Pak2-KO spleen MDSCs are more proliferative than WT cells Freshly isolated splenocytes from mice reconstituted with Pak2-KO or WT BM were stained for CD11b, Gr1, and intracellular Ki-67. (A) MFI of Ki-67 in gated CD45.2⁺CD11b^highGr1^high and CD11b⁺Gr1^low populations is shown. (B) Representative flow histograms are shown. Representative data from 2 experiments with 3 to 6 mice per genotype are shown. ***P < .001.