Fig. 2

Sex differences in the percentage of IRF5 positive B cells ex vivo following TLR7 and TLR9 stimulation. Percentages of IRF5 positive B cells were defined by Flow Cytometry with the aid of an isotype control. Upper row: percentages of IRF5 + CD20 + B cells are shown in an unstimulated condition and after 20 h of stimulation with a TLR7 agonist (CL097) and a TLR9 agonist (CpG (ODN 2216)). Percentages of IRF5 positive B cells increased significantly after TLR7 stimulation (p < 0.0001) and after TLR9 stimulation (p = 0.0002; two-tailed t test; women n = 11, men n = 11). Lower row left: women (pink dots) showed significantly higher percentages of IRF5 positive B cells than men (blue dots) after 20 h of TLR7 stimulation (p = 0.03; two-tailed t test; women n = 11, men n = 11). Lower row right: women (pink dots) showed significantly higher percentages of IRF5 positive B cells than men (blue dots) after 20 h of TLR9 stimulation (p = 0.02; two-tailed t test; women n = 11, men n = 11)