Correlation between lymphocyte responses and immediate hypersensitivity to purified allergens.

Seventy-nine unrelated subjects were selected for high allergic sensitivity to ragweed and/or grass pollens. Sensitivities to ragweed antigens E and Ra5 and rye grass group 1 were measured by intradermal skin testing and by histamine release in vitro. Lymphocyte responses were determined by incorporation of 3H-thymidine in vitro in the presence of antigen. Skin-test and histamine-release sensitivities were significantly correlated with lymphocyte response in the case of antigen E, but not for group 1 and Ra5. In addition, lymphocyte response to antigen E was significantly correlated with total serum IgE level. Six antigen E-sensitive individuals had marked delayed, but no immediate, reactions to Ra5 and almost all showed lymphocyte responses to Ra5. We conclude that immediate sensitivity and lymphocyte responses of allergic individuals to antigen E are significantly correlated, and that lymphocyte responses and delayed reaction to an antigen without immediate sensitivity or IgG antibody are possible even in allergic subjects.