; Epithelial Cells; Female; Gene Expression Regulation; Humans; I-kappa B Proteins; Interleukin-8; Intestinal Mucosa; Male; Membrane Glycoproteins; Middle Aged; NF-kappa B; Oligodeoxyribonucleotides; Receptors, Cell Surface; Reverse Transcriptase Polymerase Chain Reaction; RNA, Messenger; Toll-Like Receptor 9; Toll-Like Receptors

Previously we reported that linoleic acid (LA), but not oleic acid, caused a marked increase in the secretion of IL-8 by Crohn's human intestinal smooth muscle (HISM) cells. Antioxidants inhibited this response, implicating a role for oxidative stress and NF-kappaB, a transcription factor for IL-8 that is activated by oxidative stress. In this study, we examined two mechanisms whereby LA, the dietary precursor for arachidonic acid (AA), could increase the production of IL-8 via activation of AA pathways: 1) by generation of reactive oxygen species by the AA-pathway enzymes to activate NF-kappaB or 2) by AA metabolites. Normal and Crohn's HISM cells were exposed to LA, oxidizing solution (Ox), or oxidizing solution enriched with LA (OxLA). Exposure of cells to Ox or OxLA induced oxidative stress as determined by thiobarbituric acid reactive substances. In normal cells, Ox but not LA activated NF-kappaB as determined by transfection experiments and Western blot. In Crohn's cells, NF-kappaB was spontaneously activated and was not further activated by Ox or LA. In contrast, TNF-alpha markedly increased activation of NF-kappaB in both normal and Crohn's cells. These results indicated that LA did not increase IL-8 by activating NF-kappaB, so we evaluated the second mechanism of an effect of AA metabolites. In normal cells, OxLA, but not LA, markedly stimulated IL-8, whereas in Crohn's cells, both OxLA and LA stimulated IL-8. OxLA, also stimulated production of AA metabolites leukotriene B(4) (LTB(4)), PGE(2), and thromboxane B(2) (TXB(2)) by normal and Crohn's cells. To determine whether AA metabolites mediated the IL-8 response, cells were treated with OxLA plus indomethacin (Indo), a cyclooxygenase inhibitor, and nordihydroguaiaretic acid (NDGA), a lipoxygenase inhibitor. Both Indo and NDGA blocked the IL-8 response to OxLA. To determine more specifically a role for AA metabolites, AA was used. Similar to OxLA, OxAA stimulated production of IL-8 and AA metabolites. Pinane thromboxane, a selective thromboxane synthase inhibitor and receptor blocker, inhibited OxAA stimulation of TXB(2) and IL-8 in a dose-response manner. MK886, a selective 5-lipoxygenase inhibitor, inhibited OxAA stimulation of LTB(4) and IL-8 also in a dose-response manner. Analysis of specific gene products by RT-PCR demonstrated that HISM cells expressed receptors for both thromboxane and LTB(4). We conclude that AA metabolites mediated the IL-8 response to LA in HISM cells. Both cyclooxyge

Topics: Arachidonic Acid; Blotting, Western; Cells, Cultured; Crohn Disease; Cyclooxygenase Inhibitors; Genes, Reporter; Humans; Indomethacin; Interleukin-8; Intestinal Mucosa; Intestines; Leukotriene B4; Linoleic Acid; Luciferases; Muscle, Smooth; NF-kappa B; Oxidative Stress; Receptors, Thromboxane; RNA, Messenger

The normal gut flora has been implicated in the pathophysiology of inflammatory bowel disease and there is increased interest in the role that stress can play in gut disease. The chemical stressor dinitrophenol (DNP, uncouples oxidative phosphorylation) was injected into the ileum of laparotomized rats and mitochondria structure, epithelial permeability, and inflammatory cell infiltrate were examined 6 and 24 hours later. Monolayers of human colonic epithelial cells (T84, HT-29) were treated with DNP +/- commensal Escherichia coli, followed by assessment of epithelial permeability, bacterial translocation, and chemokine (ie, interleukin-8) synthesis. Delivery of DNP into rat distal ileum resulted in disruption of epithelial mitochondria; similar changes were noted in mildly inflamed ileal resections from patients with Crohn's disease. Also, DNP-treated ileum displayed increased gut permeability and immune cell recruitment. Subsequent studies revealed deceased barrier function, increased bacterial translocation, increased production of interleukin-8, and enhanced mobilization of the transcription factor AP-1 in the model epithelial cell lines exposed to commensal bacteria (E. coli strains HB101 or C25), but only when the monolayers were pretreated with DNP (0.1 mmol/L). These data suggest that enteric epithelia under metabolic stress perceive a normally innocuous bacterium as threatening, resulting in loss of barrier function, increased penetration of bacteria into the mucosa, and increased chemokine synthesis. Such responses could precipitate an inflammatory episode and contribute to existing enteric inflammatory disorders.

Topics: Animals; Bacterial Adhesion; Bacterial Translocation; Cell Membrane Permeability; Cells, Cultured; Crohn Disease; Dinitrophenols; Electrophoretic Mobility Shift Assay; Enzyme-Linked Immunosorbent Assay; Escherichia coli; Humans; Interleukin-8; Intestinal Mucosa; Male; Microscopy, Electron; Mitochondria; Rats; Rats, Sprague-Dawley; Stress, Physiological; Transcription Factor AP-1; Uncoupling Agents

Crohn's disease (CD) is a chronic inflammation affecting the gastrointestinal tract. Three mutations (Arg702Trp, Gly908Arg and Leu1007fsinsC) within the NOD2/CARD15 gene increase CD susceptibility. Here, we define cytokine regulation in primary human mononuclear cells, with muramyl dipeptide (MDP), the minimal NOD2/CARD15 activating component of peptidoglycan. By microarray, MDP induces a broad array of transcripts, including interleukin 1beta (IL-1beta) and interleukin 8 (IL-8). Leu1007fsinsC homozygotes demonstrated decreased transcriptional response to MDP. Electromobility shift assay demonstrated that MDP-induced NF-kappaB activation is mediated via p50 and p65 subunits, but not RelB or c-Rel. In wild-type individuals, MDP-induced IL-8 protein expression with a greater response to high dose (1 micro g/ml) compared with low-dose (10 ng/ml) MDP. At low MDP doses, in all homozygotes, we observed no induction of IL-8 protein. With high doses of MDP, Leu1007fsinsC homozygotes showed no induction. Modest induction of IL-8 protein was observed in Gly908Arg and Arg702Trp homozygotes, indicating varying MDP sensitivity of the CD-associated mutations. In wild-type healthy control, CD and ulcerative colitis individuals, low-dose MDP and TNFalpha alone results in only modest IL-1beta protein induction. With MDP plus TNFalpha, there is a synergistic induction of IL-1beta secretion. In Leu1007fsinsC homozygotes, there is a profound defect in IL-1beta secretion, despite marked induction of IL-1beta mRNA. These findings demonstrate post-transcriptional dependency on the NOD2/CARD15 pathway for IL-1beta secretion with MDP and TNFalpha treatment. Taken together, these studies suggest that a signaling defect of innate immunity to MDP may be an essential underlying defect in the pathogenesis of some CD patients.

Topics: Acetylmuramyl-Alanyl-Isoglutamine; Crohn Disease; Cytokines; DNA Primers; Electrophoretic Mobility Shift Assay; Gene Expression Regulation; Humans; Immunity, Innate; Interleukin-1; Interleukin-8; Intracellular Signaling Peptides and Proteins; Leukocytes, Mononuclear; Microarray Analysis; Mutation; Nod2 Signaling Adaptor Protein; Reverse Transcriptase Polymerase Chain Reaction; Signal Transduction; Tumor Necrosis Factor-alpha

Crohn's disease (CD) and ulcerative colitis (UC) are inflammatory bowel diseases (IBD) that are characterized by chronic intestinal inflammation and a constant influx of leukocytes mediated by pro-inflammatory cytokines and chemokines. The intestinal expression of the CXCR1-binding chemokines IL-8/CXCL8 and GCP-2/CXCL6 and the participation of immunocompetent cells in IBD were evaluated. IL-8 production by peripheral blood mononuclear cells (PBMC) from IBD patients, stimulated with endotoxin, plant lectin or double-stranded RNA, was significantly lowered in patients with CD, but not in UC patients or healthy subjects. The reduced chemokine production by PBMC from IBD patients was both IL-8 and CD specific, but not inducer dependent. In serum, most chemokines remained undetectable, while the levels of those that were measurable remained unaltered in IBD patients. GCP-2, but not ENA-78/CXCL5, nor IL-8, were highly expressed by endothelial cells in inflamed intestinal tissue of IBD patients. In contrast, stimulated endothelial cell cultures produced more IL-8 than GCP-2. The selective GCP-2 staining of endothelial cells at sites of ulcerations suggests that GCP-2, despite its low production capacity in vitro, plays a role in IBD that is different from that of structurally (ENA-78) and functionally (IL-8) related ELR(+) CXC chemokines. Thus, the chemokine network shows complementarity rather than redundancy.

