EμB29-Btk gene therapy restores central and peripheral B-cell development. PB, BM, spleen, and peritoneal cells from LV-treated mice and mock controls were stained for surface markers and analyzed by flow cytometry to identify B-cell subsets (supplemental Figure 2, gating strategy). (A) PB cells were first gated on live and CD11b⁻ populations and then analyzed for B220, IgM, and IgD expression. FACS plots show representative mice from WT mock (n = 7), KO mock (n = 8), MOI 3 (n = 3), and MOI 15 to 25 (n = 12) experimental groups. (B-E) Total cell numbers in each B-cell subset were determined for BM, spleen, and peritoneal cavity. In bar graphs, KO data include both unmanipulated and mock-transplanted animals. Data represent 4 independent experiments. P values compare EμB29-Btk and KO groups: ***P < .001; **P = .001-.01; *P = .01-.05.