Figure 5
Breastfeeding-induced protection by ovalbumin (OVA)-exposed sensitized mothers requires neonatal Fc receptor (FcRn) but not FcγRIIb. (a) Levels of OVA–IgG1 immune complexes in pups sera. Wild-type (empty bars) or FcRn-deficient (black bars) C57BL/6 pups were breastfed by unexposed or OVA-exposed sensitized mothers and analyzed 14 days after birth for the presence OVA–IgG1 immune complexes in serum by enzyme-linked immunosorbent assay (ELISA). Data show the mean±s.e.m. of values obtained in one representative experiments with n=6 mice per group. Wild type (b–d), FcRn-deficient (e–g), or FcγRIIb-deficient (h–j) C57BL/6 pups were breastfed by unexposed (dark gray bars) or OVA-exposed (black bars) sensitized mothers. Non-sensitized mice challenged with OVA were used as controls (hatched bars). Data show cell number and eosinophils frequency in bronchoalveolar lavage (BAL) fluids (b, e, and h), serum levels of OVA-specific IgG (c, f, and i), and levels of IL-5 and IL-13 secreted by lung cells when incubated with OVA (d, g, and j). Data are expressed as mean±s.e.m. of five experiments for wild-type C57BL/6 and two experiments for FcRn-deficient and FcγRIIB-deficient mice with n=6–8 mice per group in each experiment. ****P<0.0001; *P<0.05; NS, P>0.05.