Topics: Chemokine CXCL6; Chemokines, CXC; Crohn Disease; Down-Regulation; Endothelial Cells; Enzyme-Linked Immunosorbent Assay; Humans; Immunohistochemistry; Inflammation; Intercellular Signaling Peptides and Proteins; Interleukin-8; Intestinal Mucosa; Intestines; Leukocytes; Receptors, Interleukin-8A

Mutations in NOD2, a putative intracellular receptor for bacterial peptidoglycans, are associated with a subset of Crohn's disease but the molecular mechanism linking this protein with the disease pathogenesis remains unclear. Human alpha defensins (HD-5 and HD-6) are antibiotic effector molecules predominantly expressed in Paneth cells of the ileum. Paneth cells also express NOD2. To address the hypothesis that the function of NOD2 may affect expression of Paneth cell defensins, we compared their expression levels with respect to NOD2 mutations in Crohn's disease.. Forty five Crohn's disease patients (24 with NOD2 mutations, 21 with wild-type NOD2) and 12 controls were studied. Real time reverse transcription-polymerase chain reaction was performed with mucosal mRNA for HD-5, HD-6, lysozyme, secretory phospholipase A2 (sPLA2), tumour necrosis factor alpha, interleukin 8, and human hypoxanthine phosphoribosyltransferase (housekeeping gene). Immunohistochemistry with anti-HD-5 and histological Paneth cell staining were performed in 10 patients with NOD2 mutations or wild-type genotypes.. Ileal expression of HD-5 and HD-6, but not sPLA2 or lysozyme, were diminished in affected ileum, and the decrease was significantly more pronounced in patients with NOD2 mutations. In the colon, HD-5, HD-6, and sPLA2 were increased during inflammation in wild-type but not in NOD2 mutated patients. In both the colon and ileum, proinflammatory cytokines and lysozyme were unaffected by NOD2 status. Immunohistochemistry identified Paneth cells as the sole source of HD-5.. As alpha defensins are important in the mucosal antibacterial barrier, their diminished expression may explain, in part, the bacterial induced mucosal inflammation and ileal involvement of Crohn's disease, especially in the case of NOD2 mutations.

Topics: Adolescent; Adult; Aged; alpha-Defensins; Colon; Crohn Disease; DNA Mutational Analysis; Gene Expression Regulation; Humans; Ileum; Immunity, Mucosal; Interleukin-8; Intracellular Signaling Peptides and Proteins; Middle Aged; Mutation; Nod2 Signaling Adaptor Protein; Paneth Cells; Polymerase Chain Reaction; RNA, Messenger; Tumor Necrosis Factor-alpha

Mucosal changes in inflammatory bowel disease (IBD) are characterized by ulcerative lesions accompanied by prominent cellular infiltrates in the bowel wall. Chemokines are chemotactic cytokines that are able to promote leukocyte migration to areas of inflammation and are also able to initiate cell activation events. They have recently been implicated in the pathophysiology of many disease states. The aim of this study was to detail the degree and distribution of specific chemokines, interleukin (IL)-8, monocyte chemoattractant protein (MCP)-1, -2, and -3, and macrophage inflammatory protein (MIP)-1alpha and -1beta, in IBD mucosa. Thirty-nine patients were included, ten controls, 20 ulcerative colitis (UC), and nine Crohn's disease (CD), with a range of disease activity. Colonic mucosal biopsies were collected from UC, CD, and control patients and embedded in glycol methacrylate. Two-micrometre-thick sections were cut and stained using immunohistochemistry for chemokine protein expression. Sections were analysed using a light microscope. Expression of all types of chemokine protein was detected in colonic mucosa from both control and IBD patients. Patterns of staining between IBD patients and controls differed significantly, but CD and UC patients demonstrated similar patterns of staining. Individual chemokine expression was found to be significantly up-regulated in IBD when patients were compared with the non-diseased group in all areas of the mucosal sections. Up-regulated chemokine expression correlated with increasing activity of the disease. It is concluded that human colonic chemokine expression is non-selectively up-regulated in IBD. The results supported the hypothesis that the degree of local inflammation and tissue damage in UC and CD is dependent on local expression of specific chemokines within IBD tissues.

Topics: Chemokine CCL2; Chemokine CCL3; Chemokine CCL4; Chemokine CCL7; Chemokine CCL8; Chemokines; Colitis, Ulcerative; Colon; Crohn Disease; Cytokines; Humans; Immunohistochemistry; Interleukin-8; Intestinal Mucosa; Macrophage Inflammatory Proteins; Monocyte Chemoattractant Proteins; Up-Regulation

Crohn's disease is a chronic inflammatory bowel disease (IBD) of unknown etiology. In this study, we investigated the hypothesis that dietary fatty acids, linoleic acid (LA) and oleic acid (OA), could be involved in the inflammatory response through stimulation of the neutrophil chemokine, IL-8.. Human intestinal smooth muscle (HISM) cells were isolated from normal patients and patients with Crohn's disease and cultured for 24h with LA or OA in the presence or absence of oxidative stress. The concentrations of IL-8 were measured in the media and cellular oxidative stress was quantitated by measurement of thiobarbituric acid reactive substances (TBARSs).. Spontaneous production of IL-8 was significantly higher in HISM cells isolated from Crohn's bowel compared to control bowel. LA caused a marked, nine-fold, increase in IL-8 secretion by Crohn's cells, an effect that could be simulated in normal HISM cells by co-incubation of LA with an oxidizing solution (Ox) composed of hypoxanthine+xanthine oxidase+FeSO(4) (OxLA). These effects were inhibited by vitamins C and E. Treatment of Crohn's cells with OxLA did not further increase IL-8 over that of LA alone. The effect of LA alone was not associated with an increase in cellular oxidative stress as quantitated by TBARSs. In contrast to the results with LA, treatment with OA or OxOA did not increase IL-8 in either normal or Crohn's cells. In addition, OA protected Crohn's cells from the increase in TBARSs induced by Ox. In contrast to IL-8, spontaneous production of monocyte chemotactic protein (MCP-1) was significantly lower in Crohn's HISM cells as compared to normal cells and exposure to OxLA did not increase its production.. LA, but not OA, increased the production of IL-8 by HISM cells. These results suggest that replacement of LA by OA in the diet of Crohn's patients and increased intake of a diet rich in antioxidants could be beneficial in decreasing inflammatory activity in Crohn's disease.

Topics: Analysis of Variance; Antineoplastic Agents; Antioxidants; Cell Separation; Crohn Disease; Humans; Interleukin-8; Intestinal Mucosa; Intestines; Linoleic Acid; Lipid Peroxidation; Myocytes, Smooth Muscle; Oleic Acid; Oxidative Stress; Thiobarbituric Acid Reactive Substances; Time Factors; Up-Regulation

The level of macrophage migration inhibitory factor (MIF) and the functions of dendritic cells (DC) are up-regulated in the peripheral blood, and the numbers of MIF-expressing cells and mature DC are increased at the colonic mucosa from patients with ulcerative colitis (UC). However, a functional relationship between MIF and DC, and the role of MIF in the pathogenesis of UC, are not clear. In this study, we showed that a pure population of peripheral blood DC is a new and still unknown source of MIF. DC from UC patients produced significantly higher levels of MIF (17 x 5 +/- 9 x 8 ng/ml, n = 10) compared with patients with Crohns disease (CD) (4 x 6 +/- 2 x 5 ng/ml, n = 5, P< 0 x 01) and control subjects (5 x 0 +/- 2 x 6 ng/ml, n = 10, P< 0 x 01). A double immunofluorescence study revealed the expression of MIF by CD83-positive mature DC at the colonic mucosa from UC patients. Blood DC treated with high amounts of MIF (500 ng/ml) showed a significantly higher stimulatory capacity (43287 +/- 5998 CPM, n = 5) in an allogenic mixed leucocyte reaction compared with untreated DC (27528 +/- 8823 CPM, n = 5, P< 0 x 05). Study of intracellular cytokine expression showed that MIF induced significant levels of interleukin (IL)-1 and IL-8 in monocytes and DC from UC and CD patients. These results showing the capacity of MIF to induce increased functional capacity of DC, and to produce IL-1 and IL-8 from monocytes and DC, indicate a role of MIF in the induction and/or perpetuation of the inflammatory environment in UC.

