Figure 5

OT preserves the capacity to activate the CD40 signaling pathway. (A) Representative histograms of STAT3 phosphorylation in Bregs (CD19⁺CD24^hiCD38^hi), naive B cells (CD19⁺CD24^intCD38^int) and memory B cells (CD19⁺CD24^hiCD38⁻) at 0 and 5 min after stimulation with CD40 mAb. (B), (C) and (D) display the percentage of increase of the median of fluorescence intensity (MFI) of pSTAT3 in Bregs, naive B cells and memory B cells after stimulation, respectively. (E), (F) and (G) show the fold increase in the percentage of pSTAT3-positive cells after stimulation in Bregs, naive B cells and memory B cells, respectively. (H) Representative zebra plot for one healthy individual showing the frequency of IL-10-positive cells after stimulation within the B-cell subpopulations studied. Purified B cells were stimulated for 48 h with plate-bound anti-CD40 mAbs plus soluble CD40L. Phorbol myristic acid and ionomycin were added for the last 5 h of culture. CD19⁺IL-10⁺ B cells were measured by intracellular cytokine staining. (I) IL-10 production by the B-cell subpopulations in four healthy individuals. Bar graphs indicate mean ± SEM percentages of Breg, naive and memory B cells that produced IL-10. OT group, n = 5; CR group, n = 10; Sta group, n = 17; HI group, n = 10. *p < 0.05.