(D) Absolute numbers of lymphocytes subpopulations in the bone marrow, thymus, and spleen. B cell development in the bone marrow was assessed by FACS analysis for surface expression of: B220+CD43+CD19−IgM−IgD− (pre-pro B); B220+CD43+CD19+IgM−IgD− (pro B); B220+CD43−CD19+IgM−IgD− (pre B); CD19+IgM+IgD− (immature); CD19+IgM+IgD+ (mature). T cell development in the thymus was assessed by FACS analysis for surface expression of: CD4−CD8− (double negative, DN); CD4+CD8+ (double positive, DP); CD4+CD8− (CD4 single positive, SP); CD4−CD8+ (CD8 SP). Splenic B cell populations were assessed by FACS analysis for surface expression of: B220+CD21+CD23+ (follicular B cells, FOB); B220+CD21+CD23low (marginal zone B cells, MZB). Each symbol represents an individual mouse. Horizontal bars indicate mean values. Two-tailed Mann-Whitney test, ns = not significant, *P < 0.05, and **P < 0.01. 