Active immunization of rabbit with gamma irradiated Russell's viper venom toxoid

Russell's viper venom detoxified by gamma (gamma)-radiation (100 kR or 200 kR) was used as a toxoid for active immunization of rabbits following a short or long schedule of immunization without any adjuvant. Effective neutralization of venom toxin by immune sera of rabbits was observed with both schedules. Sera of rabbits immunized with 100 kR irradiated venom toxoid (100 kR toxoid antisera) were more potent than 200 kR toxoid antisera. The presence of antibody in the immune sera was detected by immunoelectrophoresis. The effect of gamma-radiation on some enzymes and venom protein profiles was studied. Phosphodiesterase, protease and hyaluronidase were inhibited by radiation though phospholipase A activity remained unaffected. Radiation did not produce any gross change in the protein profile of crude viper venom. Phosphodiesterase and protease activities of viper venom were neutralized more effectively by 100 kR toxoid antisera in the short schedule than in the long schedule of immunization.