>Scientists have developed a blood test to diagnose Alzheimer’s disease without the need for expensive brain imaging or a painful lumbar puncture, where a sample of cerebrospinal fluid (CSF) is drawn from the lower back.
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>Although current blood tests can accurately detect abnormalities in amyloid and tau proteins, detecting markers of nerve cell damage that are specific to the brain has been harder. Karikari and his colleagues around the world focused on developing an antibody-based blood test that would detect a particular form of tau protein called brain-derived tau, which is specific to Alzheimer’s disease.
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>If validated, the test could enable faster diagnosis of the disease, meaning therapies could be initiated earlier.

Article: Brain-derived tau: a novel blood-based biomarker for Alzheimer’s disease-type neurodegeneration https://doi.org/10.1093/brain/awac407