Plasma biomarkers for Alzheimer’s

Abstract

Protein clumps called amyloids accumulate in the brains of people with Alzheimer’s disease. The current methods for detecting amyloids—positron emission tomography (PET) imaging of the brain and measurement of the clumping protein amyloid-β in cerebrospinal fluid—are expensive and invasive. Researchers want more easily accessible biomarkers that can provide the same information, but they’ve had no luck so far. An international team led by Katsuhiko Yanagisawa of the Japanese National Center for Geriatrics & Gerontology now reports a promising set of amyloid biomarkers from blood plasma (Nature 2018, DOI: 10.1038/nature25456). The researchers pull target peptides out of plasma using immunoprecipitation and analyze them by mass spectrometry. Rather than use individual peptides as biomarkers, the researchers use peptide ratios. They measure levels of three peptides derived from the amyloid precursor protein—one that is involved in amyloid formation and two that are not—and calculate the ratios. The research ...