2-4-dinitrofluorobenzene-sulfonic-acid and Inflammation

Bifidobacterium breve was the first bacteria isolated in the feces of healthy infants and is a dominant species in the guts of breast-fed infants. Some strains of B. breve have been shown to be effective at relieving intestinal inflammation, but the modes of action have yet to be elucidated. In this study, we investigated the mechanisms of action of B. breve CBT BR3 isolated from South Korean infant feces in relieving colitis in vitro and in vivo.. Colitis was induced in mice with dextran sodium sulfate (DSS) and dinitrobenzene sulfonic acid (DNBS). Quantitative reverse-transcription polymerase chain reaction, in vitro FITC-dextran flux permeability assay, and aryl hydrocarbon receptor (AhR) luciferase assay are performed using Caco-2 cells and HT29-Lucia™ AhR cells.. B. breve CBT BR3 was orally administered. B. breve CBT BR3 improved colitis symptoms in both DSS- and DNBS-induced colitis models. B. breve CBT BR3 increased the number of goblet cells per crypt. B. breve increased the mRNA expressions of Notch, Spdef, Muc5, and Il22. The mRNA expressions of Occludin, which encodes a membrane tight-junction protein, and Foxo3, which encodes a protein related to butyrate metabolism, were also increased in the DSS- and DNBS-induced colitis models. B. breve CBT BR3 protected inflammation-induced epithelial cell permeability and improved goblet cell function by inducing aryl hydrocarbon receptor in vitro.. These results indicate that B. breve CBT BR3 is effective at relieving intestinal inflammation by augmenting goblet cell regeneration.

Topics: Animals; Bifidobacterium breve; Caco-2 Cells; Colitis; Dextran Sulfate; Disease Models, Animal; Goblet Cells; Humans; Inflammation; Intestinal Mucosa; Mice; Mice, Inbred C57BL; Receptors, Aryl Hydrocarbon; Regeneration; RNA, Messenger

Gut microbiota are involved in the onset and development of chronic intestinal inflammation. The recently described endocannabinoidome (eCBome), a diverse and complex system of bioactive lipid mediators, has been reported to play a role in various physio-pathological processes such as inflammation, immune responses and energy metabolism. The eCBome and the gut microbiome (miBIome) are closely linked and form the eCBome - miBIome axis, which may be of special relevance to colitis.. Colitis was induced in conventionally raised (CR), antibiotic-treated (ABX) and germ-free (GF) mice with dinitrobenzene sulfonic acid (DNBS). Inflammation was assessed by Disease Activity Index (DAI) score, body weight change, colon weight-length ratio, myeloperoxidase (MPO) activity and cytokine gene expression. Colonic eCBome lipid mediator concentrations were measured by HPLC-MS /MS.. GF mice showed increased levels of anti-inflammatory eCBome lipids (LEA, OEA, DHEA and 13- HODE-EA) in the healthy state and higher MPO activity. DNBS elicited reduced inflammation in GF mice, having lower colon weight/length ratios and lower expression levels of Il1b, Il6, Tnfa and neutrophil markers compared to one or both of the other DNBS-treated groups. Il10 expression was also lower and the levels of several N-acyl ethanolamines and 13-HODE-EA levels were higher in DNBS-treated GF mice than in CR and ABX mice. The levels of these eCBome lipids negatively correlated with measures of colitis and inflammation.. These results suggest that the depletion of the gut microbiota and subsequent differential development of the gut immune system in GF mice is followed by a compensatory effect on eCBome lipid mediators, which may explain, in part, the observed lower susceptibility of GF mice to develop DNBS-induced colitis.