Topics: Cells, Cultured; Colitis, Ulcerative; Colon; Crohn Disease; Dendritic Cells; Humans; Interleukin-1; Interleukin-6; Interleukin-8; Intestinal Mucosa; Macrophage Migration-Inhibitory Factors; Monocytes; Tumor Necrosis Factor-alpha

Smoking in patients with Crohn's disease is associated with more frequent relapse. The mechanism responsible is unknown but a direct pro-inflammatory action on intestinal mucosa has been postulated. Mucosal inflammation in clinically inactive Crohn's disease predicts forthcoming relapse. Whole gut lavage fluid obtained after bowel cleansing with a polyethylene glycol electrolyte solution is an assessment of gut inflammation and immunity.. To assess whether whole gut lavage fluid interleukin-1beta and interleukin-8 differed between smokers and non-smokers with clinically inactive Crohn's disease.. A total of 34 patients with inactive Crohn's disease (Crohn's disease activity index <150 and whole gut lavage fluid IgG concentration of <10 mg/ml) underwent whole gut lavage with interleukin-1beta and interleukin-8 analysed by enzyme-linked immunosorbent assay. Clinical details and blood markers of inflammation were collected.. In this series, 14 patients smoked (10 females, mean age 44.3+/-14.3 years), 20 did not (12 females, mean age 40.7+/-14.3). Surgical resection was more common in smokers (12/14 vs 8/20, p<0.008). Whole gut lavage fluid IgG was significantly lower in smokers (median 1.5 mg/ml (range 1.0-8.0 mg/ml) vs median 3.5 mg/ml (range 1.0-7.0 mg/ml), p<0.05). Whole gut lavage fluid interleukin-1beta was also lower in smokers [median 14.5 pg/ml (range 2-72 pg/ml) vs 26 pg/ml (range 7-1700 pg/ml)], p<0.03.. Markers of mucosal inflammation in inactive Crohn's disease are lower in smokers than non-smokers. This is against the hypothesis that nicotine exerts a direct pro-inflammatory action via interleukin-1beta and interleukin-8. Further research is required to elucidate the exact mechanisms involved.

Topics: Adult; Aged; Biomarkers; Crohn Disease; Female; Humans; Interleukin-1; Interleukin-8; Intestinal Mucosa; Intestines; Male; Middle Aged; Recurrence; Smoking; Therapeutic Irrigation

It is well known that mucosal concentrations of many pro and anti-inflammatory cytokines are elevated in diseased segments of colon in Crohn's colitis. The present study, showing preliminary results, aims to determine whether the IL-1beta, IL-6 and IL-8 levels are increased throughout the entire colon in patients with Crohn's colitis.. Five patients with active Crohn's colitis and five controls were studied by mucosal biopsies. In the diseased patients IL-1beta, IL-6 and IL-8 levels have been measured in both pathologic and normal appearing colonic mucosa. The concentration of these cytokines was assessed using ELISA and compared. Histological sections were also performed to confirm diseased segment of colon.. The concentrations IL-1beta and IL-8 were much more higher in patients with Crohn's colitis when compared to controls. Moreover IL-1beta and IL-8 were more elevated in uninvolved colonic segments than on diseased segments.. Our results confirm the finding of other authors that, although Crohn's colitis is a segmental disease, the concentration of IL-1beta and IL-8 in mucosal biopsies is increased throughout the entire colon. In particular our study shows that the concentrations of IL-1b and IL-8 is higher in uninvolved than involved colonic segments. These appearances favour the physio-pathologic hypothesis that Crohn's colitis involves the entire colon even when is not clinically or histologically apparent, and they suggest that uninvolved parts of colon may not be free of disease. Further studies are required to better understand the higher levels of cytokines found in macroscopically normal when compared to pathological mucosal in patients with Crohn's colitis.

Topics: Adolescent; Adult; Aged; Biopsy; Crohn Disease; Female; Humans; Interleukin-1; Interleukin-6; Interleukin-8; Male; Middle Aged

The number of eosinophils is increased in the mucosae of the digestive and the respiratory tracts in Crohn disease, even clinically quiescent. The mechanisms underlying this panmucosal eosinophilia are unknown.. The response of blood eosinophils to various chemotactic agents was assessed in 15 patients with clinically quiescent Crohn disease. The results were compared with 15 healthy controls. After purification, eosinophils were placed in Boyden microchambers and the chemotactic effect of PAF (10(-7) M), RANTES (50 ng/ml), IL-5 (0-20 ng/ml), IL-8 (0-50 ng/ml), Eotaxin (0-50 ng/ml) was evaluated. The number of eosinophils in induced sputum of these Crohn disease patients and controls was also assessed and the correlation between chemotaxis and eosinophil count in induced sputum was studied.. PAF and RANTES induced a chemotactic effect both in Crohn disease patients and controls. The chemotactic index was significantly higher in Crohn than controls for PAF (2.09+/-0.24 versus 1.37+/-0.14; P < 0.05) but not RANTES. With IL-5, IL-8 and Eotaxin, there was no detectable chemotactic effect in controls while in Crohn, we observed a significant dose-dependent chemotactic effect. Furthermore, with Eotaxin 50 ng/ml, the chemotactic index was significantly higher in Crohn disease patients than controls (2.42+/-0.18 versus 1.56+/-0.28; P < 0.05). A significant increase in sputum eosinophil count and a significant decrease in sputum macrophage count in Crohn disease were observed. However, there was no correlation between eosinophil chemotaxis and sputum eosinophil count in individual patients.. There is an increased response of blood eosinophils to various chemotactic agents, mainly PAF and Eotaxin, in clinically quiescent Crohn disease. This may participate in the mucosal infiltration by eosinophils in this disease.

Topics: Adult; Chemokine CCL11; Chemokine CCL5; Chemokines, CC; Chemotactic Factors, Eosinophil; Crohn Disease; Cytokines; Eosinophils; Female; Humans; Interleukin-5; Interleukin-8; Male; Middle Aged; Platelet Activating Factor

Trials of maintenance therapy in Crohn's disease are often underpowered, and there is need for objective markers of relapse. We assessed the relationship of whole gut lavage fluid cytokines to relapse in inactive Crohn's disease. Fifty-four patients with inactive Crohn's disease were prospectively assessed. Inactivity was determined as a Crohn's disease activity index of <150 and whole gut lavage fluid immunoglobulin G <10 microg/ml. All patients underwent whole gut lavage with analysis of IL-1beta and IL-8. Follow up was for one year. Patients with elevated whole gut lavage fluid IL-1beta (P < 0.004) and IL-8 (P < 0.02) had greater chance of relapse. Young age, short disease duration, and fistulating disease also relapsed more frequently. Multiple regression identified IL-1beta as an independent variable. In conclusion, an elevated whole gut lavage fluid IL-1beta in inactive Crohn's disease identifies patients at high risk of relapse.

