New immunization protocol to produce crotalic antivenom combining Crotalus durissus terrificus venom and its PLA2

LUCIANO SEBASTIAN FUSCO; JUAN PABLO RODRÍGUEZ; PAMELA TEIBLER; SILVANA MARUNAK; OFELIA ACOSTA; LAURA LEIVA

BIOLOGICALS

ACADEMIC PRESS LTD-ELSEVIER SCIENCE LTD

Lugar: Amsterdam; Año: 2015 vol. 43 p. 62 - 70

1045-1056

Antivenoms are usually obtained by animal immunization with successive inoculations of increasing sublethal amounts of venom, which may impair the animal health. The high lethality of venom requires prolonged immunization plans with small amounts of venom. Thus, we propose an alternative plan that includes a pre-immunization of the animal with phospholipase A2, the main crotoxin component, which is responsible for the whole venom lethality. For comparison, three different immunization schemes were designed: high dose protocol (HDP; 0.5e27 mg of venom), low dose protocol (LDP; 0.1e7 mg of venom) and Mix protocol (MP; preimmunization 0.1e1.2 mg of crotalic PLA2, and then 4.5e8 mg of venom). Antibody titers were determined by ELISA, in blood plasma obtained from the marginal vein of the ear. The neutralizing ability of the different sera obtained by all protocols (HDS, LDS and MS) was tested against the most important pharmacological activities of whole venom: PLA2 activity, myotoxicity, thrombin like activity and lethality. MS showed the best neutralizing efficacy and at the same time, it was obtained by an immunization protocol that takes account of animal health care, since it requires low quantities of venoms in comparison to traditional protocols.