Fig. 2
Role of IL-10 in FcγRIIb expression on B cells and in vitro effect of purified IgG. FcγRIIb expression in response to anti-IgM stimulus was assessed in WT and IL-10−/− adult mice (a). Offspring from immunized or non-immunized IL-10−/− mothers were evaluated at 3 days of age or immunized with OVA in the neonatal period and evaluated at 20 days of age [20 (Im)]. The total IgE, anti-OVA IgG1 and anti-OVA IgM levels were determined by ELISA, and splenic B cell FcγRIIb expression was evaluated by flow cytometry. A representative histogram of FcγRIIb expression in each group is shown (b). Identical maternal and neonatal OVA immunization protocols were performed using IL-10−/− females and WT males, and splenic B cell FcγRIIb expression in IL-10−/+ offspring was evaluated by flow cytometry analysis (c). Similar maternal and neonatal immunization protocols were performed using Dp, and the splenic B10 cell numbers and B cell FcγRIIb expression in offspring were evaluated by flow cytometry (d). Offspring splenocytes were cultured for 7 days with 20 µg/mL OVA or 100 µg/mL purified IgG from non-immunized (NO IgG) or immunized mothers (IM IgG) with or without FcγRII/III-blocking Ab. The percentage of B10 cells was evaluated by flow cytometry (e). *P ≤ 0.05 compared with the offspring of the respective non-immunized mothers. # P ≤ 0.05 compared with the respective result from the sample without FcγR-blocking Ab