Topics: Adolescent; Adult; Age Factors; Aged; Biomarkers; Crohn Disease; Female; Humans; Interleukin-1; Interleukin-8; Intestinal Mucosa; Male; Middle Aged; Predictive Value of Tests; Prognosis; Prospective Studies; Recurrence; Regression Analysis; Risk Factors; Severity of Illness Index; Therapeutic Irrigation; Time Factors

Clinical differences between small- and large-bowel Crohn's disease have been demonstrated. Neutrophil migration and degranulation are important effector mechanisms in gut damage. Granulocyte elastase, a neutrophil-bound enzyme, interleukin 8 and 1beta can be detected in whole-gut lavage fluid. We aimed to assess differences between large- and small-bowel Crohn's disease.. A total of 167 patients with active inflammatory bowel disease (118 Crohn's disease, 49 ulcerative colitis) underwent whole-gut lavage with a polyethylene glycol electrolyte solution. Granulocyte elastase was assayed using an enzyme substrate reaction, IL-8 and IL-1beta by ELISA.. Twenty-seven of 36 patients with isolated colonic Crohn's disease had detectable granulocyte elastase (median 0.259 pKat/l, range < 0.039-2.742 microKat/l), whereas 3 of 15 with small-bowel involvement alone had detectable granulocyte elastase (median < 0.039 microKat/l, range < 0.039-0.266 microKat/l; P < 0.0001). Granulocyte elastase levels were significantly higher in patients with ileocolonic disease and post-ileocaecal resection compared with small-bowel disease alone. IL-8 (P< 0.0001) and IL-1beta (P < 0.04) levels differed between colonic and ileal distributions. No variations were seen in ulcerative colitis.. Neutrophil migration to the gut lumen in Crohn's disease is a feature of colonic disease irrespective of associated ileal lesions. This suggests that bacterial-derived chemo-attractants may play a role. High levels of IL-8 in colonic disease are consistent with this hypothesis.

Topics: Adult; Chemotaxis, Leukocyte; Colitis, Ulcerative; Crohn Disease; Female; Humans; Interleukin-1; Interleukin-8; Intestine, Large; Intestine, Small; Leukocyte Elastase; Male; Middle Aged; Neutrophils; Therapeutic Irrigation

Interleukin-8 (IL-8), a chemokine secreted by cells at injury sites, has recently been recognized as involved in the pathogenesis of Crohn's disease. However, the pathogenesis of enhanced spontaneous transcription of IL-8 by the bowel in patients with Crohn's disease is undefined. Although IL-8 is secreted primarily by neutrophils, macrophages, and endothelial and epithelial cells, we observed the involvement of mesenchymal cells in the inflammatory process. A smooth muscle cell line isolated from the ileum of a patient with Crohn's disease (CDISM) and maintained in culture exhibited spontaneous transcription and secretion of IL-8 when compared with intestinal smooth muscle cells obtained from a normal subject (NHISM). Furthermore, IL-8 transcription from CDISM cells was associated with remarkable spontaneous activation of the oxidant-sensitive transcription factor NF-kappaB, as assessed by transient transfection assays with an IL-8 promoter reporter construct, Western blot analysis, and electrophoretic mobility shift assays (EMSA). Finally, we report here that CDISM cells exhibit significantly altered redox balance. The antioxidant pyrrolidine dithiocarbamate (PDTC) restored the redox equilibrium by mechanisms that inhibit binding of NF-kappaB to its cognate site on the IL-8 promoter. These findings suggest that restoration of the redox balance could hold promise for therapeutic intervention in Crohn's disease.

Topics: Antioxidants; Cell Line; Crohn Disease; DNA-Binding Proteins; Genes, Reporter; Humans; I-kappa B Proteins; Interleukin-8; Intestinal Mucosa; Intestines; Muscle, Smooth; NF-kappa B; NF-KappaB Inhibitor alpha; Oxidation-Reduction; Promoter Regions, Genetic; Pyrrolidines; RNA, Messenger; Thiocarbamates; Transfection

This study aimed to determine if mucosal expression of the chemokines IL-8, RANTES and MCP-1 and the pro-inflammatory cytokines TNFalpha and IL-6 are elevated in patients with inflammatory bowel disease.. Intestinal mucosa samples were obtained at the time of surgical resection, n = 16 from each of the following groups: normal/control, CD and UC.. An homogenate was prepared of each tissue sample and cytokines measured by ELISA.. IL-8 was significantly increased in both disease groups compared to controls Similarly, RANTES levels were also significantly increased. MCP-1 levels were increased in both disease groups, this increase was statistically significant in the UC group only. TNFalpha and IL-6 were significantly increased in the CD group only.. Chemokines, together with key cytokines that promote their release are elevated in mucosal tissues from patients with IBD. It is likely that these chemokines play an important role in the perpetuation of tissue destructive inflammatory processes.

Topics: Chemokine CCL2; Chemokine CCL5; Chemokines; Colitis, Ulcerative; Colon; Crohn Disease; Cytokines; Enzyme-Linked Immunosorbent Assay; Humans; Interleukin-8; Intestinal Mucosa

Delayed neutrophil apoptosis is a feature of persistent acute inflammation. Neutrophil-mediated damage has been shown to be associated with the development of inflammatory bowel disease (IBD). Persistence of these cells both at the colonic site and circulation may further contribute to IBD. The aims of this study were to determine whether neutrophils isolated from IBD patients delay apoptosis and to investigate possible mechanisms involved in this delay. We studied 20 patients with IBD, 13 with Crohn's disease, and 7 with ulcerative colitis, all of whom were undergoing intestinal resection for symptomatic disease. Seventeen patients undergoing elective resection of colon cancer acted as operative controls. Systemic, mesenteric arterial, and mesenteric venous blood was harvested. Neutrophils isolated from patients with IBD showed decreased spontaneous apoptosis compared to cancer patients. Mesenteric venous serum of IBD patients contributed to this delay, which contained higher concentrations of interleukin-8 (IL-8). Pro-caspase 3 expression was also reduced in IBD neutrophils, which may contribute to decreased spontaneous and Fas antibody-induced apoptosis. Neutrophil apoptosis may be altered in Crohn's disease and ulcerative colitis through release of anti-apoptotic cytokines and altered caspase expression. The alterations in cell death mechanisms may lead to persistence of the inflammatory response associated with IBD.

Topics: Adolescent; Adult; Aged; Apoptosis; Case-Control Studies; Caspase 8; Caspase 9; Caspases; Colitis, Ulcerative; Crohn Disease; Enzyme Precursors; Female; Humans; Hydrocortisone; In Vitro Techniques; Interleukin-8; Male; Middle Aged; Neutrophils

Distinct Th1/Th2 patterns have been observed during the evolution of CD. The aim of this study was to compare neutrophil involvement and IL-8 mRNA and protein expression during early recurrent lesions and chronic phases of CD. Twenty-nine patients with CD having ileocolonic resection with anastomosis were studied. Biopsies were obtained during surgery from the non-inflamed ileal mucosa and from chronic ileal lesions. Endoscopic ileal biopsies were also taken from early recurrent ileal lesions occurring 3 months after surgery. Neutrophil counts were performed and mucosal IL-8 levels were evaluated by competitive reverse transcriptase-polymerase chain reaction and immunohistochemistry. Early recurrent ileal lesions were characterized by low neutrophil counts and IL-8 production at the mRNA and protein levels compared with the ileal chronic lesions. The main cellular sources of IL-8 in the early recurrent lesions were neutrophils, while in chronic lesions the majority of IL-8-stained cells were CD3+ T cells and macrophages. These results confirmed that the nature of the inflammatory infiltrate and the expression of cytokine profiles may differ between the acute and chronic phases of CD.

