Reduced cellularity in the BM, spleen, and LN of flt3L−/− mice.

BM was isolated from the 2 femurs of each mouse (n = 25 mice) and cellularity determined. Spleens (n = 14), LN (n = 7), and thymi (n = 11) were isolated, single-cell suspensions prepared, and cell counts were performed. LN counts represent cellularity from 6 LN per mouse (2 inguinal nodes plus 2 brachial nodes plus 2 axillary nodes). Data are presented as the mean ± SD. *P < .0001 for BM, P = .0046 for spleen, and P = .0053 for LN.