Fig. 3.

Effect of inhibition of the PLCγ pathway on IL-7-dependent B cell functions. a, b PLCγ pathway inhibition impairs IL-7-dependent B cell production. Lin⁻ BM cells from wild-type mice were cultured on OP9 cells in the presence of IL-7 for 1 day and then the cells were treated with DMSO, CP690550, U73122, or edelfosine. The cells were stained with anti-B220 and anti-Mac-1. Numbers indicate percentages of B220⁺ and Mac-1⁺ cells in the gated live cells (a) and bar graphs show the percentages and numbers of B220⁺ and Mac-1⁺ cells (b). c–e PLCγ pathway inhibition impairs IL-7-mediated proliferation but not survival of in vitro-expanded B cell progenitors. BM cells from Rag1-deficient mice were cultured in the presence of IL-7 for 7 days to derive B cell progenitors. These B cell progenitors were then cultured without IL-7 (medium) or with IL-7 plus DMSO, CP690550, U73122, or edelfosine. Cell proliferative responses were determined by [³H] thymidine incorporation (c), cell-cycle analysis was performed by PI staining (d), and cell survival was measured by TUNEL staining (e). f, g PLCγ pathway inhibition impairs IL-7-mediated proliferation and survival of unexpanded B cell progenitors. B220⁺IgM⁻IL-7R⁺ B cell progenitors were sorted from wild-type mice and cultured without IL-7 (medium) or with IL-7 plus DMSO, CP690550, U73122, or edelfosine. Cell-cycle analysis was performed by PI staining (f) and cell survival was measured by TUNEL staining (g). Error bars show ± SEM. Data shown are obtained from or representative of 3 (a, b), 6 (c), 7 (d, e), and 5 (f, g) independent experiments