Production and immunochemical study of monoclonal antibodies directed against human low density lipoprotein.

The purpose of this work is to produce monoclonal antibodies directed against Human Low Density Lipoprotein (LDL). Because of the importance of an early characterization in isotypes of the monoclonal antibodies we carefully analyzed three different techniques: double gel diffusion, competition ELISA and immunodot isotyping technique. The three methods gave essentially the same results but greatly differed in sensitivity. We are purifying all the IgG monoclonal antibodies by affinity chromatography from mouse ascitic fluid using Protein A-Sepharose. Here we report details of the purification of one of these monoclonal antibodies. Fractions eluted at different pH values displayed multiple bands by isoelectric focusing, which could be stained for proteins and recognized by radiolabelled Protein A with the electroblotting technique.