Interleukin-10 (IL-10) response profiles and the timing and nature of environmental exposures may contribute to the development of allergic sensitization during early childhood.

Cord blood obtained from infants enrolled in the COAST project were stimulated in vitro with phytohemagglutinin (PHA) for 24 hours, and supernatant fluids were analyzed for IL-10 by ELISA. Values for IL-10 secretion were compared to allergen-specific IgE results evaluated at age 2 years for the following antigens: D. farinae, D. pteronyssinus, Alternaria alternata, dog dander, cat dander, milk, egg, peanut, and soy.

Infants who were sensitized to any aeroallergen had significantly lower levels of IL-10 than those that were not (median 89.7 vs 107.4 pg/ml, p=0.04). When individual allergens were evaluated, IL-10 secretion profiles were not associated with sensitization to mites or Alternaria, but were significantly lower with both dog (median 73.7 vs 107.0 pg/ml, p=0.001) and cat (median 71.4 vs 107.3 pg/ml, p=0.007) sensitization. IL-10 secretion profiles were not associated with the development of food allergen sensitization (median 97.9 vs 104.6 pg/ml, p=0.18).

Reduced IL-10 responses at birth are associated with increased risk for the development of sensitization to some, but not all, allergens following early life exposures.