Lack of GILZ develops lymphocytosis in a B-cell autonomous fashion. (A-D) Frequency (left) and number (right) of B220⁺ cells in BM (A), PB (B), pLN (C), and Spl (D) isolated from 8- to 12-week-old WT and gilz CD19-KO mice (n = 7/8). (E) Frequency (left) and number (right) of B220⁺CD5⁺ cells in PB isolated from 8- to 12-week-old WT and gilz cKO mice (n = 7/8). (F-G) Frequency (on left) and number (on right) of B1a cells in spleen (F) or PC (G) isolated from 8- to 12-week-old WT and gilz cKO mice (n = 6/8). (H) Spleen histologic phenotype of 8- to 12-week-old WT and gilz KO mice assessed by H&E staining. Scale bars represent 100 µm; original magnification ×20. (I) Immunohistochemical analyses show that the number of CD45R/B220⁺ lymphocytes in spleen is increased in gilz KO compared with WT mice. Scale bars represent 100 µm; original magnification ×20. Graphs represent mean ± SEM. Data are from 2 independent experiments. *P < .05, **P < .005, ***P < .0005.