Diagnosis of Alzheimer's disease through measurement of anti-beta amyloid antibody in patient's serum

Amyloid beta (A$\beta$) is believed one of the major pathogens of Alzheimer's disease (AD), and the reduction of A$\beta$ is considered a primary therapeutic target. Immunization with A$\beta$ can reduce A$\beta$ burden and pathological features in transgenic AD model mouse. This means anti-A$\beta$ autoantibodies may have a role in AD pathology. Recent findings suggest anti-A$\beta$ autoantibodies level decrease in AD patients. The early detection of AD is important for treatment of this disease. However, diagnosis on AD has only been possible through limited methods such as neuropsychological examination or MRI. To investigate whether it was possible to detect the presence and different levels of naturally occurring anti-A$\beta$ autoantibodies in the plasma of patients with AD and age-matched controls. An advanced ELISA was performed to detect levels of naturally occurring anti-A$\beta$ autoantibodies in the plasma. The level of anti-A$\beta$ auto-antibodies from patients with idiopathic Parkinson's disease or stroke and from normal controls were compared to that of AD patients. Our results showed a significantly lower anti-A$\beta$ autoantibodies level in AD compared to those with other neurological diseases or control. The level of anti-A$\beta$ autoantibodies in the serum may be used to diagnose the presence of AD.