Content of autoantibodies to bradykinin and beta-amyloid(1-42) as a criterion for biochemical differences between Alzheimer's dementias.

We measured serum content of autoantibodies to beta-amyloid protein Abeta(1-42), its neurotoxic fragment Abeta(25-35), vasopressin, bradykinin, thrombin, antithrombin III, alpha(2)-macroglobulin, and angiotensin II in patients with various forms of Alzheimer's dementias, including presenile and senile dementias of the Alzheimer type. The ratio of antibradykinin and anti-Abeta(1-42) autoantibody contents differed by 39% in these patients. Our results can be used for the development of a new biochemical method for differential diagnostics of dementias of the Alzheimer type.