Topics: Animals; Colitis; Dinitrobenzenes; Inflammation; Lipids; Mice

Similar to canine inflammatory enteropathy, inflammatory bowel disease (IBD) is a chronic idiopathic condition characterized by remission periods and recurrent flares in which diarrhea, visceral pain, rectal bleeding/bloody stools, and weight loss are the main clinical symptoms. Intestinal barrier function alterations often persist in the remission phase of the disease without ongoing inflammatory processes. However, current therapies include mainly anti-inflammatory compounds that fail to promote functional symptoms-free disease remission, urging new drug discoveries to handle patients during this step of the disease. ALIAmides (ALIA, autacoid local injury antagonism) are bioactive fatty acid amides that recently gained attention because of their involvement in the control of inflammatory response, prompting the use of these molecules as plausible therapeutic strategies in the treatment of several chronic inflammatory conditions. N-palmitoyl-D-glucosamine (PGA), an under-researched ALIAmide, resulted in being safe and effective in preclinical models of inflammation and pain, suggesting its potential engagement in the treatment of IBD. In our study, we demonstrated that micronized PGA significantly and dose-dependently reduces colitis severity, improves intestinal mucosa integrity by increasing the tight junction proteins expression, and downregulates the TLR-4/NLRP3/iNOS pathway via PPAR-α receptors signaling in DNBS-treated mice. The possibility of clinically exploiting micronized PGA as support for the treatment and prevention of inflammation-related changes in IBD patients would represent an innovative, effective, and safe strategy.

Topics: Animals; Colitis; Dinitrofluorobenzene; Dogs; Glucosamine; Inflammation; Inflammatory Bowel Diseases; Mice; NLR Family, Pyrin Domain-Containing 3 Protein; PPAR alpha; Toll-Like Receptor 4

Management of abdominal pain, a common symptom of IBDs and IBS, is still a clinical problem. Extra virgin olive oil (EVOO), a main component of the Mediterranean diet, shows positive effects on chronic inflammation in IBDs. In this study, the effect of the oral administration of EVOO (3 mL) and two olive milling by-products, DPA (300 mg kg

Topics: Abdominal Pain; Animals; Colitis; Colon; Diet, Mediterranean; Dinitrofluorobenzene; Disease Models, Animal; Functional Food; Gastrointestinal Diseases; Inflammation; Male; Olea; Olive Oil; Phenols; Plant Oils; Rats; Rats, Sprague-Dawley

Guanosine, a guanine-based purine, is an extracellular signaling molecule exerting anti-inflammatory and antioxidative effects in several in vivo and in vitro injury models. We aimed to investigate its protective effects on 2, 4-dinitrobenzene sulfonic acid (DNBS)-induced colitis in rat.. Rats were divided into five groups and colitis was induced by intracolonic instillation of DNBS (15 mg/rat). Guanosine (4 or 8 mg/kg) was administered for 6 days i.p. starting the day of the colitis induction. Body weight loss, stool consistency, colon weight/length, histological analysis, myeloperoxidase activity (MPO) and pro-inflammatory cytokine levels were assessed. Immunoblotting of nuclear factor-κB (NF-κB) p65 protein levels and detection of oxidative and nitrosative stress markers were also performed.. Guanosine, in a dose-dependent manner, significantly ameliorated the severity of DNBS-induced colitis, reducing body weight loss and diarrhea incidence, preventing the DNBS-induced macroscopic and microscopic damage to the colonic mucosa, and the MPO increase. Guanosine treatment also lowered interleukin-1β, interleukin-6, and tumor necrosis factor-α mRNA levels. Importantly, guanosine in DNBS rats down-regulated the expression of NF-κB p65 and the levels of reactive oxygen species and nitrite.. In conclusion, guanosine exerts beneficial effects in DNBS-induced colitis in rats, through modulation of colonic inflammation, downregulating of NFκB-mediated signaling.

