| Abstract: | Partially purified dog hepatic lipase was used as antigen to produce monoclonal antibodies in mice. In addition to enzyme-linked immunosorbent assay (ELISA), a reliable and efficient procedure for screening antibodies reacting to hepatic lipase has been developed. A method to distinguish antibodies directing to active site or non-active site epitopes has also been described. We obtained three positive clones that survived after subcloning and expansion. All three monoclonal antibodies possess gamma one (gamma 1) heavy chains and kappa (kappa) light chains. Specificity of monoclonal antibody LDHL No. 537 to dog hepatic lipase was demonstrated by passing post-heparin plasma through its immunoaffinity column. Only dog hepatic lipase was removed by LDHL No. 537 from post-heparin plasma. The immunoaffinity chromatography also demonstrated the co-existence of three enzyme activities (mono- and triacylglycerol lipase and phospholipase A1) on the dog hepatic lipase molecule. The subunit weight of dog hepatic lipase has been estimated at 57500 +/- 600 (n=3) by using immunoaffinity chromatography and the combination of immunoprecipitation and autoradiography methods. |
