You are here

A new form of protein in the cerebrospinal fluid determines the stage of Alzheimer's disease

According to a study by the Washington University School of Medicine in St. Louis, a new form of Alzheimer's protein found in the fluid surrounding the brain and spinal cord indicates the stage of the disease a person is in and tracks tau protein tangles in the brain. 

Editor: Akhmetova Aigerim 

Author: Bolysbek Dana 

Translator: Akhmetova Aigerim  



Alzheimer's disease occurs when a brain protein called amyloid begins to form plaques in the brain. During this amyloid stage, which can last for two decades or more, people do not show signs of cognitive decline. However, shortly after the tau protein tangles begin to spread into neurons, people begin to lose memory, and brain scans show increasing atrophy of brain tissue. 


The microtubule binding tau region (MTBR-tau) is an insoluble fragment of the tau protein and a major component of tau tangles. Bateman and his colleagues are developing diagnostic blood tests for Alzheimer's based on amyloid or tau protein, but none of the tests can measure the number of tau tangles at different stages of the disease. 


The researchers found that levels of a certain form - MTBR tau 243 - in cerebrospinal fluid were increased in people with Alzheimer's, and that it increased as cognitive impairment and dementia developed. 


The gold standard for measuring tau protein in the brain is the tau PET scan. To see how their method is up to the gold standard, the researchers compared the amount of tau protein seen on brain scans of 35 people (20 with Alzheimer's and 15 without) to levels of MTBR-243 tau in cerebrospinal fluid. The levels of MTBR-tau 243 were highly correlated with the amount of tau protein identified in the brain scans, suggesting that their method accurately measured how much tau was accumulated in the brain. 


This discovery opens up new possibilities for other therapies for Alzheimer's disease, based on direct targeting of MTBR-tau.