A high molecular weight allergenic fraction of honeybee venom.

Chromatography of honeybee venom on Sephadex G-150 super fine revealed a high molecular weight (HMW) fraction that elutes prior to hyaluronidase (HYAL) and comprises 2% to 4% of the venom weight. HMW appears to exist in polymeric form, and the polymer which is present in greatest concentration has an estimated molecular weight of 105,000 D. The 12% nitrogen content of HMW suggests it may not be all protein. HMW is antigenically and enzymatically distinct from HYAL and phospholipase A2 (PHOS A). The acid phosphatase activity known to be present in honeybee venom was found in the HMW fraction. Since it reacts by RAST with the sera of most individuals known to be sensitive to honeybee venom, and releases histamine from the peripheral leukocytes of such individuals, its role as an allergen is confirmed. Since individuals react to different degrees to HMW, HYAL, and PHOS A, there does not appear to be a single principal allergen in honeybee venom.