Abstract
The neonatal skin is central to early survival and immune development. Far from being a passive mechanical barrier, it integrates physical, chemical, and microbial defences that together protect the infant in the immediate postnatal period. In preterm infants, structural immaturity, reduced antimicrobial capacity, and altered microbial colonisation confer heightened vulnerability to infection and inflammation. At the same time, the neonatal period represents a critical window during which skin–microbe interactions shape tolerance and long-term immune trajectories. This review summarises recent advances in understanding the development of the skin barrier, antimicrobial and innate immune defences, and the role of commensals in immune programming. Translational opportunities for neonatal care are discussed, including skin protective practices, antisepsis, and emollient use that may reduce infection risk in the neonatal intensive care unit. Finally, we consider future directions in microbiome-informed and skin-centred strategies.