Topics: Animals; Anti-Inflammatory Agents; Antioxidants; Colitis; Colon; Cytokines; Dinitrofluorobenzene; Guanosine; Inflammation; Interleukin-1beta; Interleukin-6; Intestinal Mucosa; NF-kappa B; Rats; Rats, Wistar; Reactive Oxygen Species; Tumor Necrosis Factor-alpha

The gut barrier plays an important role in human health. When barrier function is impaired, altered permeability and barrier dysfunction can occur, leading to inflammatory bowel diseases, irritable bowel syndrome or obesity. Several bacteria, including pathogens and commensals, have been found to directly or indirectly modulate intestinal barrier function. The use of probiotic strains could be an important landmark in the management of gut dysfunction with a clear impact on the general population. Previously, we found that Lactobacillus rhamnosus CNCM I-3690 can protect intestinal barrier functions in mice inflammation model. Here, we investigated its mechanism of action. Our results show that CNCM I-3690 can (i) physically maintain modulated goblet cells and the mucus layer and (ii) counteract changes in local and systemic lymphocytes. Furthermore, mice colonic transcriptome analysis revealed that CNCM I-3690 enhances the expression of genes related to healthy gut permeability: motility and absorption, cell proliferation; and protective functions by inhibiting endogenous proteases. Finally, SpaFED pili are clearly important effectors since an L. rhamnosus ΔspaF mutant failed to provide the same benefits as the wild type strain. Taken together, our data suggest that CNCM I-3690 restores impaired intestinal barrier functions via anti-inflammatory and cytoprotective responses.

Topics: Animals; Caco-2 Cells; Colon; Cytoprotection; Dinitrofluorobenzene; Gene Expression Profiling; Goblet Cells; HEK293 Cells; HT29 Cells; Humans; Inflammation; Intestinal Mucosa; Intestines; Lacticaseibacillus rhamnosus; Mice; Mucus; Mutation; Permeability; Probiotics; Protective Agents

Owing to the recent progress in regenerative medicine technology, clinical trials that harnessed the regeneration and immune modulation potentiality of stem cells for treating IBD have shown promising results. We investigated the feasibility and utility of intraluminal endoscopic transplantation of rat MSC sheets in murine models of experimental colitis for targeted delivery of stem cells to lesions. We isolated adipose-derived mesenchymal stem cells (AD-MSC) and bone marrow-derived mesenchymal stem cells (BM-MSC) from EGFP-transgenic rats and fabricated the cells in sheet forms using temperature-responsive culture dishes. The MSC sheets were endoscopically transplanted to the inflamed area in electrocoagulation and DNBS colitis model. The effect of the transplantation was verified using endoscopic scoring and histological analysis. In the electrocoagulation model, the AD-MSC group showed significantly decreased ulcer size in the transplanted regions. In the DNBS colitis model, the AD-MSC group showed decreased inflammation and colitis in the transplanted regions. Histologic analysis showed that the MSC sheets had successfully attached to the inflamed mucosa in both the electrocoagulation and DNBS colitis model. Our results show that endoscopic transplantation of MSC sheets could be a new effective mode of stem cell therapy for IBD treatment.

Topics: Animals; Colitis; Dinitrofluorobenzene; Disease Models, Animal; Endoscopes; Green Fluorescent Proteins; Humans; Inflammation; Mesenchymal Stem Cell Transplantation; Mesenchymal Stem Cells; Mice; Rats; Rats, Transgenic

Inflammation of the colon in patients with ulcerative colitis (UC) causes pain and altered motility, at least in part through the damage of the myenteric neurons (MNs). Thus, it is important to evaluate new drugs for UC treatment that could also protect myenteric neurons efficiently. As a well-known neural protective and anti-inflammatory agent, melatonin could protect neurons from damage through the activation of the nuclear factor erythroid 2-related factor 2 and antioxidant responsive element (Nrf2-ARE) signaling pathway. Therefore, we investigated the potential protective effect of melatonin against MN damage during colitis induced by 2,4-dinitrobenzene sulfonic acid (DNBS) in rats. Colitis was induced by intracolonic (i.c.) instillation of DNBS and treated with melatonin at a dose of 2.5 mg/kg for 4 days. The damage of MN in the left colon was immunohistochemically evaluated in different groups. Ulcerations and inflammation in the colon were semiquantitatively observed. Myeloperoxidase (MPO), superoxide dismutase (SOD), and malondialdehyde (MDA) levels were detected to evaluate the inflammatory and oxidative stress status. The protein and mRNA expressions of Nrf2 and heme oxygenase-1 (HO-1) in the colon were detected by Western blot and quantitative polymerase chain reaction (qPCR), respectively. Melatonin partially prevented the loss of MN and alleviated the inflammation and oxidative stress induced by DNBS. In addition, melatonin markedly increased the Nrf2 and HO-1 level in the colitis. These results indicate that melatonin protects MN from damage by reducing inflammation and oxidative stress, effects that are partly mediated by the Nrf2-ARE pathway.

