Increased circulating Th17 cells and elevated serum levels of TGF-beta and IL-21 involved in human non-segmental vitiligo development (P3141)

Abstract

Abstract Although it is widely believed that non-segmental vitiligo (NSV) results from the autoimmune destruction of melanocytes, the detailed immune mechanisms remain poorly understood. Th17 cells, a subset of CD4+ helper T cells, have been identified to be implicated in a variety of human autoimmune diseases. To comprehensively evaluate the role of Th17 cells and the pathways driving these T cell differentiations in NSV, we had compared the frequencies of peripheral blood Th17 cells and other IL-17 producing T cells by flow cytometry between 42 active NSV patients with 45 race-, gender- and age-matched healthy control subjects. Serum levels of IL-17A and Th17 cell differentiation related cytokines including TGF-beta1, IL-6, IL-23, IL-22 and IL-21 were detected by ELISA. Our results showed the increased circulating Th17 cell frequencies and elevated serum IL-17A, TGF-beta1 and IL-21 levels in NSV patients. Further more, the increased Th17 cell frequencies are positively correlated with serum TGF-beta1 levels and the body surface area (BSA) in NSV patients. These results indicate the involvement of Th17 cells in the development and progression of NSV, and more importantly, our data highly suggest that elevated serum TGF-beta and IL-21 could contribute to enhanced Th17 cell differentiation in NSV.