Evaluation of the protective efficacy of immunoglobulin Y (IgY- antibodies) prepared against <i>Walterinnesia aegyptia</i> snake venom in Saudi Arabia

Abstract

Four groups of eight chickens were immunized intramuscularly with Walterinnesia aegyptia snake venoms mixed with Freund's complete adjuvant during the period from 1st October 2009 to 1st October 2011 at the Center of Excellence in Biotechnology Research, King Saud University, Saudi Arabia. Three weeks later, the injections were repeated with the venoms in incomplete Freund's adjuvant. Three boosters were given with the venoms at three weeks intervals. The immunoglobulin Y (IgY)-antibodies was extracted by ammonium sulphate-caprylic acid method, the antibody titer were tested by enzyme linked immunosorbant assay and the protective efficacies of the extracted immunoglobulins were performed. IgY-preparation extracted by ammonium sulphate-caprylic acid method showed lack of low molecular weight bands (non-immunoglobulin proteins) and the bands representing IgY-antibodies, which have molecular weights ranging from 180 to 200 kDa, appeared sharp and clear. Moreover, evaluation of the protective value of the IgY - antibodies prepared revealed that, one milliliter of extracted IgY-antibodies containing 15 mg/ml anti-W. aegyptia venom specific IgY could produce 100% protection against 50 LD₅₀ and 75% protection against 60 LD₅₀. Laying hens could be used as an alternative source of polyclonal antibodies against W. aegyptia snake venoms due to several advantages as compared with mammals traditionally used for such purpose.

Keywords: Snake venom, Walterinnesia aegyptia, immunoglobulins Y, protective efficacy, caprylic acid