ABSTRACT
OBJECTIVE: To explore the probable role of Th1 and Th17 cells in the pathogenesis of inflammatory bowel disease (IBD). METHODS: The peripheral blood mononuclear cells (PBMCs) from peripheral blood specimens were collected in the study, including 40 healthy controls, 42 ulcerative colitis (UC) and 39 Crohn's disease (CD). The proportion of Th1 and Th17 cells in the PBMCs was detected with flow cytometry after stimulated by PMA and ionomycin. The result and the clinical data were analyzed. RESULT: The Th1 cell expression was increased in CD (38.32 ± 16.18)% and UC group (34.23 ± 11.60)%, compared with the controls (24.58 ± 10.02)% (P < 0.01). During the convalescence, the Th1 expression in the CD and UC groups in vivo was significantly reduced without difference between the two groups (P > 0.05) . In the IBD group , significant difference in the frequency of Th17 cells could be found between the CD group (2.51 ± 1.59)% and the UC group (4.15 ± 2.75)%, while the Th17 cells were increased in both groups, compared with the controls (1.44 ± 0.73)% (P < 0.05) . Obvious difference in the frequency of Th17 cells could be found between patients at different activity stages and remission stages. The proportion of Th17 cells were higher in the UC patients than that in the CD patients (P < 0.01) . The Th17/Th1 ratio of CD patients, UC patients were 0.08 ± 0.06, 0.14 ± 0.11, which were both higher that in the controls (0.07 ± 0.06). Significant difference could be found between the UC group and the CD group (P < 0.01). CONCLUSIONS: The higher proportion of Th1 and Th17 cells are detected in the peripheral blood of IBD patients, which is correlated closely to the activity of the disease. Th1 and Th17 cells may play an important role in the pathogenesis of IBD.