Abstract: Coagulation protein antagonists are disclosed, which include monoclonal-type antibodies and related cell lines disclosed for the production of specific, neutralizing antibodies against factors VII and VIIa and the tissue factor/factor VIIa bimolecular complex, which antibodies are useful for the prevention or treatment of thrombotic and related diseases, for immunoaffinity isolation and purification of factors VII and VIIa and the tissue factor/factor VIIa complex, and for determination of factors VII or VIIa and the tissue factor/factors VII or VIIa complex in a biological sample.