A functional and thromboelastometric-based micromethod for assessing crotoxin anticoagulant activity and antiserum relative potency against Crotalus durissus terrificus venom

Autor(es)

Prezoto, B. C. ^[1] ; Tanaka-Azevedo, A. M. ^[2] ; Marcelino, J. R. ^[3] ; Tashima, A. K. ^[4] ; Nishiduka, E. S. ^[4] ; Kapronezai, J. ^[5] ; Mota, J. O. ^[1] ; Rocha, M. M. T. ^[2] ; Serino-Silva, C. ^[2] ; Oguiura, N. ^[5]

Afiliação do(s) autor(es)

^[1] Butantan Inst, Lab Pharmacol, Av Dr Vital Brazil 1500, BR-05503900 Sao Paulo, SP - Brazil

^[2] Butantan Inst, Lab Herpetol, Av Dr Vital Brazil 1500, BR-05503900 Sao Paulo, SP - Brazil

^[3] Butantan Inst, Immunol Serv, Av Dr Vital Brazil 1500, BR-05503900 Sao Paulo, SP - Brazil

^[4] Univ Fed Sao Paulo UNIFESP, Escola Paulista Med, Dept Biochem, Rua Botucatu 862, Ed Jose Leal Prado, 1st Floor, BR-04023901 Sao Paulo, SP - Brazil

^[5] Butantan Inst, Ecol & Evolut Lab, Av Dr Vital Brazil 1500, BR-05503900 Sao Paulo, SP - Brazil

• Tipo de documento: Artigo Científico
• Fonte: Toxicon; v. 148, p. 26-32, JUN 15 2018.
• Citações Web of Science: 0

Resumo

The assessment of the capacity of antivenoms to neutralize the lethal activity of snake venoms still relies on traditional rodent in vivo lethality assay. ED50 and LD50 assays require large quantities of venoms and antivenoms, and besides leading to animal suffering. Therefore, in vitro tests should be introduced for assessing antivenom neutralizing capacity in intermediary steps of antivenom production. This task is facilitated when one key lethal toxin is identified. A good example is crotoxin, a P-neurotoxin phospholipase A(2)-like toxin that presents anticoagulant activity in vitro and is responsible for the lethality of venoms of Crotalus durissus snakes. By using rotational thromboelastometry, we reported recently one sensitive coagulation assay for assessing relative potency of the anti-bothropic serum in neutralizing procoagulant activity of Bothrops jararaca venom upon recalcified factor-XII-deficient chicken plasma samples (CPS). In this study, we stablished conditions for determining relative potency of four batches of the anti-crotalic serum (ACS) (antagonist) in inactivating crotoxin anticoagulant activity in CPS (target) simultaneously treated with one classical activator of coagulation (agonists). The correlation coefficient (r) between values related the ACS potency in inactivating both in vitro crotoxin anticoagulant activity and the in vivo lethality of whole venom (ED50) was 0.94 (p value < 0.05). In conclusion, slowness in spontaneous thrombin/fibrin generation even after recalcification elicit time lapse sufficient for elaboration of one dose-response curve to pro-or anti-coagulant agonists in CPS. We propose this methodology as an alternative and sensitive assay for assessing antivenom neutralizing ability in plasma of immunized horses as well as for in-process quality control. (C) 2018 Elsevier Ltd. All rights reserved. (AU)

• Processo FAPESP: 17/01890-0 - Estudo comparativo da composição do veneno das serpentes Crotalus durissus terrificus nascidas em cativeiro no Laboratório de Herpetologia do Instituto Butantan e do veneno crotálico de referência nacional
• Beneficiário: Anita Mitico Tanaka-Azevedo
• Modalidade de apoio: Auxílio à Pesquisa - Regular