NEUTRALIZING CAPACITY OF ANTISERUM RAISED IN RABBITS AGAINST CROTOXIN FROM Crotalus durissus cascavella VENOM

Beghini, D.G.(1), Panunto, P.C.(2), Hyslop, S.(2), Rodrigues-Simioni, L.(2), Toyama, M.H.(1), Saraguacy-Hernandez, O.S.(2), Novello, J.C.(1), Marangoni, S.(1)

(1)Departamento de Bioquímica, IB, Universidade Estadual de Campinas (UNICAMP), (2)Departamento de Farmacologia, FCM, UNICAMP, Campinas, São Paulo, Brasil.

Objectives:To examine the ability of antiserum against crotoxin(anti-Crtx) and of commercial antiserum in neutralizing the neurotoxic activity of crotoxin from C. d. cascavella venom.

Methods and results: Anti-Crtx serum was produced by immunizing rabbits with crotoxin from C. d. cascavella venom. The presence of anti-Crtx antibodies in the serum was monitored by ELISA. The antibodies produced cross-reacted with crotoxin and its subunits crotapotin and phospholipase A₂. Immunoblotting showed that the anti-Crtx serum recognized crotoxin in C. d. cascavella venom, whereas commercial serum also recognized other venom proteins. The ability of antisera to neutralize the neurotoxicity of crotoxin was assessed in mouse electrically-stimulated phrenic nerve-diaphragm preparations (PND). The time required to produce 50% neuromuscular blockade in PND was 36.6±1 min (n=3) for crotoxin(10 mg/ml) and 64±9 min (n=3) for crotoxin (10 mg/ml) pre incubated with affinity purified anti-CrtxIgG (toxin:antiserum ratio of 1:10), whereas with commercial antiserum there was less than 50% blockade after 120 min.

Conclusion: Rabbit antiserum to crotoxin showed weak neutralization of the neurotoxicity of C. d. cascavella crotoxin compared to commercial antiserum.

Financial support: FAPESP

CORRESPONDENCE TO:

Daniela Gois Beghini, Rua Macedo Soares, 892, Cidade Universitária, Campinas, SP, CEP: 13083-130, Brasil, Email: dgbeghini@hotmail.com