tretinoin and Crohn-Disease

Crohn's disease (CD) is characterized by an imbalance of effector and regulatory T cells in the intestinal mucosa. The efficacy of anti-adhesion therapies led us to investigate whether impaired trafficking of T-regulatory (Treg) cells contributes to the pathogenesis of CD. We also investigated whether proper function could be restored to Treg cells by ex vivo expansion in the presence of factors that activate their regulatory activities.. We measured levels of the integrin α4β7 on Treg cells isolated from peripheral blood or lamina propria of patients with CD and healthy individuals (controls). Treg cells were expanded ex vivo and incubated with rapamycin with or without agonists of the retinoic acid receptor-α (RARA), and their gene expression profiles were analyzed. We also studied the cells in cytokine challenge, suppression, and flow chamber assays and in SCID mice with human intestinal xenografts.. We found that Treg cells from patients with CD express lower levels of the integrin α4β7 than Treg cells from control patients. The pathway that regulates the expression of integrin subunit α is induced by retinoic acid (RA). Treg cells from patients with CD incubated with rapamycin and an agonist of RARA (RAR568) expressed high levels of integrin α4β7, as well as CD62L and FOXP3, compared with cells incubated with rapamycin or rapamycin and all-trans retinoic acid. These Treg cells had increased suppressive activities in assays and migrated under conditions of shear flow; they did not produce inflammatory cytokines, and RAR568 had no effect on cell stability or lineage commitment. Fluorescently labeled Treg cells incubated with RAR568 were significantly more likely to traffic to intestinal xenografts than Treg cells expanded in control medium.. Treg cells from patients with CD express lower levels of the integrin α4β7 than Treg cells from control patients. Incubation of patients' ex vivo expanded Treg cells with rapamycin and an RARA agonist induced expression of α4β7 and had suppressive and migratory activities in culture and in intestinal xenografts in mice. These cells might be developed for treatment of CD. ClinicalTrials.gov, Number: NCT03185000.

Topics: Adult; Animals; Antineoplastic Agents; Case-Control Studies; Cell Culture Techniques; Cell Movement; Cells, Cultured; Crohn Disease; Female; Forkhead Transcription Factors; Gene Expression; Heterografts; Humans; Immunosuppressive Agents; Integrins; Intestinal Mucosa; L-Selectin; Lymphocyte Activation; Male; Mice; Mice, SCID; Middle Aged; Organic Chemicals; Retinoic Acid Receptor alpha; Sirolimus; T-Lymphocytes, Regulatory; Transcriptome; Tretinoin

Repair of tissue damaged during inflammatory processes is key to the return of local homeostasis and restoration of epithelial integrity. Here we describe CD161

Topics: Crohn Disease; Humans; Intestinal Mucosa; NK Cell Lectin-Like Receptor Subfamily B; T-Lymphocyte Subsets; T-Lymphocytes, Regulatory; Tretinoin; Wound Healing

Human group 1 ILCs consist of at least three phenotypically distinct subsets, including NK cells, CD127(+) ILC1, and intraepithelial CD103(+) ILC1. In inflamed intestinal tissues from Crohn's disease patients, numbers of CD127(+) ILC1 increased at the cost of ILC3. Here we found that differentiation of ILC3 to CD127(+) ILC1 is reversible in vitro and in vivo. CD127(+) ILC1 differentiated to ILC3 in the presence of interleukin-2 (IL-2), IL-23, and IL-1β dependent on the transcription factor RORγt, and this process was enhanced in the presence of retinoic acid. Furthermore, we observed in resection specimen from Crohn's disease patients a higher proportion of CD14(+) dendritic cells (DC), which in vitro promoted polarization from ILC3 to CD127(+) ILC1. In contrast, CD14(-) DCs promoted differentiation from CD127(+) ILC1 toward ILC3. These observations suggest that environmental cues determine the composition, function, and phenotype of CD127(+) ILC1 and ILC3 in the gut.

Topics: Animals; Cell Differentiation; Cells, Cultured; Crohn Disease; Dendritic Cells; Humans; Interleukin-12 Subunit p35; Interleukin-1beta; Interleukin-2; Interleukin-23 Subunit p19; Interleukin-7 Receptor alpha Subunit; Intestinal Mucosa; Killer Cells, Natural; Lipopolysaccharide Receptors; Lymphocyte Transfusion; Lymphocytes; Mice; Mice, Inbred C57BL; Mice, Inbred NOD; Mice, Knockout; Mice, SCID; Nuclear Receptor Subfamily 1, Group F, Member 3; Receptors, Retinoic Acid; Retinoic Acid Receptor alpha; Retinoic Acid Receptor gamma; Retinoid X Receptor gamma; Tretinoin

