Antibodies to the β-amyloid peptide cross-react with conformational epitopes in human fibrinogen subunits from peripheral blood

Abstract

Antibodies to the Alzheimer disease (AD) β-amyloid peptide (βAP) were used to identify βAP precursor fragments in blood. The antibodies detected 3 major polypeptides with apparent molecular weights (MW) of 47-64000 in Western blots of plasma derived clot proteins, but these proteins corresponded to human A-α, B-β and γ-fibrinogen since they reacted with 2 different anti-fibrinogen antisera, and the anti-βAP and anti-fibrinogen antibodies recognized purified fibrinogen and fibrin. These data are significant for efforts to develop immunochemical assays to diagnose and monitor the progression of AD.