Topics: Animals; Colitis; Colon; Dinitrofluorobenzene; Disease Models, Animal; Heme Oxygenase-1; Inflammation; Malondialdehyde; Melatonin; Neurons; Oxidative Stress; Peroxidase; Protective Agents; Rats; Superoxide Dismutase

Adipose tissue secretes various proteins referred to as adipokines, being involved in inflammation. It was recognized that mesenteric adipose tissue (MAT) is altered by inflammation, and pathologies such as inflammatory bowel disease (IBD). The aim of this study was to investigate the alterations of the mesenteric adipose tissue in two experimental colitis models in mice adapted to obtain moderate colonic inflammation.. Colonic inflammation was obtained using two models, either DSS dissolved in drinking water or intra-colonic instillation of DNBS. The expression of adipokines (leptin and adiponectin) and inflammatory markers (IL-6, MCP-1, F4/80) was studied by qRT-PCR in the MAT of treated and control mice.. Observations of the colon and IL-6 plasma level determination demonstrated that DNBS treatment led to stronger inflammation. Colitis induced a decrease of mRNA encoding to leptin and adiponectin in MAT. In contrast, colonic inflammation led to an increase of mRNA encoding to IL-6, MCP-1 and F4/80, a specific marker of macrophages.. The mesenteric adipose tissue, in two models of moderate colitis, shows a loss of adipose profile and a strong increase of inflammatory pattern, close to the observations made in MAT of IBD patients. These data suggest that these pro-inflammatory modifications of MAT have to be taken into account in the pathophysiology of IBD.

Topics: Adiponectin; Adipose Tissue; Animals; Colitis; Dextran Sulfate; Dinitrofluorobenzene; Disease Models, Animal; Inflammation; Inflammation Mediators; Inflammatory Bowel Diseases; Leptin; Male; Mice; Mice, Inbred BALB C; Proteasome Endopeptidase Complex; Reverse Transcriptase Polymerase Chain Reaction; RNA, Messenger

Sickness behaviors, such as fatigue, mood alterations, and cognitive dysfunction, which result from changes in central neurotransmission, are prevalent in systemic inflammatory diseases and greatly impact patient quality of life. Although, microglia (resident cerebral immune cells) and cytokines (e.g., TNFα) are associated with changes in central neurotransmission, the link between peripheral organ inflammation, circulating cytokine signaling, and microglial activation remains poorly understood. Here we demonstrate, using cerebral intravital microscopy, that in response to liver inflammation, there is increased monocyte specific rolling and adhesion along cerebral endothelial cells (CECs). Peripheral TNFα-TNFR1 signaling and the adhesion molecule P-selectin are central mediators of these monocyte-CEC adhesive interactions which were found to be closely associated with microglial activation, decreased central neural excitability and sickness behavior development. Similar monocyte-CEC adhesive interactions were also observed in another mouse model of peripheral organ inflammation (i.e., 2,4-dinitrobenzene sulfonic acid-induced colitis). Our observations provide a clear link between peripheral organ inflammation and cerebral changes that impact behavior, which can potentially allow for novel therapeutic interventions in patients with systemic inflammatory diseases.

