Immune responses during pregnancy and the development of allergic disease.

It is now established that allergen exposure in the first few months of life is important in the development of specific allergic sensitisation (1, 2). Furthermore, the immune response of infants born to families with a strong history of allergic disease is relatively immature at birth in comparison to infants with no family history of allergies, with reduced production of Interferon-gamma (IFN-gamma) (3-5) and lower levels of T cell activation and memory (6). It therefore seems logical that the interaction of these two factors must be important in the ontogeny of allergic disease.