Transplacental antibody perfusion in the development of the newborn passive immunity: A literature review

Reducing infant mortality resulted from infections, particularly among premature infants, is a major public health concern. This fact emphasises the significance of transplacental transfer of maternal antibodies, including immunoglobulin G (IgG), to develop passive immunity and protect newborns from infections. The aim of this study was to summarise current findings on the mechanisms and factors affecting transplacental transfer of IgG and their role in the developing passive immunity in newborns. This review provided a systematic analysis of the scientific literature, including studies on the morphofunctional features of the placenta, the mechanisms of transplacental IgG perfusion, and their impact on fetal and neonatal immunological protection. The study supported the fact that IgG served a crucial function in the development of passive immunity in newborns, crossing the placental barrier and providing protection against infections in the early stages of life. As evidenced, the efficiency of transplacental IgG transfer varied depending on gestational age, with lower transfer rates in premature compared to full-term infants. The results demonstrated that different IgG subclasses (IgG1, IgG3, IgG4, and IgG2) were transferred across the placenta with varying efficiency, the fact associating with their affinity for the Fc receptor on the placenta. Infections and hypergammaglobulinemia in mothers were proved to affect transplacental IgG transfer, highlighting the need to monitor the infectious status of pregnant women to optimise neonatal protection. Maternal vaccination at specific stages of pregnancy was found to significantly increase IgG levels in the newborn’s blood, contributing to improved passive immunity and reducing the risk of infectious diseases in infants. The study results can be introduced into clinical practice to optimise vaccination strategies for pregnant women and develop personalised approaches for preventing infectious diseases in newborns, especially among premature neonates