Topics: Adult; Base Sequence; Chronic Disease; Crohn Disease; DNA Primers; Female; Humans; Ileum; Interleukin-8; Intestinal Mucosa; Male; Neutrophils; RNA, Messenger; Time Factors

Interleukin-8 (IL-8) as an alpha-chemokine recruits and activates neutrophils, which are abundant in the intestinal lesions of ulcerative colitis (UC) and Crohn's disease (CD). Stromal cell-derived factor 1 (SDF1-alpha) is a new chemokine that is chemotactic to neutrophils. The aims of this study were to assess the relative expression of SDF1-alpha and IL-8 mRNA in different colonic regions and patients with inflammatory bowel disease with varied degrees of inflammation in the colon.. Colon biopsy samples were obtained from 19 patients with UC, 12 with CD, and 5 with irritable bowel syndrome (IBS) who underwent colonoscopy. Levels of IL-8 and SDF1-alpha mRNA expression were measured semiquantitatively by reverse-transcription and polymerase chain reaction amplification. The cytokine mRNA levels were corrected for glyceraldelyde-3-phosphate dehydrogenase mRNA expression.. IL-8 mRNA expression was significantly correlated with SDF1-alpha expression in normal biopsies from IBS patients (r = 0.58, p < 0.01). There was no significant difference in cytokine mRNA expression (IL-8 or SDF1-alpha) across different regions of the colon or rectum in uninflamed normal biopsies. The IL-8 mRNA expression ratios in UC (mean +/- SD, 1.03 +/- 0.52) and CD (0.90 +/- 0.38) patients were significantly higher than in IBS (0.52 +/- 0.17) (p < 0.01, p < 0.05, respectively). The SDF1-alpha mRNA expression ratio in UC (0.30 +/- 0.52) was higher than in both CD (0.21 +/- 0.10) and IBS patients (0.22 +/- 0.11) (p < 0.01, <0.05, respectively). A statistically significant correlation was found between the IL-8 mRNA expression and the colonic inflammation in UC patients (r = 0.44, p < 0.05) but not for SDF1-alpha expression in UC patients.. IL-8 but not SDF1-alpha mRNA expression was associated with inflammation in UC. This suggests that IL-8 may play a more important role in inflammatory bowel disease than does SDF1-alpha.

Topics: Adult; Biopsy; Case-Control Studies; Chemokine CXCL12; Chemokines, CXC; Colitis, Ulcerative; Colon; Colonic Diseases, Functional; Crohn Disease; Female; Glyceraldehyde-3-Phosphate Dehydrogenases; Humans; Interleukin-8; Male; Reverse Transcriptase Polymerase Chain Reaction; RNA, Messenger; Stromal Cells

Anecdotal reports suggest that smoking may be beneficial for patients with inflammatory bowel disease (IBD) as nicotine may act through inflammatory mediators within the colonic mucosa. Furthermore, there is increasing evidence that cytokines play a pathologic role in IBD. Our aim was to determine the effects of cigarette smoking on cytokine levels in the colonic mucosa of patients with and without IBD. Mucosal biopsies were obtained from 10 patients with Crohn's disease (CD), 10 with ulcerative colitis (UC), and 10 healthy controls. Five of 10 patients in each of the three groups were smokers and five were nonsmokers. Concentrations of interleukin (IL)-1beta, IL-2, IL-6, and IL-8 were determined using enzyme-linked immunosorbent assay (ELISA). Cytokine levels of smokers were compared with nonsmokers in each group and with controls. Results were analyzed using the Mann-Whitney test; significance was set at p<0.05. The concentration of IL-8 was significantly higher in healthy controls who smoke compared with nonsmokers and significantly reduced in smokers with CD compared with nonsmokers with CD. Moreover, concentrations of IL-1beta and IL-8 were significantly reduced in smokers with UC compared with nonsmokers with UC. Smokers had significantly elevated levels of IL-8 in the colonic mucosa. Smokers with IBD had a significant reduction in cytokine levels; specifically, IL-1beta and IL-8 for patients with UC and IL-8 for patients with CD. Further studies are warranted to determine if this reduction in cytokine levels is histologically and clinically significant.

Topics: Case-Control Studies; Colitis, Ulcerative; Colon; Crohn Disease; Enzyme-Linked Immunosorbent Assay; Humans; Interleukin-8; Interleukins; Intestinal Mucosa; Smoking

Neutrophil gelatinase-associated lipocalin (NGAL) is a newly described neutrophil lipocalin that may bind the proinflammatory bacterial tripeptide N-formylmethionyl-leucyl-phenylalanine. In situ hybridization and immunohistochemical studies have shown a strong NGAL expression in colonocytes and neutrophils in ulcerative colitis (UC). Because NGAL is highly protease resistant, it should be ideal for in vivo fecal and dialysate studies. Our aim was to investigate the potential of NGAL as a disease activity marker in UC and to compare it with IL-8 and TNF-alpha.. Twenty-three patients with UC, 14 with Crohn's disease (CD), 19 patients with acute infectious enterocolitis, and 20 healthy controls were included. The disease activity of UC and CD was scored semiquantitatively. Concentrations of NGAL, IL-8, and TNF-alpha were determined in rectal dialysis fluid, feces, and serum using sandwich enzyme-linked immunosorbent assays. The total protein concentration in feces and dialysate fluid was measured, and the amount of markers was expressed as ng/mg protein.. In healthy controls and non-IBD (irritable bowel disease) colitis, the median values for NGAL in feces were 183 ng/mg protein and 546 ng/mg protein (p < 0.01), respectively. When separating UC into clinical activity groups (remission, mild/moderate, and severe disease activity) the corresponding values of NGAL were 442 ng/mg (p > 0.05), 605 ng/mg (p < 0.02), and 3646 ng/mg (p < 0.001, compared with controls), respectively, and in quiescent colonic CD 368 ng/mg (p > 0.05) and in active stages 751 ng/mg (p < 0.01). NGAL levels in dialysis fluid listed in the same order were: 11 ng/mg for controls, 71 ng/mg (p > 0.05) for non-IBD colitis, 100 ng/mg (p < 0.02), 179 ng/mg (p < 0.01), and 2053 ng/mg (p < 0.001) for UC, and 14 ng/mg (p > 0.05) and 121 ng/mg (p < 0.02) for CD, respectively. Serum NGAL concentrations did not differ between UC and CD in quiescent versus active stages. A significant increase of NGAL in both feces and dialysate with increasing disease activity of UC was found (p = 0.02 and p = 0.003, respectively).. The NGAL content in rectal dialysate and particularly in feces seems to be a reliable marker for severe disease activity in UC, whereas serum NGAL concentrations do not reflect disease activity.

Topics: Acute-Phase Proteins; Adult; Aged; Biomarkers; Carrier Proteins; Colitis, Ulcerative; Crohn Disease; Enzyme-Linked Immunosorbent Assay; Feces; Female; Humans; Interleukin-8; Lipocalin-2; Lipocalins; Male; Middle Aged; Neutrophils; Oncogene Proteins; Proto-Oncogene Proteins; Rectum; Tumor Necrosis Factor-alpha

To elucidate the possible role of proinflammatory cytokines in inflammatory bowel disease, the expression and localization of interleukin (IL) -6 and IL-8 mRNAs were examined in colonic biopsy specimens obtained from 10 patients with active ulcerative colitis (UC), 5 with inactive UC, 6 with Crohn's disease (CD), and 5 normal controls. In situ hybridization with digoxigenin-labeled probes and immunohistochemistry for both cytokines were performed. The IL-6 mRNA expression was enhanced in the inflamed mucosa in 4 of 6 CD patients, while that of UC patients stayed at baseline. In contrast, IL-8 mRNA expression was apparently augmented (P = 0.044) in 7 of 10 active UC and 3 of 6 CD patients (NS). The cell count positive for IL-8 mRNA per unit area was definitely increased in moderate/severe UC when compared to mild UC (53.1 +/- 14.4/mm2 vs 9.0 +/- 5.1/mm2, P = 0.028) according to the degree of inflammation. IL-6 mRNA positive cells in CD were preferentially located in deeper lamina propria than IL-8 mRNA positive cells in UC. Interestingly, IL-8 mRNA was expressed in the mucosal epithelial cells in one UC patient. The patients treated by corticosteroids tended to show suppressed expression of each mRNA, except one patient with intractable UC. Our data suggest enhanced expression of mucosal IL-6 mRNA in CD and of IL-8 mRNA in UC by infiltrating mononuclear cells, indicating the distinct participation of each cytokine in the pathogenesis of UC and CD. Moreover, intestinal epithelial cells in UC occasionally exhibit IL-8 mRNA.

