Interleukin-10 production by B cells is regulated by cytokines, but independently of GATA-3 or FoxP3 expression.

ABSTRACT

The knowledge of mechanisms of regulation of IL-10 production by B cells remains still very limited. We show here that highly purified mouse B cells stimulated with LPS produce significant levels of IL-10, but Bregs in our model do not express detectable level of either Foxp3 or GATA-3. Nevertheless, IL-10 production by B cells is regulated by cytokines. In activated B cells, IL-10 production was significantly enhanced by IFN-γ and decreased in the presence of IL-4 or TGF-ß. These findings are in sharp contrast with the observations in T cells, where IL-10 production correlates with GATA-3 or FoxP3 expression, and the cytokines regulate IL-10 production in a reverse manner than in activated B cells. These results thus show that the production of IL-10 by Bregs is regulated by cytokines independently of the expression of GATA-3 and FoxP3, which is clearly different from GATA-3-dependent IL-10 production by activated Th2 cells and FoxP3 expression in IL-10-producing Tregs.