RESUMO
Objects To explore the association of ulcerative colitis (UC) with the imbalance between Th1,Th 2 and Th17 cells in the colonic tissues.Methods A total of 41 UC patients and 52 controls was recruited in the present study.The real-time fluorescent quantitative PCR was applied for detecting the mRNA levels of Thl,Th2 and Th 17 cells-associated transcription factors T-bet,GATA-3 and RORγt and cytokines IFN-γ,IL-4 and IL-17A in the colonic tissues.Simultaneously,the expressions of IFN-γ,IL-4 and IL-17A in the colonic tissues were also examined by an immunohistochemical staining method.Results Compared with the controls,the mRNA expressions of GATA-3,RORγt and IL-17A were more significantly enhanced in UC patients (0.84 ± 0.24 vs.0.69 ± 0.22,P=0.002;0.99 ± 0.29 vs.0.83 ± 0.23,P=0.004;1.59 ± 0.65 vs.1.35 ± 0.43,P=0.035).According to the "Truelove and Witts Severity Index",those patients were divided into different subgroups.The mRNA expressions of GATA-3,RORγt,and IL-17A were shown to be higher in patients with moderate and severe UC than in those with mild UC (0.90 ± 0.18 vs.0.78 ± 0.16,P=0.030;1.11 ± 0.31 vs.0.87 ± 0.26,P=0.011;1.83 ± 0.64 vs.1.34 ± 0.66,P=0.020).Moreover,the immunohistochemistry results demonstrated that the IL-17A positive cells were positioned mainly in the intestinal epithelial layer and lamina propria.Compared to the controls,the mean integral optic density of IL-17A was significantly increased in the colonic tissues of UC patients (0.25 ± 0.07 vs.0.13 ± 0.03,P<0.001).The similar results were obtained for IL-17A in patients with moderate and severe UC when compared to those with mild UC (0.31 ± 0.07 vs.0.19 ± 0.06,P<0.001).In contrast to the controls,the mRNA ratios ofGATA-3/T-bet,RORγt/ T-bet and RORγt/GATA-3 were significantly higher in the tissues of colonic UC patients (1.12 ± 0.30 vs.0.96 ± 0.31,P=0.014;1.33 ± 0.37 vs.1.15 ± 0.33,P=0.015;1.44 ± 0.45 vs.1.20 ± 0.42,P=0.009),and in the patients,the mRNA ratios for GATA-3/T-bet,RORγt/T-bet and RORγt/GATA-3 were significantly higher in the patients with moderate and severe UC than in those with mild UC (1.27 ± 0.35 vs.1.00 ± 0.32,P<0.001;1.45 ± 0.37 vs.1.19 ± 0.36,P=0.028;1.59 ± 0.43 vs.1.28 ± 0.46,P=0.031).Conclusions These findings suggest that the imbalance between Thl,Th2 and Th17 cells in the colonic tissues may be implicated in UC.