Fig. 1

Testosterone regulates splenic B cell number. a Representative plots of CD19⁺CD93⁺ transitional B cells (tB) and CD19⁺CD93^– mature B cells (matB) in the spleen from male control (Pgk-Cre⁺) and general androgen receptor knockout (G-ARKO) mice. b Total CD19⁺ B cells in the spleen in control (n = 10) and G-ARKO (n = 9) mice. c Total CD19⁺ B cells in the spleen in castrated (ORX) control and G-ARKO male mice treated with placebo (P) or testosterone (T) (25 μg/day) for 4 weeks (Control ORX P, n = 6; Control ORX T, n = 7; G-ARKO ORX P, n = 5; G-ARKO ORX T, n = 6; P-value from Kruskal–Wallis test followed by Mann–Whitney test). d % B1a (CD19⁺IgM⁺CD43⁺CD5⁺) and B1b (CD19⁺ IgM⁺CD43⁺CD5^–) cells in peritoneal fluid from control and G-ARKO male mice, n = 9/group. e–j CD19⁺ B cells were divided into subpopulations; graphs show transitional T1 (CD19⁺CD93⁺IgM⁺CD23^–) B cells (e), transitional T2 (CD19⁺CD93⁺IgM^hiCD23⁺) B cells (f), transitional T3 (CD19⁺CD93⁺IgM^loCD23⁺) B cells (g), follicular (FO) (CD19⁺CD93⁺CD21^intCD23⁺) B cells (h), marginal zone (MZ) (CD19⁺CD93⁺CD21^hiCD23^–) B cells (i), and B1 (CD19⁺CD43⁺) B cells (j) in the spleen in control (n = 10) and G-ARKO (n = 9) mice. k Sections of spleens from control and G-ARKO male mice. green, B cells (B220); red, T cells (TCRβ); and blue, metallophilic macrophages (MOMA/CD169). Scale bar = 500 μm. l–n Number of follicles per section (l) and mean B cell area (m) and mean PALS area (n) per follicle in spleen sections from control and G-ARKO mice, n = 4/group. o Total IgG levels in serum from control (n = 22) and G-ARKO (n = 19) mice. p IgG autoantibodies against DNA in control (n = 23) and G-ARKO (n = 18) mice. All bars indicate means; circles represent individual mice. *P < 0.05, **P < 0.01, ***P < 0.001 (Mann–Whitney test unless otherwise specified)