Comparison of four different purification methods for isolation of anti Echis carinatus antivenom antibodies from immunized chicken egg yolk

ABSTRACT

Egg-laying hens were immunized with the Echis carinatus venom and the resulting antibodies were extracted from egg yolk by four different purification methods. The chicken egg yolk antibodies were purified by the water dilution method, polyethylene glycol [PEG] and ammonium sulphate precipitation method, chloroform extraction and the Lithium sulphate precipitation method. These methods were compared in terms of total protein content, immunospecific anti E. carinatus immunoglobulin Y [IgY] activity and in vitro and in vivo neutralizing capacity of IgY against the E. carinatus venom. Total IgY concentrations varied from 1.6 to 7.0 mg per ml of egg yolk. In neutralization studies, IgY purified by PEG and ammonium sulphate precipitation [PEG-AS] showed better results when compared to other purification methods. Approximately 1.25 mg of IgY [PEG-AS] was able to neutralize 2Lethal Dose50 of the E. carinatus venom. Purification of IgY by PEG and ammonium sulphate yielded very pure IgY at high quantities [93% +/- 5% of total egg yolk protein], which was also capable of neutralizing toxic and lethal components of the E. carinatus venom