Allergens in bee venom II. Two new high molecular weight allergenic specificities.

Two new allergenic specificites were detected in honeybee venom and the two corresponding protein substances isolated by gel filtration, immunoadsorption, and ion exchange chromatography. The first of these, allergen B, has a molecular weight ranging from 49,000 to more than 200,00 d and can be recognized by rabbit and guinea pig antisera as well as by human reaginic sera using the radioallergosorbent test (RAST). Allergen B gives a single line in immunodiffusion distinct from hyaluronidase, phospholipase A, melittin, and the other high molecular weight substances described and gives a single band at 49,000 d in sodium dodecyl sulfate (SDS) polyacrylamide gel. The second substance, allergen C, has a molecular weight of 105,000 d and was separated from allergen B by immunoadsorption with insoluble antibody. Allergen C was shown to be distinct from the other sustances in bee venom by immunodiffusion with animal antisera. One human reaginic serum was monospecific for allergen C. Two other minor components of 86,000 and 71,000 d are present in bee venom; their allergenic activities are unknown. The two specifities, B and C, comprise most of the reactivity of the previously described Sephadex G-75 fraction 1 and clearly are important allergens, reacting with 98% of sera from bee venom-allergic individuals.