CD19<sup>+</sup>CD24<sup>hi</sup>CD38<sup>hi</sup> B Cell Dysfunction in Primary Biliary Cholangitis
Qubo Chen, Lanmin Lai, Xiaoling Chi, Xinyi Lu, Huaxian Wu, Jing Sun, Weilin Wu, Li Cai, Xuan Zeng, Chuyang Wang, WeiCheng Chen, Anping Peng
Abstract
CD19 + CD24 hi CD38 hi B cells are immature transitional B cells that, in normal individuals, exert suppressive effects by IL-10 production but are quantitatively altered and/or functionally impaired in individuals with various autoimmune diseases. Primary biliary cholangitis (PBC), an autoimmune disease, clinically presents as chronic cholestasis and nonsuppurative destructive cholangitis. A role for CD19 + CD24 hi CD38 hi B cells in PBC is unknown. This study investigated the frequency and functional variation of circulating CD19 + CD24 hi CD38 hi B cells in PBC patients. Flow cytometry was employed to quantify the percentage of CD19 + CD24 hi CD38 hi B cells in peripheral blood samples. Correlations between CD19 + CD24 hi CD38 hi B cells and routine laboratory parameters were assessed. Levels of IL-10, TNF- α , IL-6 and IL-12, and Tim-1 in CD19 + CD24 hi CD38 hi B cells from PBC patients were analyzed. The effect of CD19 + CD24 hi CD38 hi B cells on CD4 + T cell differentiation was evaluated. The percentage of CD19 + CD24 hi CD38 hi B cells in PBC patients was significantly higher than in healthy controls and was positively correlated with liver cholestasis. After activation by anti-B cell receptor and CpG, the production of IL-10 was decreased and the production of IL-6 and IL-12 was increased in CD19 + CD24 hi CD38 hi B cells from PBC patients. Moreover, Tim-1 levels were significantly downregulated in CD19 + CD24 hi CD38 hi B cells from PBC patients. Coculture showed that PBC-derived CD19 + CD24 hi CD38 hi B cells were less capable of CD4 + T cell inhibition, but promoted Th1 cell differentiation. In conclusion, PBC patients have expanded percentages, but impaired CD19 + CD24 hi CD38 hi B cells, which correlate with disease damage. In PBC patients, this B cell subset has a skewed proinflammatory cytokine profile and a decreased capacity to suppress immune function, which may contribute to the pathogenesis of PBC.