A COMPARATIVE-STUDY OF IGG SUBCLASS ANTIBODIES IN PATIENTS ALLERGIC TO WASP OR BEE VENOM

IgG1 and IgG4 antivenom antibody responses were compared in groups of patients who had experienced systemic reactions to wasp (Vespula spp.) or bee stings. Pretreatment serum IgG4 antibody levels were low in bo th groups, but IgG1 antibodies were significantly raised in bee-allerg ic patients (P<0.002), probably reflecting their greater exposure to s tings than wasp-reactive patients. No direct or indirect relationships were found, in untreated bee or wasp patients, between IgG1, IgG4, or IgE antibody levels and the severity of a patient's last systemic rea ction to a sting. After a la-week course of venom immunotherapy (VIT), IgG1 antibodies increased significantly only in wasp-sensitive patien ts (P<0.001), although both groups responded with marked increases in venom-specific IgG4 (P<0.01). Wasp-allergic subjects who responded to VIT with high production of specific IgG4 showed the greatest increase s (pre- to post-VIT) in IgE antibodies (P<0.05). This group also demon strated a direct correlation (P<0.05) between post-VIT levels of IgE a nd IgG1 antibodies, a finding contrary to an IgE-immunoregulatory role for IgG1. High levels of venom-specific IgG1 alone, or in combination with IgC4, were not protective in three patients who suffered repeate d adverse reactions to bee VIT, showing that absolute levels of IgG su bclass antivenom antibodies are not reliably indicative of clinical re sponsiveness in individual patients.