A sensitive and specific immunoassay for the measurement of the antibodies present in horse antivenoms endowed with the capacity to block the phospholipase A2-dependent hemolysis induced by snake venoms



Document title: A sensitive and specific immunoassay for the measurement of the antibodies present in horse antivenoms endowed with the capacity to block the phospholipase A2-dependent hemolysis induced by snake venoms
Journal: The journal of venomous animals and toxins
Database: PERIÓDICA
System number: 000298550
ISSN: 0104-7930
Authors: 1



Institutions: 1Instituto Butantan, Laboratorio de Imunoquimica, Sao Paulo. Brasil
Year:
Volumen: 2
Number: 2
Pages: 106-120
Country: Brasil
Language: Inglés
Document type: Artículo
Approach: Experimental, aplicado
English abstract Phospholipase A2 (PLA2), a component of most snake venom toxins, cleaves 3-sn-phosphoglycerides releasing lysophosphatidyl-choline. The indirect quantitative assay method for PLA2 was standardized for specific antivenom titration in a fast and sensitive assay by the similarity with the hemolysis induced by PLA2 and by complement system in sheep erythrocytes. The curves obtained by plotting the degree of hemolysis against the doses of snake venom are concave to the abscissa axis following an equation similar to that previously described for the hemolysis induced by the C system. We observed that venoms of some Bothrops, Crotalus and Micrurus species contained around 1 x 10 to 10 Z/mg of venom, while the venom of Naja contained over one million Z/mg. Antibodies against PLA2 were titrated by incubating amounts of venom predetermined to give 1 to 5 Z with various dilutions of the antivenoms, and the remaining active PLA2 was determined in the hemolytic assay. We observed the following: a) the antivenoms contained specific antibodies against the PLA2 present in the corresponding venoms; b) cross-reactivity was not detected among PLA2 epitopes from venoms and nonspecific antivenoms; and c) the assay quantitatively performed determined the specific antibodies directed to epitopes on the molecule of PLA2. The method described in this paper is highly specific, sensitive and reproducible, besides being fast and inexpensive
Disciplines: Medicina
Keyword: Toxicología,
Inmunología,
Veneno de víbora,
Antivenenos,
Inmunoensayo,
Hemólisis indirecta,
Fosfolipasa A2,
Inhibición enzimática
Keyword: Medicine,
Toxicology,
Immunology,
Snake venom,
Antivenoms,
Immunoassay,
Indirect hemolysis,
Phospholipase A2,
Enzymatic inhibition
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