VEGF promotes bone marrow B-cell development via VEGFR-1 and VEGFR-2 has the opposite effect. (A) Flow cytometric analysis of bone marrow cells expressed CD43 and B220. The representative FACS plots were shown. The first plot is the isotype control. (B) The proportion of pre-B/pro-B (left) and the percentage of B-cell subsets (right) in total bone marrow cells: pro-B cells (CD43⁺B220⁺) and pre-B cells (CD43⁻B220⁺). The data (mean ± SEM, n ≥ 3) repeat 3 times. (C) Balb/c mice were given PBS treated with rat IgG, or rhVEGF-treated rat IgG, anti-R1 or anti-R2 as described in Figure 1C. The proportion of pre-B/pro-B (left) and the percentage of B-cell subtypes (right) in total bone marrow are shown. The data (mean ± SEM, n ≥ 5) repeat 2 times. *P < .05; **P < .01.