Monoclonal antibodies to human protamines.

Nine monoclonal antibodies to human protamine, hup1a, 1b, 1c, 1d, 1e, 2a, 2b, A, and B, have been isolated and partially characterized. Enzyme-linked immunoabsorption assay analyses with HPLC-separated human protamine 1 and protamine 2+3 mixture identified five of these antibodies as specific for human protamine 1, two antibodies specific for protamine 2+3 mixture and two monoclonal antibodies reactive with all three human protamines. These findings were confirmed by immunoblotting. None of the antibodies reacted with poly-arginine or somatic histone proteins. Additional analyses with bull, boar, and ram protamines indicated that all of the monoclonal antibodies except hupA are specific for human protamine. HupA reacted with protamines from all of the species tested. These studies suggest that each of the antibodies recognizes one of at least four distinct epitopes on protamine.