‘Layered immunity’ and the ‘neonatal window of opportunity’ – timed succession of non‐redundant phases to establish mucosal host–microbial homeostasis after birth

The intricate host–microbial interaction and the overwhelming complexity of the mucosal immune system raise the question of how this system is initially established. Here, we implement the concept of the ‘postnatal window of opportunity’ into the model of a ‘layered immunity’ and formulate a concept of a timed succession of non‐redundant phases during postnatal immune development. This concept explains how host–microbial immune homeostasis is established after birth and we outline and discuss the possible influence of external factors and conditions. Open in a separate window