Rac2^+/E62K mice recapitulate cytopenias, superoxide production, and increased neutrophil F-actin content seen in patients. (A) Peripheral blood cells from Rac2^+/+ and Rac2^+/E62K mice stained for lineage markers (n = 4 each group). Top, from left: CD3⁺ T cells, CD3⁺CD4⁺ T cells, CD3⁺CD8⁺ T cells, and CD20⁺ B cells (P value calculated using Student t test with Welch correction). (B) Splenic cell populations from Rac2^+/+ and Rac2^+/E62K mice identified by noted markers. Two-way ANOVA with Sidak multiple comparison test was used to determine significance. (C) Splenic T-cell subsets from Rac2^+/+ and Rac2^+/E62K mice identified by noted markers. Two-way ANOVA with Sidak multiple comparison test was used to determine significance. (D) Superoxide production after addition of fMLF in bone marrow neutrophils from Rac2^+/+ (black lines) and Rac2^+/E62K mice (red lines). Results combined from 2 independent experiments. (E) Phalloidin staining for F-actin in mouse bone marrow neutrophils from Rac2^+/+ and Rac2^+/E62K mice (n = 4 each group). Results combined from 2 independent experiments.