Humoral and cellular immune response of the rat to immunization with bee venom.

Lewis rats were immunized with bee venom allergen in Freund's complete adjuvant (FCA) or with FCA only. Animals immunized with bee venom developed specific IgG antibodies but no specific IgE antibodies were detected. Lymphocytes from lymph nodes when cultured with antigen in vitro showed an increased stimulation index from day 17 onwards. A concomitant augmentation of T suppressor cells was observed; the T helper/T suppressor cell ratio declined from 4.5:1 before immunization to 1:1 from day 5 onwards.