DEVELOPMENT OF A MONOCLONAL-ANTIBODY SPECIFIC FOR THE COOH-TERMINAL OF BETA-AMYLOID-1-42 AND ITS IMMUNOHISTOCHEMICAL REACTIVITY IN ALZHEIMERS-DISEASE AND RELATED DISORDERS

The beta-amyloid peptide (beta AP) has been characterized by protein s equencing techniques as a 39-43 amino acid protein with heterogeneous COOH-terminal. Controversy exists regarding the predominant form of be ta AP in neuritic plaques (NP) and cerebral vasculature of Alzheimer's disease (AD) brain. A monoclonal antibody was developed that selectiv ely recognizes the free COOH-terminal of beta AP 1-42 but not beta AP species with shorter or longer COOH-terminal. Brain sections from AD a nd related disorders were examined using this antibody. In AD samples, the antibody stained diffuse amyloid and NP cores, many intraneuronal and extraneuronal neurofibrillary tangles (NFT), but not cerebrovascu lar amyloid. Pick and Lewy bodies lacked immunoreactivity. These findi ngs suggest that beta AP 1-42 is present in early and mature amyloid d eposits and NFT, but that species of beta AP other than 1-42 comprise human vascular deposits.