The impact of the N-glycan on the in vivo transport of monoclonal antibodies through the placenta. To investigate the effect of N-glycan on IgG transport, a total of 40 µg SZ21, NGM-SZ21, or isotype-matched (nonplatelet-binding) IgG were injected in age-matched pregnant female BALB/c mice at day 17 of gestation. Blood samples from newborn pups were collected within 8 hours after birth. (A) Binding of transported antibodies is shown. In SPR, similar antibody binding to GPIIb-IIIa from HPA-1aa platelets was detected in the blood of pups whose mothers were injected with either SZ21 or NGM-SZ21. No relevant antibody binding was detected using the blood of the control pups. (B) Quantification of circulating antibodies is shown. An equal amount of SZ21 and NGM-SZ21 (8.9% and 8.7%, respectively, P = .58) was transported from maternal (black bars) into neonatal (white bars) circulation at the end of the pregnancy. This figure shows data from 3 different experiments.