Decreased Breg/Th17 Ratio Improved the Prognosis of Patients with Ulcerative Colitis

OBJECTIVE: To investigate the effects of regulatory B (Breg) cells and T helper 17 (Th17) cells on pathogenesis of ulcerative colitis, explore the clinical significance of Breg/Th17 ratio on the prognosis of ulcerative colitis, and provide the theoretical basis for the targeted therapy, diagnosis, and prognosis of the disease. METHODS: Peripheral blood and colonic mucosa were collected from patients with ulcerative colitis. Hematoxylin-eosin staining was used to observe the pathological changes of colonic mucosa. Flow cytometry was utilized to analyze the percentages of Breg cells and Th17 cells. Real-time fluorescent quantitative polymerase chain reaction and immunohistochemistry were applied to determine the expression of Breg cells-related cytokines IL-10 and Th17 cell transcription factor RORγT. Enzyme-linked immunosorbent assay was employed to detect serum IL-10 and IL-17 levels. RESULTS: The colonic mucosa of ulcerative colitis patients presented massive inflammatory cell infiltration and hemorrhagic necrosis. The number of Breg cells and Th17 cells, the gene expressions of IL-10 and RORγT, and serum levels of IL-10 and IL-17 all increased in peripheral blood. Compared with nonremission group, the remission group showed that the percentage of Breg cells reduced, the percentage of Th17 cells increased, and thus the B10/Th17 ratio was significantly decreased in peripheral blood. In addition, serum IL-10 levels diminished, IL-17 levels increased, and thus IL-10/IL-17 ratio was remarkably reduced in remission group. B10/Th17 ratio and IL-10/IL-17 ratio were positively correlated with the severity of disease. CONCLUSIONS: Breg and Th17 cells participate in the occurrence and development of ulcerative colitis. B10/Th17 ratio and IL-10/IL-17 ratio can be used as prognostic markers for ulcerative colitis. This provides a theoretical basis for design of targeted treatment and prognosis assessment of the disease.