A rapid latex agglutination assay for the determination of plasma fibrinogen

A monoclonal antibody to intact fibrinogen has been employed to develop a rapid latex agglutination assay for the estimation of plasma fibrinogen. The monoclonal antibody, 45J, recognizes an epitope located in the mid-section of the carboxy terminal end of the A alpha-chain. The epitope is destroyed by plasmin digestion of fibrinogen and there is no immunoreactivity with soluble cross-linked fibrin degradation products. The latex agglutination assay developed with the antibody is unaffected by aprotinin or anticoagulants, such as citrate, heparin or EDTA. When this method was compared with functional clotting assays, excellent correlation was observed with normal and pathological samples. After sample collection and dilution, the assay takes just two minutes to complete. Therefore, this procedure offers a simple and rapid assay for the measurement of intact fibrinogen in plasma.