Effects of aryl hydrocarbon receptor on Th17 cells activation in a murine model of irritable bowel syndrome / 中华微生物学和免疫学杂志

ABSTRACT

Objective To detect the dynamic Th17 cells in a murine model of irritable bowel syn-drome ( IBS) and to study the effect of aryl hydrocarbon receptor ( Ahr) on Th17 cells activation .Methods Thirty BALB/c male mice were randomly divided into three groups including experiment group ,control group and Ahr antagonist group .A murine model of IBS was established by perfusing three nitrobenzene sulfonic acid (TNBS) into the colon of mice.Equal volume of saline was used to set up the control .The mice in Ahr antagonist group were intraperitoneally injected with 10 μg Ahr antagonist for four consecutive days .All mice were evaluated for visceral hypersensitivity and colonic mucosal inflammation .Mesenteric lymph nodes (MLNs) and peripheral blood mononuclear cells (PBMCs) were detected by flow cytometry through staining Th17 cells.The distribution of Ahr and IL-17A in colon and the number of Th17 cells activated by Ahr (Ahr and IL-17A double positive ) were detected by double immunofluorescence staining .Results ( 1 ) The percentage of Th17 cells in MLNs was significantly increased in experiment group followed by those in Ahr antagonist group and control group (P<0.05).(2)Compared with control group,the number of Th17 cells in peripheral blood samples was significantly increased in experiment group and Ahr antagonist group ( both P<0.05 ) ,but there was no difference between Ahr antagonist group and experiment group ( P=0.642 ) .( 3 ) The number of Ahr-activated Th17 cells ( Ahr+IL-17A+) was significantly increased in experiment group (10.00±1.58) as in comparison with that in control group (3.80±0.83,P<0.05),but the number was de-creased with Ahr antagonist intervention ( 5.80 ±0.83 , P<0.05 ) .Conclusion The number of activated Th17 cells was increased in MLNs and peripheral blood samples from mice with IBS .Ahr played an important role in the activation of Th17 cells in intestines.However,the number of Ahr-activated Th17 cells in intestinal mucosa and the proportion of Th 17 cells in MLNs could be down-regulated through blocking Ahr .