Comparative Analysis of the Efficiency of Chicken and Rabbit Antibodies in Competitive Enzyme Linked Immunoassay for the Detection of Bovine Beta-Casomorphin 7

Abstract

Rabbit and chicken (IgY) polyclonal antibodies were compared with respect to their performance in competitive enzyme linked immunoassays (ELISA) for the determination of opioid peptide β-casomorphin 7 (BCM-7) released from variant A1 of bovine β-casein. To obtain antibodies, the animals (four rabbits and four hens) were immunized (with similar regimes) with BCM-7 conjugated to bovine serum albumin. Comparison of the binding curves of biotinylated BCM-7 obtained with affinity-purified mammalian and avian antibodies immobilized on the surface of polystyrene microtiter immunoplates via passive adsorption (in optimal conditions) showed that rabbit antibodies captured biotinylated antigen 100 times more efficiently than hen antibodies within the given antibody panel. The most efficient rabbit antibodies were used to construct a highly sensitive, competitive ELISA for the detection of BCM-7 (the minimal detection limit was 0.2 ng/mL). The chicken antibodies proved unsuitable for such use due to their low affinity. These results indicate that it is necessary to make comparisons with methods based on mammalian antibodies in the construction of quantitative ELISA based on chicken polyclonal antibodies.