Fig. 3

Sex differences in the production of TNF-α by B cells following stimulation with a TLR7 and TLR9 agonist. A A representative flow cytometry analysis to identify TNF-α positive B cells in an unstimulated condition (left), after 20 h of stimulation with the TLR7 (CL097) agonist (middle) and the TLR9 agonist (CpG (ODN 2216)) (right) is shown. The assessment of the percentages of TNF-α positive B cells is shown in an unstimulated condition, after stimulation with the TLR7 agonist (CL097) or the TLR9 agonist (CpG (ODN 2216)) in a group of 22 healthy individuals. No increase of TNF-α positive B cells was detected upon TLR7 stimulation. The percentage of TNF-α positive B cells increased significantly upon stimulation with the TLR9 agonist compared with unstimulated B cells (p < 0.0001; two-tailed t test; women n = 11, men n = 11). B Left figure: levels of TNF-α were measured in the supernatant of isolated B cells after stimulation with a TLR9 agonist CpG (ODN 2216) using Luminex multiplex technology. The fluorescence intensity of TNF-α is illustrated in the dot plots in women (pink dots) and men (blue dots). B cells of women produced significantly higher levels of TNF-α than B cells of men after stimulation of TLR9 (p = 0.02; two-tailed t test; women n = 9, men n = 9). Right figure: TNF-α positive B cells were determined ex vivo from female or age-matched male donors using FlowJo software. Women (pink dots) showed a significantly higher percentage of TNF-α producing B cells in response to stimulation with CpG (ODN 2216) compared with men (blue dots) (p = 0.01; two-tailed t test; women n = 11, men n = 11)