ANALYSIS AND QUANTITATION OF THE BETA-AMYLOID PRECURSOR PROTEIN IN THE CEREBROSPINAL-FLUID OF ALZHEIMERS-DISEASE PATIENTS WITH A MONOCLONAL ANTIBODY-BASED IMMUNOASSAY

One of the major clinical findings in Alzheimer's disease (AD) is the formation of deposits of beta-amyloid protein in amyloid plaques, derived from the beta-amyloid precursor protein (beta-APP). To determine the possible use of beta-APP as a diagnositc marker for AD in CSF, monoclonal antibody-based immunoassay specific for this protein was developed. The assay does not differentiate between beta-APP695 and beta-APP751 forms but does preferentially recognize beta-APP751 complexed with a protease. Of the two sets of CSF samples tested, one set, obtained from living patients, gave a slightly lower level of beta-APP in AD and Parkinson's disease patients relative to controls, whereas the other set, composed of post-mortem samples, showed no significant differences between the AD and control groups.