This chapter examines the influence of allergen exposure during development. Exposure to allergen can occur during fetal, neonatal, and juvenile years, which are critical times for immunological and structural development of the lung. Exposure of the fetus to allergens inhaled by the mother during pregnancy can result in its sensitization to those allergens. The interaction of environment and genetic background during in utero life of a human infant may determine the future allergic status of the child and adult. The exposures that occur in the first months of life are very likely crucial to phenotypic development of the child and subsequently the adult. Thus, exposures to allergens, such as pollens, may facilitate future development of allergic disease, especially in the atopy prone genotype. However, exposure to certain other antigens during this critical time of development can influence or modulate the immune response. Several infectious diseases are thought to have a role in either facilitating development of allergic sensitization to inhaled allergen during the neonatal period or subverting the allergic response.
ASJC Scopus subject areas