Purification of the anti-IgE monoclonal antibody E1 from ascitic fluid

Abstract

Contemporary biochemical methods for protein purification were applied for the isolation of anti-IgE monoclonal antibody E1 from mouse ascitic fluid. The yield of monoclonal antibody E1 in each of the isolated fractions was estimated by determining the total protein concentration and the specific concentration of IgG1. The homogeneity and purity of the isolated protein was determined by SDS PAG electrophoresis. Precipitation methods (ammonium sulphate, polyethylene glycol, caprylic acid, rivanol) were used, alternatively or successively, as the first step in the isolation of MoAb E1. Higher levels of purity of monoclonal antibody E1 were obtained using chromatographic methods (ion exchange chromatography, gel filtration and affinity chromatography). The best result (97% purity and 77% yield) was obtained by affinity chromatography on Staphylococcal protein A.