Ontogeny of mucosal immunity and aging

Abstract

The mucosal immune system begins development in utero at as early as 40 days gestation, and by the time of birth all components of the system are in place and have the potential to effectively respond to antigenic challenge. In early childhood development is influenced by many factors such as maternal stress, feeding practices, the mucosal microbiome, vaccination, nutritional status, infection, and the host of environmental antigens encountered. Mucosal immune function reaches that observed in adults around the age of five to seven years. There is some evidence to suggest that developmental profiles of mucosal immunity in childhood may be related to disease susceptibility in later life, but further studies are required. In adulthood there are a number of factors that are able to modify and compromise mucosal immunocompetence. These include nutritional status, infection, and stress, both psychological and physical. In the elderly the acquired mucosal immune response remains competent, although there is some loss of innate defenses.