Limited ability of recombinant Hymenoptera venom allergens to resolve IgE double sensitization.

IgE antibodies against cross-reacting carbohydrate determinants (CCDs) are speculated to be one of the major causes (in addition to dual sensitization to and/or cross-reactivity between homologous venom proteins) of the in vitro double sensitization observed between honeybee (HB) and yellow-jacket (YJ) venom extracts.1 Furthermore, because IgEs against CCDs lack biological activity, they were thought to be responsible for the lack of in vitro IgE discrimination between clinically apparent allergy and clinically irrelevant sensitization (the majority of venom extract double-sensitized [DS] patients have a clinically apparent allergy to only one venom).