Monoclonal antibodies against plasma protease inhibitors: II. Production and characterization of 25 monoclonal antibodies against human alpha 1-antitrypsin. Correlation between antigenic structure and functional sites.

Twenty-five hybridomas secreting monoclonal antibodies against human alpha 1-antitrypsin have been produced by the cell-fusion technique (Köhler and Milstein, 1976). All antibodies are specific for alpha 1-antitrypsin and carry gamma 1 heavy chains and kappa light chains. Inhibition experiments showed that these monoclonal antibodies define three independent antigenic regions on the alpha 1-antitrypsin molecule; one of these domains appears to be involved in the interaction between alpha 1-antitrypsin and trypsin. In addition, one monoclonal antibody, AATY39, was used to develop an enzyme-linked immunosorbent assay capable of detecting low levels of alpha 1-antitrypsin in the range of 1 to 2 ng/ml.