An HLA-associated nonresponsiveness to mellitin: a component of bee venom.

Previous work has demonstrated a close association between certain histocompatibility antigens and the gene that controls the IgE response to certain ragweed allergens. For example, there is a 90% association between IgE production to the short ragweed allergen, Amb a V, and an HLA class II allele. To assess whether these HLA linkages are specific for ragweed, we have investigated the association between HLA antigens and the capacity of individuals to mount a specific IgE response to melittin in patients with bee-venom allergy. Twenty-two subjects with bee-venom sensitivity, 22 healthy beekeepers without bee-venom allergy, and a normal population of 149 unselected individuals were studied. With serologic tissue typing and restriction fragment length polymorphism analysis, we have demonstrated a significant decrease in the HLA-DR4 and DQw3 alleles in subjects who are allergic to melittin compared to the control populations. There was also a negative association between the presence of HLA-DR4 and DQw3 alleles with the capacity of the individuals to mount an IgE response to phospholipase A2 (PLA2). The bee-venom sensitive subjects had a slightly lower titer of anti-PLA2 IgG when these subjects were compared to the bee-venom insensitive beekeepers. These results support the view that either HLA-DR or HLA-DQ has a protective role in controlling the IgE immune response. Lack of an IgE response to melittin or PLA2 is unlikely to be due to a failure to recognize allergen.