Table S1 - Activated Peritoneal Cavity B-1a Cells Possess Regulatory B Cell Properties

Similarities and equalities between regulatory B cells and B-1a cells. 1 CD19 is a positive BCR regulator; BCR signalling is decreased in CD19−/− mice, while it is vice versa increased in hCD19Tg that overexpress (human) CD19. hCD19Tg mice have increased amounts of B-1a cells, but decreased amounts of B-1b cells. CD19−/− mice vice versa, possess increased amounts of B-1b cells, but lack B-1a cells [5], [6]. 2 CD22 is a negative BCR regulator; and it's absence results in increased BCR signaling [22]. 3 The regulatory B cells in these articles possess a phenotype other than the CD5+ CD1dhi B10 cells; there are instead: MZ (CD1dhi) Bregs [14]/CD19+ IL-10+ CD1dhi CD5+ CD21hi CD23+ IgD+ IgMhi [15]. 4 This article demonstrates that MZ B cells (and not FO B cells) can gain regulatory B cell roles after BAFF treatment. Splenic B-1a cells were not investigated. (PDF)