A. Representative FACS panel showing the percentile of B220 and CD117 positive pro B cells; B220+, CD25+ Pre-B cells; the B220+, IgMhi recirculating B cells and the B220 intermediate, IgM bright immature B cells in the bone marrow from the control Stim1f/+, Stim2 f/+, mb1Cre+ and the DKO Stim1 f/Δ, Stim2 f/f, mb1Cre+ mice. B. Representative FACS panel showing the B220 positive AA4.1 negative immature B cells and B220 positive, AA4.1 positive mature B cells; the transitional T1, T2, T3 B cells as well as the CD23 dull, IgM positive marginal zone (MZ) Bells and CD23 bright, IgM positive mature B cells in the spleen of control and Stim 1&2 DKO mice. C. B1 B cells in the peritoneal cavity and germinal center B cells in Peyer's patch from control and Stim 1&2 DKO mice. D. Absolute number of pro-B, pre-B, immature B and recirculating B cells in the bone marrow of control and Stim1&2 DKO mice. E. Percentile of Total B cells, Immature B cells, marginal zone (MZ) B cells and follicular (FO) B cells in the spleen of control and Stim1&2 DKO mice.