Topics: Colitis, Ulcerative; Crohn Disease; DNA Primers; DNA, Complementary; Gene Expression Regulation; Humans; Immunohistochemistry; In Situ Hybridization; Interleukin-6; Interleukin-8; Intestinal Mucosa; RNA, Messenger; Up-Regulation

Crohn's disease (CD) lesions are characterized by a marked neutrophilic infiltrate associated with enhanced mucosal IL-8, contrasting with low serum IL-8 levels. The aim of this study was to investigate the effects of circulating GROalpha and IL-8 on neutrophil priming and migration. The expression of surface molecules involved in rolling (CD62L, CD15) and firm adhesion (Mac-1 and LFA-1) to endothelial cells was assessed by flow cytometry, while the chemotactic response of PMN to IL-8 and to fMLP was investigated in a Boyden chamber assay. In addition, IL-8 and GROalpha levels were determined by ELISA in plasma samples and in culture supernatants of purified polymorphonuclear neutrophils (PMN) and peripheral blood mononuclear cells (PBMC) from patients with CD and healthy blood donors. This study revealed an upregulation of CD11b (Mac-1) membrane expression on circulating PMN from patients with CD, as assessed by the mean fluorescence intensity which reflects antigen density. Furthermore, an enhanced chemotactic response towards both fMLP and IL-8 of PMN from CD patients was observed. Despite often undetectable levels of circulating IL-8, all plasma samples were positive for GROalpha, with a significant increase in CD patients when compared to donors. In vitro, equivalent concentrations of GROalpha were able to increase the IL-8 driven chemotaxis of PMN. In conclusion, blood PMN from patients with CD showed an enhanced capacity to be recruited into inflammed intestinal mucosa, which could be due to an increased expression of CD11b (Mac-1) as well as an increased chemotactic response toward fMLP or IL-8. This priming effect of PMN in CD may partly occur through elevated circulating GROalpha levels.

Topics: Case-Control Studies; Cell Adhesion; Cell Movement; Chemokine CXCL1; Chemokines, CXC; Chemotactic Factors; Chemotaxis, Leukocyte; Crohn Disease; Growth Substances; Humans; Immunity, Mucosal; In Vitro Techniques; Intercellular Signaling Peptides and Proteins; Interleukin-8; L-Selectin; Lewis X Antigen; Lymphocyte Function-Associated Antigen-1; Macrophage-1 Antigen; N-Formylmethionine Leucyl-Phenylalanine; Neutrophils

Interleukin-8 (IL-8) and nitric oxide (NO) may be important mediators in the pathogenesis of chronic idiopathic inflammatory bowel disease (CIIBD), but their roles in disease activity in ulcerative colitis (UC) and Crohn's disease (CD) are uncertain. The aim of this study was to measure mRNA for IL-8 and inducible NO synthase (iNOS) in small mucosal biopsies from untreated patients at first presentation and to relate these measurements to the histological levels of polymorph infiltration graded on a ten-point scale. For this purpose, a sensitive enzyme-linked oligonucleotide chemiluminescent assay (ELOCA) was developed to quantitate reverse transcription-polymerase chain reaction (RT-PCR) products amplified from RNA from paired biopsy samples. The levels of IL-8 and iNOS mRNAs were calculated as ratios of the RT-PCR products to glyceraldehyde-3-phosphate dehydrogenase (GAPDH) RT-PCR product. In UC patients, median values of IL-8/GAPDH and iNOS/GAPDH were significantly elevated compared with controls and CD. However, in both UC and CD, the IL-8/GAPDH and iNOS/GAPDH ratios correlated significantly with polymorph infiltration. ELOCA enabled quantitation of multiple mRNAs in small mucosal biopsies from untreated patients with CIIBD and supported a role for IL-8 and iNOS in acute inflammation in both UC and CD.

Topics: Adult; Aged; Cell Movement; Colitis, Ulcerative; Crohn Disease; Female; Humans; Interleukin-8; Intestinal Mucosa; Luminescent Measurements; Male; Middle Aged; Neutrophils; Nitric Oxide Synthase; Polymerase Chain Reaction; RNA, Messenger

The aim of the study was to assess in vitro the production of interleukin 8 in Crohn's disease and ulcerative colitis.. Interleukin 8 concentrations (measured by ELISA) were evaluated in the culture supernatants of: a) peripheral blood mononuclear cells from 13 patients with Crohn's disease, 7 patients with ulcerative colitis and 7 controls, b) organ cultures of inflamed (22 Crohn's disease, 15 ulcerative colitis) and uninflamed (21 Crohn's disease, 9 ulcerative colitis, 15 controls) intestinal mucosal biopsies.. In patients with Crohn's disease and ulcerative colitis, the production of interleukin 8 by peripheral blood mononuclear cells and inflamed mucosa was higher than in controls (P < 0.01) without statistical difference between Crohn's disease and ulcerative colitis. Interleukin 8 production by normal mucosa was not different between the 3 groups. Interleukin 8 concentrations in the supernatants of organ culture were positively correlated to an endoscopical and a histological inflammatory index as well as to tumor necrosis factor, interleukin 1 and 6 concentrations.. These results support the notion that interleukin 8 plays an important role in the pathogenesis of inflammatory bowel disease.

Topics: Adult; Biopsy; Cells, Cultured; Colitis, Ulcerative; Crohn Disease; Female; Humans; Inflammation Mediators; Interleukin-8; Intestinal Mucosa; Leukocytes, Mononuclear; Male; Middle Aged; Organ Culture Techniques; Tumor Necrosis Factor-alpha

Inflammatory cytokines, including tumour necrosis factor-alpha (TNF-alpha) and interleukin (IL)-1 beta, have been implicated as primary mediators of intestinal inflammation in inflammatory bowel disease.. To investigate the in vitro effects of oxpentifylline (pentoxifylline; PTX; a phosphodiesterase inhibitor) on inflammatory cytokine production (1) by peripheral mononuclear cells (PBMCs) and (2) by inflamed intestinal mucosa cultures from patients with Crohn's disease and patients with ulcerative colitis.. PBMCs and mucosal biopsy specimens were cultured for 24 hours in the absence or presence of PTX (up to 100 micrograms/ml), and the secretion of TNF-alpha, IL-1 beta, IL-6, and IL-8 determined by enzyme linked immunosorbent assays (ELISAs).. PTX inhibited the release of TNF-alpha by PBMCs from patients with inflammatory bowel disease and the secretion of TNF-alpha and IL-1 beta by organ cultures of inflamed mucosa from the same patients. Secretion of TNF-alpha by PBMCs was inhibited by about 50% at a PTX concentration of 25 micrograms/ml (IC50). PTX was equally potent in cultures from controls, patients with Crohn's disease, and those with ulcerative colitis. The concentrations of IL-6 and IL-8 were not significantly modified in PBMCs, but IL-6 increased slightly in organ culture supernatants.. PTX or more potent related compounds may represent a new family of cytokine inhibitors, potentially interesting for treatment of inflammatory bowel disease.

Topics: Adult; Colitis, Ulcerative; Colon; Crohn Disease; Culture Techniques; Cytokines; Female; Humans; Inflammatory Bowel Diseases; Interleukin-1; Interleukin-6; Interleukin-8; Intestinal Mucosa; Leukocytes, Mononuclear; Male; Middle Aged; Pentoxifylline; Phosphodiesterase Inhibitors; Tumor Necrosis Factor-alpha

Epithelial cell-derived neutrophil-activating protein-78 (ENA-78) is a neutrophil-directed C-X-C chemokine. We report that Caco-2 and T84 human intestinal epithelial cells produce ENA-78 after stimulation by interleukin (IL)-1 beta or tumor necrosis factor-alpha. Caco-2 cells show increased IL-8 production at 4-12 h and increased ENA-78 production at 8-24 h after cytokine stimulation. Immunohistochemical studies in normal human colon and in ulcerative colitis demonstrate ENA-78 immunoreactivity principally associated with crypt epithelial cells. Furthermore, human colonic tissues from patients with ulcerative colitis show elevated levels of ENA-78 mRNA (24-fold increase, P < 0.01) and protein (4-fold increase, P < 0.05) compared with normal controls. Thus ENA-78 is produced in normal colon and in ulcerative colitis and is predominantly of enterocyte origin. The kinetics of ENA-78 induction in human colon epithelial cell lines are delayed and prolonged compared with IL-8. We propose that ENA-78 and IL-8 serve complementary and sequential roles in neutrophil recruitment in ulcerative colitis. ENA-78 as an enterocyte-derived, neutrophil-activating chemokine may be especially important in neutrophil recruitment from the lamina propria into the epithelial layer.