Reduced generation of all-trans retinoic acid (RA) by CD103(+) intestinal dendritic cells (DCs) is linked to intestinal inflammation in mice. However, the role of RA in intestinal inflammation in humans is unclear. We investigated which antigen-presenting cells (APCs) produce RA in the human intestine and whether generation of RA is reduced in patients with Crohn's disease (CD).. Ileal and colonic tissues were collected from patients with CD during endoscopy or surgery, and healthy tissues were collected from subjects who were undergoing follow-up because of rectal bleeding, altered bowel habits, or cancer (controls). Cells were isolated from the tissue samples, and APCs were isolated by flow cytometry. Retinaldehyde dehydrogenase (RALDH) activity was assessed by Aldefluor assay, and ALDH1A expression was measured by quantitative real-time polymerase chain reaction. Macrophages were derived by incubation of human blood monocytes with granulocyte-macrophage colony-stimulating factor (GM-CSF).. CD103(+) and CD103(-) DCs and CD14(+) macrophages from healthy human intestine had RALDH activity. Although ALDH1A1 was not expressed by DCs, it was the predominant RALDH enzyme isoform expressed by intestinal CD14(+) macrophages and their putative precursors, CD14(+) monocytes. RALDH activity was up-regulated in all 3 populations of APCs from patients with CD; in CD14(+) macrophages, it was associated with local induction of ALDH1A1 expression. Blocking of RA receptor signaling during GM-CSF-mediated differentiation of monocytes into macrophages down-regulated CD14 and HLA-DR expression and reduced the development of tumor necrosis factor α-producing inflammatory macrophages.. RA receptor signaling promotes differentiation of human tumor necrosis factor α-producing inflammatory macrophages in vitro. In vivo, more CD14(+) macrophages from the intestinal mucosa of patients with CD than from controls are capable of generating RA, which might increase the inflammatory phenotype of these cells. Strategies to reduce the generation of RA by CD14(+) macrophages could provide new therapeutic options for patients with CD.

Topics: Aldehyde Dehydrogenase; Aldehyde Dehydrogenase 1 Family; Antigens, CD; Case-Control Studies; Cells, Cultured; Colon; Crohn Disease; Dendritic Cells; Gene Expression Regulation, Enzymologic; Humans; Ileum; Integrin alpha Chains; Intestinal Mucosa; Lipopolysaccharide Receptors; Macrophages; Phenotype; Receptors, Retinoic Acid; Retinal Dehydrogenase; Retinoic Acid Receptor alpha; Signal Transduction; Tretinoin; Up-Regulation

Several studies suggest that Vitamin A may be involved in the pathogenesis of inflammatory bowel disease (IBD), but the mechanism is still unknown. Cytochrome P450 26 B1 (CYP26B1) is involved in the degradation of retinoic acid and the polymorphism rs2241057 has an elevated catabolic function of retinoic acid, why we hypothesized that the rs2241057 polymorphism may affect the risk of Crohn's disease (CD) and Ulcerative Colitis (UC). DNA from 1378 IBD patients, divided into 871 patients with CD and 507 with UC, and 1205 healthy controls collected at Örebro University Hospital and Karolinska University Hospital were analyzed for the CYP26B1 rs2241057 polymorphism with TaqMan® SNP Genotyping Assay followed by allelic discrimination analysis. A higher frequency of patients homozygous for the major (T) allele was associated with CD but not UC compared to the frequency found in healthy controls. A significant association between the major allele and non-stricturing, non-penetrating phenotype was evident for CD. However, the observed associations reached borderline significance only, after correcting for multiple testing. We suggest that homozygous carriers of the major (T) allele, relative to homozygous carriers of the minor (C) allele, of the CYP26B1 polymorphism rs2241057 may have an increased risk for the development of CD, which possibly may be due to elevated levels of retinoic acid. Our data may support the role of Vitamin A in the pathophysiology of CD, but the exact mechanisms remain to be elucidated.

Topics: Adult; Alleles; Case-Control Studies; Colitis, Ulcerative; Crohn Disease; Cytochrome P-450 Enzyme System; Female; Gene Frequency; Genetic Association Studies; Genetic Predisposition to Disease; Humans; Male; Polymorphism, Single Nucleotide; Retinoic Acid 4-Hydroxylase; Tretinoin

The chemokine system represents a diverse group of G protein-coupled receptors responsible for orchestrating cell recruitment under both homeostatic and inflammatory conditions. Chemokine receptor 9 (CCR9) is a chemokine receptor known to be central for migration of immune cells into the intestine. Its only ligand, CCL25, is expressed at the mucosal surface of the intestine and is known to be elevated in intestinal inflammation. To date, there are no reports of small-molecule antagonists targeting CCR9. We report, for the first time, the discovery of a small molecule, CCX282-B, which is an orally bioavailable, selective, and potent antagonist of human CCR9. CCX282-B inhibited CCR9-mediated Ca(2+) mobilization and chemotaxis on Molt-4 cells with IC(50) values of 5.4 and 3.4 nM, respectively. In the presence of 100% human serum, CCX282-B inhibited CCR9-mediated chemotaxis with an IC(50) of 33 nM, and the addition of α1-acid glycoprotein did not affect its potency. CCX282-B inhibited chemotaxis of primary CCR9-expressing cells to CCL25 with an IC(50) of 6.8 nM. CCX282-B was an equipotent inhibitor of CCL25-directed chemotaxis of both splice forms of CCR9 (CCR9A and CCR9B) with IC(50) values of 2.8 and 2.6 nM, respectively. CCX282-B also inhibited mouse and rat CCR9-mediated chemotaxis. Inhibition of CCR9 with CCX282-B results in normalization of Crohn's disease such as histopathology associated with the TNF(ΔARE) mice. Analysis of the plasma level of drug associated with this improvement provides an understanding of the pharmacokinetic/pharmacodynamic relationship for CCR9 antagonists in the treatment of intestinal inflammation.

