Detection of apolipoprotein E dimeric soluble amyloid beta complexes in Alzheimer's disease brain supernatants

The inheritance of the apolipoprotein (ape) E4 allele is an important risk factor for late-onset Alzheimer's disease (AD). A major component of the Alzheimer's disease neuritic plaques is amyloid beta (A beta). We previously identified apoE/A beta complexes within neuritic plaques (I). It was not known if this interaction takes place before or after A beta peptides become incorporated into neuritic plaques. To address this question we sought evidence of apoE complexes with brain soluble A beta peptides in AD and control patients. In addition, numerous proteins have been shown to bind A beta peptides in vitro. It is not know if any of these bind brain sA beta in vivo. me found evidence for the presence of apoE/dimeric sA beta complexes in the AD brain and could not detect complexes with other A beta peptide binding proteins. The binding of sA beta to apoE may be one factor influencing its clearance from the brain and/or its conformational state. (C) 1997 Academic Press.