Topics: Cell Line; Chemokine CXCL5; Chemokines, CXC; Colitis, Ulcerative; Colon; Colonic Neoplasms; Crohn Disease; DNA Primers; Enzyme-Linked Immunosorbent Assay; Humans; Immunohistochemistry; Interleukin-1; Interleukin-8; Intestinal Mucosa; Polymerase Chain Reaction; Protein Biosynthesis; RNA, Messenger; Signal Transduction; Transcription, Genetic; Tumor Cells, Cultured

Interleukin-8 (IL-8) is an important cytokine for recruitment and activation of polymorphonuclear neutrophils (PMNs), cells that are abundant in the intestinal lesions of ulcerative colitis (UC) and Crohn's disease (CD). The present investigation was conducted to evaluate intestinal IL-8 concentration and IL-8 gene expression in parallel in inflammatory bowel disease (IBD) patients and a non-inflammatory control group.. The intestinal concentration of IL-8 was measured with a sandwich enzyme-linked immunosorbent assay (ELISA) technique (detection limit, 17.4 pg/mg protein), and relative quantitation of IL-8 mRNA transcript levels was done with a reverse transcription polymerase chain reaction (RT-PCR)-based method. Biopsy specimens from 66 humans who underwent colonoscopy--28 with UC, 18 with CD and colonic involvement, and 20 non-inflammatory disease-specific controls who subsequently were found to fulfill the diagnostic criteria for irritable bowel syndrome (IBS)--were included. None had received glucocorticoids within 3 months.. Using a one-tailed variance analysis, a significant concordance between increasing IL-8 protein concentrations and disease activity was found both in UC and CD (P < 0.001), and only trace amounts were detected in IBS biopsy specimens. No differences were found between the two groups of UC and CD patients (P > 0.05), and no differences were found between quiescent IBD and IBS (P > 0.05). However, the PCR method showed IL-8 mRNA in 8 of 18 CD patients (44.4%; 95% confidence limits, 21.5-69.2%) and 7 of 28 UC patients (25.9%; 95% confidence limits, 11.1-46.3%), as compared with 0 of 20 IBS (P < 0.005). Increased IL-8 mRNA levels were found only in active CD, which was not the case in UC. No correlation was found between intestinal IL-8 ELISA and IL-8-mRNA levels (r = 0.24, P > 0.05).. The observed correlation between disease activity and expression of the IL-8 gene in active CD colitis but not in UC and the increased IL-8 protein concentrations in affected intestinal segments of IBD as compared with the non-inflamed IBS indicate a possible transient IL-8 gene expression or altered mRNA stability in UC and CD, as is well known for other cytokines, such as IL-2. If so, it may form the basis of new therapeutic regimens for IBD like IL-10.

Topics: Adult; Case-Control Studies; Colitis, Ulcerative; Colon; Crohn Disease; Enzyme-Linked Immunosorbent Assay; Female; Gene Expression; Humans; Interleukin-8; Intestinal Mucosa; Male; Middle Aged; Polymerase Chain Reaction; RNA, Messenger

To test whether there is a difference in the expression of interleukin 8 (IL8) between Crohn's disease and ulcerative colitis and to determine the main site of its synthesis this study analysed IL8 in mucosal biopsy specimens of patients with Crohn's disease and ulcerative colitis by enzyme linked immunosorbent assay (ELISA) and by in situ hybridisation. IL8 was measured by ELISA in 38 normal control patients, eight inflammatory control patients, 55 Crohn's disease biopsy specimens (26 patients), and 67 ulcerative colitis biopsy specimens (35 patients). IL8 mRNA was determined in samples by in situ hybridisation using a specific IL8 RNA probe. IL8 protein was significantly increased in macroscopically inflamed specimens of Crohn's disease (median 118 pg/specimen, p < 0.0001), ulcerative colitis (median 140 pg/specimen, p < 0.001), and inflammatory controls (median 30 pg/specimen, p = 0.010) compared with normal controls (median 4 pg/specimen). IL8 was also increased in uninflamed specimens of Crohn's disease (median 46 pg/specimen, p < 0.001) but not of ulcerative colitis patients (median 9 pg/specimen, p = 0.3). IL8 protein in the mucosa correlated significantly with macroscopic inflammation in Crohn's disease (r = 0.47, p < 0.001) and in ulcerative colitis (r = 0.60, p < 0.001). IL8 mRNA was detected by in situ hybridisation in 31 of 55 biopsy specimens (56%) of Crohn's disease patients, in 38 of 67 specimens of ulcerative colitis patients (57%), in five of eight inflammatory controls (63%) and in five of 38 normal controls (13%). Mucosal IL8 mRNA expression correlated with mucosal IL8 protein (r = 0.46, p < 0.001). IL8 mRNA was only detected in inflammatory cells of the interstitium but not in mucosal epithelial cells. IL8 is produced mainly in the lamina propria of the colon in inflammatory bowel disease and correlates with mucosal inflammation.

Topics: Adolescent; Adult; Aged; Biopsy; Case-Control Studies; Colitis, Ulcerative; Colon; Crohn Disease; Enzyme-Linked Immunosorbent Assay; Female; Gene Expression; Humans; In Situ Hybridization; Interleukin-8; Intestinal Mucosa; Male; Middle Aged; RNA, Messenger

Epithelia from several sites exhibit inducible secretion of interleukin 8 (IL-8). This study aimed to characterise secretion of IL-8 by colonic epithelial cells in vitro. Colonic crypt cells were isolated enzymatically from resected colon and the IL-8 content of culture supernates was measured by ELISA. The rate of secretion of IL-8 accelerated and levels of IL-8 transcripts increased appreciably during culture. Exposure to tumour necrosis factor alpha (TNF alpha) failed to increase secretion further. Secretion was not induced by the enzymatic digestion or by serum used in the culture medium but was significantly inhibited by butyrate, by a mean of 23%. Control experiments indicated that colonic crypt cells were the likely source. The secretion of IL-8 over 24 hours by cells from uninflamed mucosa of patients with ulcerative colitis or Crohn's disease was more than twofold that from normal cells, while that from cancer bearing colons was normal. TNF alpha (10 mM) significantly suppressed IL-8 secretion only in the ulcerative colitis group and the change was different to those in the normal (p = 0.007) and Crohn's disease groups (p = 0.012). Cells from inflamed areas secreted more IL-8 than those from autologous uninflamed areas (p = 0.009) but responses to modulating factors were no different. The induction of IL-8 secretion by colonic crypt cells in vitro is probably a response to injury associated with isolation and culture. It is suppressed by butyrate and increased in inflammatory bowel disease independently of the presence of mucosal inflammation. Whether epithelial derived IL-8 plays a part in the pathogenesis of inflammatory bowel disease is not yet clear.

Topics: Adolescent; Adult; Aged; Aged, 80 and over; Blotting, Northern; Butyrates; Cell Survival; Cells, Cultured; Colitis, Ulcerative; Colon; Crohn Disease; Female; Humans; Interleukin-8; Intestinal Mucosa; Male; Middle Aged; Tumor Necrosis Factor-alpha

Increasing evidence points to a pathologic role for cytokines in Crohn's colitis. Levels of cytokines are increased in diseased segments of colon in Crohn's colitis, but no one has studied the concentration of cytokines in clinically and histologically nondiseased segments.. Mucosal biopsies were obtained from 7 patients with active segmental Crohn's colitis and from 7 controls without inflammatory bowel disease. The concentration of Interleukin (IL)-1 beta, IL-2, IL-6, and IL-8 in patients and controls were determined using enzyme linked immunosorbent assay and compared. Histologic sections were also performed to confirm diseased and nondiseased segments of colon.. The concentrations of IL-1 beta, IL-6, and IL-8 were significantly higher in the involved segments of colon (10.3 +/- 4.1, 3.7 +/- 1.0, 34.4 +/- 6.9 picograms [pg] per mg) when compared to controls (1.8 +/- 0.5, 1.1 +/- 0.5, 5.3 +/- 1.0 pg/mg). The concentrations of IL-1 beta, IL-2, and IL-8 (8.5 +/- 2.9, 5.3 +/- 1.2, 26.3 +/- 8.8 pg/mg) in normal appearing segments of colon of patients with Crohn's colitis were also significantly higher than in controls, whose IL-2 level was 2.0 +/- 0.5 pg/mg. IL-1 beta and IL-8 were significantly more concentrated in both the involved and uninvolved colonic segments of patients with Crohn's colitis compared to controls. IL-2 and IL-6 were also more concentrated in Crohn's patients than in controls, but not significantly. The differences in interleukin concentrations between involved and uninvolved segments of colon in patients with segmental Crohn's colitis were not significant.. Although Crohn's colitis is often a segmental disease, concentrations of IL-1 beta and IL-8 are increased throughout the entire colon. These observations reinforce the hypothesis that Crohn's colitis involves the whole colon even when this is not apparent clinically or histologically.