Topics: Alanine Transaminase; Animals; Cell Adhesion; Cerebral Cortex; Cholestasis; Colitis; Cytokines; Dinitrofluorobenzene; Disease Models, Animal; Endothelial Cells; Female; Hippocampus; Illness Behavior; Inflammation; Male; Mice; Mice, Inbred C57BL; Mice, Transgenic; Monocytes; Muramidase; P-Selectin; Pentylenetetrazole

The K(Ca) 3.1 channel is a potential target for therapy of immune disease. We identified a compound from a new chemical class of K(Ca) 3.1 inhibitors and assessed in vitro and in vivo inhibition of immune responses.. We characterized the benzothiazinone NS6180 (4-[[3-(trifluoromethyl)phenyl]methyl]-2H-1,4-benzothiazin-3(4H)-one) with respect to potency and molecular site of action on K(Ca) 3.1 channels, selectivity towards other targets, effects on T-cell activation as well as pharmacokinetics and inflammation control in colitis induced by 2,4-dinitrobenzene sulfonic acid, a rat model of inflammatory bowel disease (IBD).. NS6180 inhibited cloned human K(Ca) 3.1 channels (IC(50) = 9 nM) via T250 and V275, the same amino acid residues conferring sensitivity to triarylmethanes such as like TRAM-34. NS6180 inhibited endogenously expressed K(Ca) 3.1 channels in human, mouse and rat erythrocytes, with similar potencies (15-20 nM). NS6180 suppressed rat and mouse splenocyte proliferation at submicrolar concentrations and potently inhibited IL-2 and IFN-γ production, while exerting smaller effects on IL-4 and TNF-α and no effect on IL-17 production. Antibody staining showed K(Ca) 3.1 channels in healthy colon and strong up-regulation in association with infiltrating immune cells after induction of colitis. Despite poor plasma exposure, NS6180 (3 and 10 mg·kg(-1) b.i.d.) dampened colon inflammation and improved body weight gain as effectively as the standard IBD drug sulfasalazine (300 mg·kg(-1) q.d.).. NS6180 represents a novel class of K(Ca) 3.1 channel inhibitors which inhibited experimental colitis, suggesting K(Ca) 3.1 channels as targets for pharmacological control of intestinal inflammation.

Topics: Animals; Dinitrofluorobenzene; Disease Models, Animal; Erythrocytes; Humans; Inflammation; Inflammatory Bowel Diseases; Intermediate-Conductance Calcium-Activated Potassium Channels; Lymphocyte Activation; Male; Mice; Mice, Knockout; Potassium Channel Blockers; Rats; Rats, Wistar; T-Lymphocytes; Thiazines

Inflammation is known to be associated with changes in tachykinin expression both in human and animal models: substance P and NK(1) receptor expression are increased in patients with inflammatory bowel disease, and similar changes are reported in experimental models of inflammation. We investigated the effect of the tachykinin NK(1) receptor antagonist SR140333 (10 mg/kg orally) on 2,4-dinitrobenzene sulfonic acid (DNBS)-induced colitis in rats. Colonic damage was assessed by means of macroscopic and microscopic scores, myeloperoxidase activity (MPO) and TNF-alpha tissue levels on day 6 after induction of colitis. An enzyme immunoassay technique was used to measure colonic substance P levels. DNBS administration impaired body weight gain and markedly increased all inflammatory parameters as well as colonic tissue levels of substance P. Treatment with SR140333 significantly counteracted the impairment in body weight gain, decreased macroscopic and histological scores and reduced colonic myeloperoxidase activity and TNF-alpha tissue levels. Colonic tissue levels of substance P were also reduced by SR140333, although this effect did not reach statistical significance. In conclusion, treatment with SR140333 protects from DNBS-induced colitis in rats. These results suggest a role for NK(1) receptors and substance P in the development of intestinal inflammation and indicate tachykinin receptors as a potential pharmacological target in the treatment of inflammatory bowel disease.

