Phenotypic Analysis Of Th Cells In IBS And IBD

PartⅠPhenotypic analysis of Th cells in the colon and peripheralblood in patients with ulcerative colitisObjective To analyse the proportion of Th1/Th2/Th17 in colonic mucosa and peripheralblood in ulcerative colitis in relation to healthy controls.Methods Colonic biopsy specimens and peripheral blood were obtained from controls(n=16) and patients with UC (n=20) .We used flow cytometric detection of intracellularIFN-γ/IL-4/ IL-17 cytokine production to investigate Th1,Th2 and Th17 cells in thecolonic lamina propria and peripheral blood.The levels of IL-12,IL-4 and IL-17 inintestinal mucosa and peripheral blood were explored by Western blot and ELISA,respectively.Results In colonic mucosa,the proportion of Th17 and the expression of IL-17increased in UC compared with controls (P＜0.05).The expression of IL-17 in the colonwas correlated with the disease related clinical parameters in UC patients (r=0.503,P=0.024).The frequency of Th17 in severely active UC was higher than in slightly activeUC in colonic mucosa (P＜0.05).In peripheral blood,the proportion of Th17 and the expression of IL-17 was upregulated in moderately and severely active UC (P＜0.05) Nodifferences were found in the proportions of Th1 or Th2 in colonic mucosa or peripheralblood between UC and controls.The contents of IL-4 and IL-12 in colonic mucosa orperipheral blood showed no differences between UC and controls.Conclusions In UC patients,Th17 is predominant of three Helper T-Cells both in colonicmucosa and peripheral blood.Th17 would be an effective target for treatment.PartⅡPhenotypic analysis of Th cells in the colon and peripheralblood in patients with diarrhea-predominant IBSObjective We analyse the change of Th1/Th2/Th17 in colonic mucosa and peripheralblood in diarrhea-predominant IBS (D-IBS) to uncover the mechanism underlying theactivation of mucosal immune system.Methods Colonic biopsy specimens and peripheral blood were obtained from controls(n=16) and patients with D-IBS (n = 27) .We used flow cytometric detection of intracellularIFN-γ/IL-4/ IL-17 cytokine production to investigate Th1,Th2 and Th17 cells in thecolonic lamina propria and peripheral blood.Western blot was used to determine theexpression of IL-12,IL-4 and IL-17 in colonic mucosa.The level of IL-12,IL-4 and IL-17in peripheral blood was detected by ELISA.Results Histological assessment of biopsy specimens from D-IBS patients indicated 2 different groups.One group (14 of 27) had normal conventional histology (IBS).Anothergroup (13 of 27) had nonspecific microscopic inflammation (IBS-A).In colonic mucosa,the proportion of Th17 increased in IBS-A compared with controls (P＜0.05),but not in IBS.In peripheral blood,a similar tendency was found although differences were not significant.No differences could be observed in the frequencies of Th1 and Th2 in colon mucosa andperipheral blood.The level of IL-12,IL-4 and IL-17 in IBS and IBS-A showed nodifferences both in colonic mucosa and in peripheral blood.Conclusions Subgroup of D-IBS showed abnormal conventional histology,implicating theactivation of mucosal immune system in pathogenesis.The shift of Th1/ Th2 / Th17balance in colon mucosa showed enhanced Th17 activity.PartⅢThe role of Th17 in visceral hypersensitivity in mice infectedwith Trichinella spiralisObjective Trichinella spiralis infection in rodents is a well-known model of intestinalinflammation associated with hypermotility.Our aim was to use this experimental model toelucidate if Th17 cells were involved in the development of gastrointestinal hypermotility.Methods Mice were divided into four groups;control,2 weeks post infection,8 weekspost infection and 12 weeks post infection.Inflammation in jejunum and colon was judgedby hematoxylin-eosin (H&E) staining.Visceral hypersensitivity was measured byabdominal withdraw reflex (AWR).The levels of IL- 17,IL-23 and TGF-β1 in jejunum and colon were detected by Western blot.Flow cytometric detection of intracellular IL-17cytokine production was used to analysis the proportions of Th17 cells subset in jejunumand colon.Results Our results showed that visceral hypersensitivity was increased at 2 weeks postinfection (PI) and kept higher at 8 and 12 weeks PI when no discernible inflammationpresented in the gut.The proportion of Th17 cells and the expression of IL-17 wereupregulated in jejunum and colon at 2 weeks PI and normalized at 8 weeks PI.The contentof IL-17 in jejunum and colon was correlated with the AWR at 2 weeks PI.Meanwhile,injejunum and colon TGF-β1 was increased at 2 weeks PI in jejunum and colon,while IL-23was in the normal condition.Conclusions Our data suggest that Th17 cells affected the visceral hypersensitivity inmice infected with Trichinella spiralis at intestine stage in support of TGF-β1,but not atmuscle stage when other cytokines might involved in the visceral hypersensitivity.