Autocrine stimulation of IL-10 is critical to the enrichment of IL-10-producing CD40hiCD5+ regulatory B cells in vitro and in vivo

摘要

IL-10-producing B (Breg) cells regulate various immune responses. However, their phenotype remains unclear. CD40 expression was significantly increased in B cells by LPS, and the Breg cells were also enriched in CD40hiCD5+ B cells. Furthermore, CD40 expression on Breg cells was increased by IL-10, CD40 ligand, and B cell-activating factor, suggesting that CD40hi is a common phenotype of Breg cells. LPS-induced CD40 expression was largely suppressed by an anti-IL-10 receptor antibody and in IL-10?/?CD5+CD19+ B cells. The autocrine effect of IL-10 on the CD40 expression was largely suppressed by an inhibitor of JAK/STAT3. In vivo, the LPS treatment increased the population of CD40hiCD5+ Breg cells in mice. However, the population of CD40hiCD5+ B cells was minimal in IL-10?/? mice by LPS. Altogether, our findings show that Breg cells are largely enriched in CD40hiCD5+ B cells and the autocrine effect of IL-10 is critical to the formation of CD40hiCD5+ Breg cells.