Monoclonal antibodies of predetermined specificity for fibrin: a rational approach to monoclonal antibody production.

Three monoclonal antibodies (MAbs) (55D10, 59D8, and 64C5) have been produced by an immunization strategy that uses a synthetic heptapeptide from the amino terminus of the beta-chain in human fibrin. These MAbs bind to human fibrin in the presence of 4 mg/ml human fibrinogen in solid-phase radioimmunoassay. Ligand specificity studies demonstrate that antifibrin immunoreactivity is completely inhibited by a series of synthetic fibrin-like beta-peptides that bear the position-2 histidyl residue. Although the presence of this residue on the epitope is necessary for its recognition by a fibrin-specific antibody, the presence of the histidyl residue alone is not sufficient for antibody recognition.