Topics: Animals; Colitis; Dinitrofluorobenzene; Humans; Inflammation; Intestinal Mucosa; Intestines; Male; Piperidines; Quinuclidines; Rats; Rats, Sprague-Dawley; Receptors, Tachykinin; Substance P; Substrate Specificity; Tumor Necrosis Factor-alpha

Although macrophages are considered a critical factor in determining the severity of acute inflammatory responses in the gut, recent evidence has indicated that macrophages may also play a counterinflammatory role. In this study, we examined the role of a macrophage subset in two models of colitis. Macrophage colony-stimulating factor (M-CSF)-deficient osteopetrotic mice (op/op) and M-CSF-expressing heterozygote (+/?) mice were studied following the induction of colitis by either dinitrobenzene sulfonic acid (DNBS) or dextran sulfate sodium (DSS). DNBS induced a severe colitis in M-CSF-deficient op/op mice compared with +/? mice. This was associated with increased mortality and more severe macroscopic and microscopic injury. Colonic tissue myeloperoxidase (MPO) activity as well as concentrations of TNF-alpha, IL-1beta, and IL-6 were higher and IL-10 lower in op/op mice with DNBS colitis. The severity of inflammation and mortality was attenuated in op/op mice that had received human recombinant M-CSF prior to the induction of colitis. In contrast, op/op mice appeared less vulnerable to colitis induced by DSS. Macroscopic damage, microscopic injury, MPO activity, and tissue concentrations of TNF-alpha, IL-1beta, and IL-6 were all lower in op/op mice compared with +/? mice with DSS colitis, and no changes were seen in IL-10. Macrophage inflammatory protein-1alpha concentrations were increased in op/op but not +/? mice following colitis induced by DNBS but not DSS. These results indicate that M-CSF-dependent macrophages may play either a pro- or counterinflammatory role in acute experimental colitis, depending on the stimulus used to induce colitis.

Topics: Animals; Benzenesulfonates; Colitis; Cytokines; Data Interpretation, Statistical; Dextran Sulfate; Dinitrofluorobenzene; Immunohistochemistry; Inflammation; Macrophage Colony-Stimulating Factor; Macrophages; Mice; Mice, Knockout; Peroxidase; Receptors, CCR1

Beta(3)-adrenoceptor agonists protect against experimental gastric ulcers. We investigated the effects of the beta(3)-adrenoceptor agonist SR58611A on 2,4-dinitrobenzene sulphonic acid-induced colitis in rats and analysed the expression of beta(3)-adrenoceptors in the colonic wall. SR58611A was administered orally (1-10 mg kg(-1)) for 7 days, starting the day before induction of colitis. Colitis was assessed by macroscopic and histological scores, tissue myeloperoxidase activity, interleukin-1beta (IL-1beta), interleukin-6 (IL-6) and tumour necrosis factor-alpha (TNF-alpha) levels. Reverse transcription-polymerase chain reaction and immunohistochemical analysis were used to examine the expression of beta(3)-adrenoceptors. SR58611A significantly reduced the severity of colitis as well as the tissue levels of TNF-alpha, IL-1beta and IL-6. Colitis was associated with a decreased expression of beta(3)-adrenoceptor mRNA in the mucosal/submucosal layer of distal colon and this reduction was not affected by SR58611A. Immunohistochemical analysis revealed beta(3)-adrenoceptors within the muscularis externa, in myenteric neurons and nerve fibres and in the submucosa. beta(3)-Adrenoceptor immunoreactivity was decreased in inflamed tissues compared to controls, particularly in the myenteric plexus; this reduction was counteracted by SR58611A. Amelioration of experimental colitis by the selective beta(3)-adrenoceptor agonist SR58611A suggests that beta(3)-adrenoceptors may represent a therapeutic target in gut inflammation.

