Blood markers for Alzheimer's disease

A series of proteins in blood could form the basis of a test for Alzheimer's disease in the future, say scientists in the US. They employed proteomics to identify proteins that were expressed at different levels in the blood of patients with Alzheimer's disease or mild cognitiive impairment compared with those of healthy control patients. The results are described in Neurology.

From an initial group of 17 differentially expressed proteins, 4 remained after cross-checking against the findings of the Alzheimer's Disease Neuroimaging Initiative (ADNI). They are apolipoprotein E, B-type natriuretic peptide, C-reactive protein and pancreatic polypeptide. Their levels also correlated with the cerebrospinal fluid contents of beta-amyloid proteins, which have been associated with the onset of Alzheimer's disease. It is still too early to say for sure that a blood test based on these proteins would work. One of the next steps should be to confirm the link between the biomarkers in blood and cerebrospinal fluid.