Topics: Administration, Oral; Animals; Calcium; Cell Line; Chemotaxis, Leukocyte; Crohn Disease; Gastrointestinal Agents; Humans; Ileitis; Inflammatory Bowel Diseases; Mice; Mice, Inbred C57BL; Radioligand Assay; Rats; Receptors, CCR; Sulfonamides; T-Lymphocytes; Tretinoin; Tumor Necrosis Factor-alpha

Topics: Adolescent; Antineoplastic Agents; Antineoplastic Combined Chemotherapy Protocols; Crohn Disease; Female; Humans; Leukemia, Promyelocytic, Acute; Tretinoin

Retinoic acid plays a positive role in induction of FoxP3(+) regulatory T cells. Because retinoic acid is produced as a metabolite of vitamin A in the intestine and FoxP3(+) T cells regulate intestinal inflammation, we investigated the impact of vitamin A status on the regulatory T cells and inflammation in the intestine.. The SAMP1/YP model is a mouse model of Crohn's disease. We made vitamin A-deficient, vitamin A-excessive, and normal SAMP1/YP mice and assessed the intestinal inflammation. We also investigated the phenotype and function of FoxP3(+) T cells induced in different levels of vitamin A availability in regulation of intestinal inflammation in a T-cell-induced inflammation model in SCID mice.. The limited and excessive vitamin A conditions induced distinct FoxP3(+) T-cell subsets in vivo, and both ameliorated the intestinal inflammation in SAMP1/YP mice. The limited vitamin A condition greatly induced unusual CD103(+)CCR7(+) FoxP3(+) cells, while the high vitamin A condition induced CCR9(+)alpha4beta7(+) FoxP3(+) T cells in the intestine. Both FoxP3(+) T-cell populations, when transferred into mice with ongoing intestinal inflammation, were highly effective in reversing the inflammation. Blockade or lack of occupancy of RARalpha is a mechanism to induce highly suppressive CD103(+)CCR7(+) FoxP3(+) cells in both the thymus and periphery in limited vitamin A availability.. Our results identify novel pathways of inducing highly suppressive FoxP3(+) regulatory T cells that can effectively control intestinal inflammation. The results have significant ramifications in treating inflammatory bowel diseases.

Topics: Adoptive Transfer; Animals; Anti-Inflammatory Agents; Antigens, CD; Cell Movement; Cells, Cultured; Coculture Techniques; Crohn Disease; Disease Models, Animal; Forkhead Transcription Factors; Gastrointestinal Agents; Immunophenotyping; Integrin alpha Chains; Intestines; Mice; Mice, Inbred BALB C; Mice, SCID; Receptors, CCR; Receptors, CCR7; Receptors, Retinoic Acid; Retinoic Acid Receptor alpha; Spleen; T-Lymphocyte Subsets; Th1 Cells; Th2 Cells; Thymus Gland; Tretinoin; Vitamin A; Vitamin A Deficiency

The mouse model of 2,4,6-Trinitrobenzene Sulfonic Acid (TNBS)-induced intestinal fibrosis allows for detailed study of the extracellular matrix changes that complicate Crohn's disease. Indomethacin induces intestinal fibrosis, while retinoic acid (RA) reduces liver fibrosis. Secreted protein acidic and rich in cysteine (SPARC), an extracellular matrix-modifying agent, may potentially link these opposing effects. Our aim was to determine the effects of indomethacin and RA and to evaluate their correlation to SPARC expression in the TNBS mouse model. CD-1 mice were randomised to TNBS enemas weekly for 2 or 8 weeks with or without indomethacin (0.2 mg/kg per day) or RA (100 microg/kg per day). At 2 weeks, indomethacin/TNBS enhanced and RA reduced inflammation, tissue destruction and fibrosis. The expression of SPARC was inversely related to fibrosis, but not to inflammation, in the TNBS-alone groups at 2 weeks; these differences were lost by 8 weeks. The results demonstrate that indomethacin increases TNBS-induced fibrosis in mice, while RA reduces it, and that SPARC may link these opposing effects.

Topics: Animals; Crohn Disease; Disease Models, Animal; Female; Fibrosis; Immunoenzyme Techniques; Indomethacin; Mice; Osteonectin; Random Allocation; Reverse Transcriptase Polymerase Chain Reaction; RNA; Statistics, Nonparametric; Tretinoin; Trinitrobenzenesulfonic Acid

Topics: Antineoplastic Agents; Crohn Disease; Humans; Leukemia, Promyelocytic, Acute; Leukocyte Count; Male; Middle Aged; Tretinoin