Activated protein C-protein C inhibitor complex formation: characterization of a neoepitope provides evidence for extensive insertion of the reactive center loop

A conformation-dependent neoepitope in activated protein C-protein C inhibitor complex and the cleaved, loop-inserted protein C inhibitor complex is recognized by a mouse monoclonal antibody. Data indicate that part of the epitope represents the inserted reactive center loop and involves residues ArgP13-AlaP9.