Immunization with native and cobalt 60-irradiated Crotalus durissus terrificus venom in swiss mice: assessment of the neutralizing potency of antisera

Abstract

ELISA was used to evaluate, follow, and compare the humoral immune response of Swiss mice during hyperimmunization with natural and Cobalt 60-irradiated (60Co) Crotalus durissus terrificus venom. Potency and neutralization were evaluated by in vitro challenges. After hyperimmunization, immunity was observed by "in vivo" challenge and the side effects were assessed. The animals immunization with one LD50 of the venom was on days one, 15, 21, 30, and 45, when blood samples were collected; the challenges occurred on the 60th day. Results showed that ELISA was efficient in evaluating, following, and comparing mouse immune response during hyperimmunization. Serum titers produced with natural venom were similar to those produced with irradiated venom. Immunogenic capacity was maintained after 60Co irradiation. Serum produced from Crotalus durissus terrificus irradiated venom showed higher potency and neutralization capacity than that from natural venom. All antibodies were able to neutralize five LD50 from these venoms. Clinical alterations were minimum during hyperimmunization with irradiated venom

Immunological cross-reactivity and neutralization of the principal toxins of Naja sumatrana and related cobra venoms by a Thai polyvalent antivenom (Neuro Polyvalent Snake Antivenom)

“…The underlying mechanism of the latter method is not clearly known; it is presumably associated with structural changes in the peptides induced by gamma-ray radiation which then accelerate antigen processing by macrophages. Therefore, a high level of antibodies can be generated in response to increased epitopes presented by macrophages (Ferreira Junior et al, 2005). It cannot be ascertain a priori, whether having a very high level of toxin-specific antibodies with high avidity will overcome the limitations discussed above, but it is an approach worth considering.…”

Laboratory evaluation of young ovines inoculated with natural or 60co-irradiated Crotalus durissus terrificus venom during hyperimmunization process

“…Gamma radiation has been efficient in attenuating ophidic venoms and in decreasing toxicity without altering immunogenicity, and the addition of substances to the venom was not necessary (1,2,8,10,16,20,21,32).…”

Resposta imune e capacidade de neutralização de anticorpos produzidos em ovinos jovens imunizados com veneno de Crotalus durissus terrificus nativo e irradiado com Cobalto 60

“…These results confirm data obtained by several authors. 8,20,21,22 Venom neutralizing capacity and potency…”