Wednesday, July 15, 2015
Grand Hall and Gallery, Ground Floor & 1st Floor (Maritim Hotel)
Introduction: Double Positive (DP, CD3+CD4+CD8+) and Double Negative (DN, CD3+CD4-CD8-) T cells are two rare T cell subsets with a poorly understood role in intestinal and systemic immunity. Aim: To evaluate DP and DN T cells presence in different bowel locations and in inflammatory bowel disorders.
Methods: 20 Crohn's Disease (CD), 7 ulcerative colitis (UC), 5 infectious colitis (IC) and 14 collagenous colitis (CC) patients were included in the study, all of them with active disease and without treatment. Ileum, right and left colon samples from 16 healthy controls (HC) were compared in a paired manner. DP and DN T cells were analyzed by flow cytometry in biopsy specimens and in peripheral blood. Results: A reduction of peripheral DN T cells was found in CD patients compared to HC (p=0.036). DN T cells were reduced in colonic CD (p=0.005) but not in ileal CD compared to HC (p=0.452). In contrast, DN T cells were increased in CC compared to HC (p=0.038), whereas no differences were found in IC or UC. No differences in DP T cell peripheral or mucosal lymphocytes were found between healthy and patients with inflammatory bowel disorders. However, a significant increase of DP T cells was observed in ileal samples compared to colonic samples, both in HC (0.028) and CD (0.016) groups. Conclusions: DN T cells are reduced in colonic CD and increased in colonic CC, suggesting that this subset could have a role in those intestinal disorders. The ileal increase in healthy and inflammed mucosa suggests that DP T cells could have a role in intestinal homeostasis regulation.
Methods: 20 Crohn's Disease (CD), 7 ulcerative colitis (UC), 5 infectious colitis (IC) and 14 collagenous colitis (CC) patients were included in the study, all of them with active disease and without treatment. Ileum, right and left colon samples from 16 healthy controls (HC) were compared in a paired manner. DP and DN T cells were analyzed by flow cytometry in biopsy specimens and in peripheral blood. Results: A reduction of peripheral DN T cells was found in CD patients compared to HC (p=0.036). DN T cells were reduced in colonic CD (p=0.005) but not in ileal CD compared to HC (p=0.452). In contrast, DN T cells were increased in CC compared to HC (p=0.038), whereas no differences were found in IC or UC. No differences in DP T cell peripheral or mucosal lymphocytes were found between healthy and patients with inflammatory bowel disorders. However, a significant increase of DP T cells was observed in ileal samples compared to colonic samples, both in HC (0.028) and CD (0.016) groups. Conclusions: DN T cells are reduced in colonic CD and increased in colonic CC, suggesting that this subset could have a role in those intestinal disorders. The ileal increase in healthy and inflammed mucosa suggests that DP T cells could have a role in intestinal homeostasis regulation.