Topics: Adrenergic beta-3 Receptor Agonists; Adrenergic beta-Agonists; Animals; Body Weight; Colitis; Colon; Cytokines; Dinitrofluorobenzene; Dose-Response Relationship, Drug; Humans; Inflammation; Male; Proto-Oncogene Proteins c-kit; Rats; Rats, Sprague-Dawley; Receptors, Adrenergic, beta-3; Tetrahydronaphthalenes

High-density lipoproteins (HDLs) have been shown to reduce the organ injury and mortality in animal models of shock by reducing the expression of adhesion molecules and proinflammatory enzymes. However, there is limited evidence that HDL treatment reduces inflammation. As inflammation plays an important role in the development of colitis as well as ischemia/reperfusion (I/R) injury of the intestine, we have investigated the effects of HDL in animal models of associated with gut injury and inflammation (splanchnic artery occlusion [SAO] shock and dinitrobenzene sulfonic acid [DNBS]-induced colitis). We report here for the first time that the administration of reconstituted HDLs (recHDLs; 80 mg/kg i.v. bolus 30 min prior to ischemia in the SAO-shock model or 40 mg/kg i.v. every 24 h in the colitis model) exerts potent anti-inflammatory effects (e.g., reduced inflammatory cell infiltration and histological injury, and delayed the development of the clinical signs) in vivo. Furthermore, recHDL reduced the staining for nitrotyrosine and poly(ADP-ribose) (immunohistochemistry) and the expression of intercellular adhesion molecule-1 in the ileum of SAO-shocked rats and in the colon from DNBS-treated rats. Thus, recHDL reduces the inflammation caused by intestinal I/R and colitis. HDLs may represent a novel therapeutic approach for the therapy of inflammation of the gut.

Topics: Animals; Colitis; Dinitrofluorobenzene; Immunohistochemistry; Inflammation; Intercellular Adhesion Molecule-1; Intestines; Lipoproteins, HDL; Male; Rats; Rats, Sprague-Dawley; Reperfusion Injury; Tyrosine

L-selectin, an adhesion molecule constitutively expressed on leukocytes, is important for primary adhesion and extravasation of lymphocytes at specialized high endothelial venules within lymph nodes and other leukocytes at sites of inflammation. We have generated L-selectin-deficient mice by targeted disruption, and have confirmed a previously reported phenotype which includes strikingly impaired contact hypersensitivity (CHS) responses to reactive haptens (Tedder, T.F., D.A. Steeber, and P. Pizcueta. 1995. J. Exp. Med. 181:2259-2264; Xu, J.C., I.S. Grewal, G.P. Geba, and R.A. Flavell. 1996. 183:589-598.). Since the mechanism of this impairment has not been clarified, we sought to define the stage(s) at which the CHS response is affected in L-selectin-deficient mice. We show that epidermal Langerhans cells in L-selectin-deficient mice are normal in number, migrate to peripheral lymph nodes appropriately, and are functional in presenting allogeneic and haptenic antigens. Moreover, T cells, as well as neutrophil and monocyte effector populations, are fully capable of entry into the inflamed skin sites in the absence of L-selectin. Thus, antigen presentation and effector mechanisms are intact in L-selectin deficient mice. In contrast, virtually no antigen-specific T cells can be found within draining peripheral nodes after a contact challenge, suggesting that the defect resides primarily in the inability of antigen-specific T cells to home to and be activated in these nodes. Indeed, L-selectin-deficient mice mount completely normal CHS responses when alternate routes of immunization are used. These studies pinpoint the lesion in CHS to a discrete stage of the afferent limb of the response, clarify the role of L-selectin on effector populations, and illustrate the critical importance of the route of antigen entry to the successful execution of an immune response.

Topics: Adoptive Transfer; Animals; Antigens; Dermatitis, Contact; Dinitrofluorobenzene; Hypersensitivity, Delayed; Inflammation; L-Selectin; Langerhans Cells; Lymphocyte Activation; Mice; Mice, Inbred C57BL; Mice, Mutant Strains; Monocytes; Neutrophils; Skin; Spleen; T-Lymphocytes