VEGF increases splenic B cells via VEGFR-1 and VEGFR-2 has opposite effect. The 8- to 10-week-old Balb/c mice were given PBS or VEGF receptor agonists for 28 days as described in Figure 1. (A) The representative spleens from PBS, VEGF-A, VEGFR2-sel, and VEGFR1-sel mice (from left to right). (B) The total splenocytes of spleens from the pump mice. (C) The splenocytes were analyzed for expression of CD19. The representative FACS histograms were shown. (D) Total number of B cells (CD19⁺) in spleens. (E) 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. Total number of B cells (CD19⁺) in spleens is shown. The data (mean ± SEM, n ≥ 5) repeat 2 times. All of the other data (mean ± SEM, n ≥ 3) repeat 3 times. *P < .05; **P < .01.