Topics: Adult; Aged; Colon; Crohn Disease; Female; Humans; Interleukin-1; Interleukin-2; Interleukin-6; Interleukin-8; Interleukins; Intestinal Mucosa; Male; Middle Aged

Tissue and plasma concentrations of several cytokines are increased in patients with inflammatory bowel disease (IBD). Platelets play an important role in inflammation and circulate in an activated state in patients with IBD. This study assesses the expression of IL-8 and IL-1 receptors on the surface of platelets from patients with IBD using phycoerythrin (PE)-labelled recombinant human rhIL-1 beta and rhIL-8 and flow cytometry. The percentage IL-1R expressing platelets (median and interquartile range IQR) in the IBD group was 8.7% (5.5-18.2) compared to 4.2% (2.3-6.1) in controls (P = 0.02). The percentage IL-8R expressing platelets in the IBD group was 22.5% (16.5-27.9) and 9.2% (4.3-9.6) in controls (P < 0.001). Furthermore, platelet IL-1R expression in patients with IBD was inversely related to the total daily dose of steroids (r = 0.71, P < 0.01 linear regression analysis). Finally, platelet rich plasma from healthy controls was stimulated with rhIL-1 beta and rhIL-8 and assessed for activation dependent expression of platelet aGPIIb/IIIa and CD62 (p-selectin, GMP-140). IL-1 beta and IL-8 in vitro significantly and specifically activated the platelets. The surface membrane of platelets is able to express functional IL-1R and IL-8R, the expression of which is significantly increased in IBD. Interleukin-1 beta and IL-8 modulate platelet activation in vitro indicating a target role for platelet function in inflammation.

Topics: Adolescent; Adult; Blood Platelets; Colitis, Ulcerative; Crohn Disease; Female; Humans; Interleukin-1; Interleukin-8; Male; Middle Aged; P-Selectin; Platelet Activation; Platelet Membrane Glycoproteins; Receptors, Interleukin; Receptors, Interleukin-1; Receptors, Interleukin-8A

IL-8 is generating increasing interest as a powerful neutrophil chemoattractant and activator. To elucidate the mechanisms of neutrophil infiltration in inflammatory bowel disease, we examined 33 patients with ulcerative colitis (UC), 18 with Crohn's disease (CD), eight with some other type of colitis, and 18 normal control subjects for measurement of IL-8 in homogenates of colonic biopsy specimens. The affected colonic mucosa was found to contain significantly more IL-8 in patients with active inflammatory bowel disease than in patients with inactive disease (UC, P < 0.001; CD, P < 0.001), in patients with other types of colitis (UC, P < 0.05; CD, P < 0.01), or in normal control subjects (UC, P < 0.001; CD, P < 0.001). Colonic IL-8 levels correlated significantly with the macroscopic grade of local inflammation, especially in patients with UC (P < 0.001). Colonic IL-8 levels also correlated well with the neutrophil numbers in mucosal tissue (UC, r = 0.950, P < 0.001; CD, r = 0.940, P < 0.001), and with colonic IL-1 beta (r = 0.911, P < 0.001) and tumour necrosis factor-alpha (TNF-alpha) levels (r = 0.604, P < 0.001) in patients with these two conditions. These data suggest a potential role for IL-8 and its regulatory cytokines IL-1 and TNF-alpha in mediating neutrophil infiltration of the gut wall in inflammatory bowel disease.

Topics: Adolescent; Adult; Aged; Cell Count; Chemotactic Factors; Colitis, Ulcerative; Crohn Disease; Female; Humans; Interleukin-1; Interleukin-8; Male; Middle Aged; Neutrophils; Tumor Necrosis Factor-alpha

Interleukin-8 (IL-8) is a potent cytokine for recruitment and activation of neutrophils. To visualize its distribution in the intestinal mucosa and to understand better its possible role in the induction and promotion of inflammatory bowel disease, expression of the IL-8 gene was analyzed in resected bowel segments of 14 patients with active Crohn's disease or ulcerative colitis. In situ hybridization with IL-8 anti-sense RNA probes revealed strong and specific signals in the histologically affected mucosa. The number of cells expressing IL-8 gene correlated with the histological grade of active inflammation. In accordance with the characteristic histological signs of active disease, IL-8-expressing cells were diffusely distributed over the entire affected mucosa in patients with ulcerative colitis, whereas in patients with Crohn's disease, IL-8-expressing cells showed a focal distribution pattern. Cells expressing IL-8 were mainly located at the base of ulcers, in inflammatory exudates on mucosal surfaces, in crypt abscesses, and at the border of fistulae. Analysis of semi-serial sections pointed to macrophages, neutrophils, and epithelial cells as possible sources of this cytokine in active inflammatory bowel disease. We consistently failed to detect IL-8 messenger RNA in the mucosa of uninvolved bowel segments and in normal-appearing control mucosa of patients with colon cancer. In contrast, tissue specimens from two patients with acute appendicitis displayed IL-8-expressing cells in the mucosa. These results support the notion that IL-8 plays and important but nonspecific role in the pathogenesis of inflammatory bowel disease and that the production of IL-8 messenger RNA is restricted to areas with histological signs of inflammatory activity and mucosal destruction.

Topics: Adult; Aged; Colitis, Ulcerative; Crohn Disease; Female; Gene Expression Regulation; Humans; In Situ Hybridization; Interleukin-8; Intestinal Mucosa; Male; Middle Aged; RNA Probes; Severity of Illness Index

We considered the role of two neutrophil chemotactic agents (interleukin-8 and leukotriene B4) and of myeloperoxidase (a neutrophil-associated enzyme) in the pathologic condition of Crohn's disease (CD). Serial biopsy samples were taken at different sites in the colon, washed in 0.02 M phosphate-saline buffer, homogenized, and then sonicated. Interleukin-8 levels were significantly increased throughout the colonic mucosa (> 300 pg/mg protein) in patients with CD compared with control groups (< 40 pg/mg protein) (p < or = 0.01). A two- to six-fold increase in leukotriene B4 was also found in CD, whereas mucosal levels of myeloperoxidase were unchanged compared with control subjects. This study demonstrates that interleukin-8 and leukotriene B4 may have an immunologic role in the pathologic condition of CD.

Topics: Adult; Aged; Chromatography, High Pressure Liquid; Colon; Crohn Disease; Humans; Interleukin-8; Intestinal Mucosa; Leukotriene B4; Middle Aged; Peroxidase; Radioimmunoassay

1. We studied neutrophil-activating peptide-1/interleukin-8 in inflammatory bowel disease. 2. Mucosal levels of neutrophil-activating peptide-1/interleukin-8 were significantly higher in patients with active ulcerative colitis [median 74.5 (range 17.7-450.8) pg/mg] than in patients with active Crohn's disease [10.4 (4-46.9) pg/mg; P less than 0.002] or in normal control subjects [10.4 (4-16.6) pg/mg; P less than 0.002]. 3. Circulating neutrophil-activating peptide-1/interleukin-8 was generally undetectable but there were higher levels of anti-neutrophil-activating peptide-1/interleukin-8 antibodies in patients with active ulcerative colitis [62.9 (3.4-239) ng/ml] than in patients with active Crohn's disease [5.9 (2.1-18.10) ng/ml; P less than 0.001] or in control subjects [6.1 (3.2-15.8) ng/ml; P less than 0.001]. 4. Neutrophil-activating peptide-1/interleukin-8 may be of specific functional importance in mediating inflammation in ulcerative colitis.

Topics: Antibodies; Colitis, Ulcerative; Crohn Disease; Humans; Interleukin-8; Intestinal Mucosa