The antigenic determinant of fibrin(ogen) measured with agglutination inhibition immunoassays

Agglutination inhibition immunoassays using antifibrinogen antiserum measure an antigenic determinant of fibrinogen which is located on the fragment D parts of this molecule. This antigenic determinant of fragment D, in contrast to others, does not form an immune precipitate with antifibrinogen antiserum. Upon very extensive hydrolysis by plasmin, this antigenic determinant has a reduced affinity for its antibody.