Regulatory B cells (Bregs) are a subset of IL-10-producing B cells involved in the maintenance of tolerance and the restoration of homeostasis following inflammation. Although multiple subsets of IL-10-producing B cells exist in mice, the most widely investigated Bregs are splenic B10 cells. Mouse B10 cells have been characterized as CD19+CD5+CD1d+ cells, but these surface markers typically overlap with those of other B cell subsets. As a result, B10 cells in mice are commonly identified by their functional ability to produce IL-10 following stimulation with lipopolysaccharide or CpG oligonucleotides, phorbol myristate acetate (PMA), and ionomycin. In addition to IL-10, secretion of TGF-β and IL-35 may also contribute to Breg-mediated immunosuppression. In humans, several IL-10-producing Breg subsets have been identified in the peripheral blood. The counterpart of mouse B10 cells are human CD19+CD24+CD27+IL-10+ B10 cells. Other human B cell subsets with suppressive effects include an immature B cell population that has been characterized as CD19+CD24highCD38highIL-10+ and a second plasmablast population that is CD19+CD24highCD27intCD44highSyndecan-1/CD138+IL-10+.
B Cell Development Miniposter