Perinatal influences on IgE responses.

IgE-mediated (atopic) allergy depends on the production of IgE antibodies to normally harmless substances. It is associated with other immunological abnormalities, particularly defects in the T lymphocyte system, and is now generally considered to be a manifestation of IgE-suppressive immunodeficiency. Experiments with adult laboratory animals have revealed the existence of an IgE-selective immunoregulatory system and great efforts are being made to understand the mechanisms by which this system operates, to compensate for, or correct, the deficiency of atopic individuals. However, since allergy is often a problem of childhood one might reasonably ask if experiments with adult animals are a wholly appropriate approach to the problem. Rats were used to explore factors influencing the development of IgE regulation during early life, when the immunological apparatus differs intrinsically from that of mature animals. The results of these experiments, which have shown profound IgE-suppressive effects of maternal antibody and of neonatally ingested antigen, are reviewed with the aim of stimulating research on this topic in man.