POSSIBLE DUAL ROLE OF ANTIIDIOTYPIC ANTIBODIES IN COMBINED PASSIVE AND ACTIVE IMMUNOTHERAPY IN HONEYBEE STING ALLERGY

Background: Passive infusion of beekeepers' plasma was shown to protec t patients against systemic reactions occurring during active immunoth erapy by mechanisms still to be clarified. If is tempting to speculate that anti-idiotypic antibodies could play a role because they are fou nd in beekeepers' plasma and are involved in the regulation of IgE syn thesis. Methods: In this report we studied the effects of passive infu sion of a beekeeper's plasma rich in anti-idiotypic antibodies to a pa tient who experienced systemic reactions to honeybee venom. Results: W e reported, during the days after the infusion, a decrease of clinical sensitivity to the honeybee venom. Indeed, the patient tolerated a cu mulative dose of 280 mu g of venom without adverse reactions. We also observed decreases in skin mast cell and in basophil sensitivity. Afte r the plasma infusion, a modified rush immunotherapy with honeybee ven om was initiated in our parient. In the following 76 weeks, increased levels of anti-idiotypic antibodies in the serum of the patient were a ssociated with a diminution. of specific antibodies (IgG and IgE) to h oneybee venom. Conclusion: These results suggest a dual role of anti-i d in our combined protocol of passive and active immunotherapy: an imm ediate action on clinical sensitivity along with a decrease of skin ma st cell and basophil sensitivity and an immunoregulatory role on speci fic antibody production.