Figure 7.

MyD88 is required for Btk-mediated autoimmune disease. (A) Absolute numbers of splenic germinal center B cells (GC; CD19⁺IgD⁻CD95⁺), Fol T helper cells (Tfh; CD3⁺CD4⁺CXCR5⁺PD1⁺ FoxP3⁻) and Fol T regulatory cells (Tfr; CD3⁺CD4⁺CXCR5⁺PD1⁺ FoxP3⁺). (B) Absolute numbers of splenic IgM⁺, IgG1⁺, and IgG2bc⁺ plasma cells (PC; CD11b⁻IgG1⁻IgGbc⁻IgM⁺CD138⁺, CD11b⁻IgG1⁺CD138⁺, and CD11b⁻IgG2bc⁺CD138⁺, respectively). (C) Serum concentrations of IgM, IgG1, and IgG2c, as determined by ELISA. (D,E) IFNγ, IL-6, and IL-10 expression in gated B cell fractions (D) and CD3⁺CD4⁺ T cell fractions (E) upon in vitro stimulation with PMA/ionomycin for 4 h in the presence of monensin. Symbols represent individual mice and bars indicate mean values. Graphs represent two to three individual experiments. (F) Representative pictures of serum IgM (upper panel) and IgG (lower panel) reactivity with HEp-2 cells and quantification of autoreactivity. Total number of mice analyzed are indicated within the pie charts; –, no staining; +/–, mild staining; +, moderate staining; ++, strong staining. CD19-hBtk and WT mice were 28–33 weeks old; ^*p < 0.05, ^**p < 0.01, ^***p < 0.001 by Mann–Whitney U-test.