Characterization of stable complexes involving apolipoprotein E and the amyloid β peptide in Alzheimer's disease brain

Ludwig Institute for Cancer Research Biomedical Center S-751 24 Uppsala, Sweden
Neuron (Impact Factor: 15.98). 08/1995; 15(1):219-228. DOI: 10.1016/0896-6273(95)90079-9

ABSTRACT Genetic evidence suggests a role for apolipoprotein E (apoE) in Alzheimer's disease (AD) amyloidogenesis. Here, amyloid-associated apoE from 32 AD patients was purified and characterized. We found that brain amyloid-associated apoE apparently exists not as free molecules but as complexes with polymers of the amyloid β peptide (Aβ). Brain Aβ-apoE complexes were detected irrespective of the apoE genotype, and similar complexes could be mimicked in vitro. The fine structure of purified Aβ-apoE complexes was fibrillar, and immunogold labeling revealed apoE immunoreactivity along the fibrils. Thus, we conclude that Aβ-apoE complexes are principal components of AD-associated brain amyloid and that the data presented here support a role for apoE in the pathogenesis of AD.

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