Comparison of the allergenicity and antigenicity of yellow jacket and hornet venoms.

The immunologic properties of yellow jacket and hornet venoms were compared by measuring their reaction with rabbit antisera and human IgE and IgG antibodies. Anti-hornet venom rabbit serum showed precipitin bands unique to hornet venom and several bands crossreacting with yellow jacket venom. Anti-yellow jacket venom rabbit serum reacted with yellow jacket venom but failed to react with the hornet venoms. Most sera from patients who had had allergic reactions after vespid stings reacted with yellow jacket and hornet venoms in RAST analysis. A few sera reacted with only one of the venoms. RAST inhibition studies confirmed the crossreactivity of these IgE antibodies. The IgG antibody response of 14 patients was measured after yellow jacket venom immunotherapy. All had rising titers of yellow jacket venom-specific IgG. There was also an increase in the IgG antibody response measured with hornet venom in the majority of patients. The rise was significant with yellow hornet venom (p less than 0.02) but failed to reach significance with bald-faced hornet venom (p greater than 0.05). In IgG radioimmunoassay inhibition studies using yellow jacket venom-coupled discs, yellow jacket venom was considerably more potent than hornet venom. These studies indicate major crossreactivity between yellow jacket and hornet venoms. In this group of patients, yellow jacket venom appeared to be the primary allergen.