Neutralization of lethal potency and inhibition of enzymatic activity of a phospholipase A2 neurotoxin, crotxin, by non‐precipitating antibodies (Fab)

FEBS Letters

Ownby, Charlotte¹  Choumet, Valérie¹  Jiang, Ming-Shi¹  Radvanyi, François¹  Bon, Cassian¹ 

[1] Laboratoire des Venins, Unité associée Pasteur/INSERM 285, Institut Pasteur, 25 rue du Dr Roux, 75724 Paris, France

关键词: Phospholipase A2;    Snake venom neurotoxin;    Lethal potency neutralization;    Enzymatic inhibition;    Neutralizing antibody;    Neutralizing Fab;   

DOI  :  10.1016/0014-5793(89)81185-8

学科分类：生物化学/生物物理

来源: John Wiley & Sons Ltd.

【 摘 要 】

Rabbit antibodies were prepared against both purified catalytic (component-B) and purified non-catalytic (component-A) subunits of crotoxin, the major phospholipase A₂ neurotoxin from the South American rattlesnake. They cross-react with crotoxin-like toxins from the venom of several Crotalus species as well as with single-chain phospholipase A₂ neurotoxins from Crotalid and Viperid venoms (agkistrodontoxin and ammodytoxin A) but not from Elapid venoms (notexin). Immunological cross-reactions of anti-component-A and anti-component-B sera with crotoxin and with its isolated components A and B showed that component-A exposes determinants of low immunogenicity which are present on component-B, whereas the major antigenic determinants of component-B are not present on component-A. Anti-component-B anti-bodies, but not anti-component-A antibodies, neutralize the lethal potency of crotoxin and inhibit its enzymatic activity. Furthermore, non-precipitating anti-component-B Fab fragments were as potent as antibodies, indicating that crotoxin neutralization results from the binding of the antibodies to the catalytic subunit, rather than the formation of an immuno-precipitate.

【 授权许可】

Unknown