Researchers have made significant strides in the field of Alzheimer’s diagnostics with the development of a groundbreaking blood test aimed at patients experiencing thinking and memory issues. This innovative test not only checks for the presence of Alzheimer’s disease but also assesses the extent of its progression. The team behind this research believes that this test could play a crucial role in guiding healthcare professionals in determining which medications are most suitable for their patients, particularly as new drugs like donanemab and lecanemab show promise in slowing disease progression.
Prof. Oskar Hansson from Lund University, a co-author of the study, emphasized the pressing need for accurate and cost-effective Alzheimer diagnostics, especially since many countries have recently approved the clinical use of amyloid-targeted therapies such as donanemab and lecanemab. The presence of plaques composed of a protein known as amyloid beta, alongside the formation of tangles made up of another protein called tau, are considered defining characteristics of Alzheimer’s disease.
In a publication in the journal Nature Medicine, Hansson and his colleagues revealed that they were able to detect fragments of tau, specifically known as eMTBR-tau243, in the blood of individuals. This discovery correlated with the accumulation of tau tangles in the brains of Alzheimer’s patients, while remaining absent in individuals suffering from other diseases. The research involved a comprehensive analysis of 902 participants and indicated that levels of this tau fragment were notably elevated in individuals exhibiting Alzheimer’s symptoms, particularly those with mild cognitive impairment, and were even higher in those diagnosed with dementia.
Importantly, raised levels of eMTBR-tau243 were not found in individuals experiencing cognitive impairments due to alternative conditions. Prof. Tara Spires-Jones, a neurodegeneration expert at the University of Edinburgh who was not involved in the study, remarked on the promising nature of these results, highlighting that this new marker outperformed existing tests and could facilitate monitoring the efficacy of new drugs in clinical trials. However, she cautioned that this is not a foolproof blood test for Alzheimer’s disease.
Dr. Sheona Scales, head of research at Alzheimer’s Research UK, noted that eMTBR-tau243 is one of several biomarkers being investigated for potential use in blood tests targeting Alzheimer’s disease. She pointed out the interesting connection between blood levels of eMTBR-tau243 and an individual's memory and cognitive abilities. Currently, making a direct link between imaging results and cognitive impairment levels can be challenging. However, the introduction of blood tests that correlate with these measures will enhance the ability to monitor Alzheimer’s progression and improve prognostic capabilities in the future.
Complementing these findings, another study published in Nature Medicine revealed insightful data regarding the ratio of two proteins in brain fluid, which is associated with the degree of cognitive impairment in Alzheimer’s patients. This research was spearheaded by scientists in the United States and involved samples from 3,397 individuals across the US, Sweden, and Finland. The focus was on two proteins, YWHAG and NPTX2, typically found at the synapses between neurons.
The study demonstrated that the ratio of YWHAG to NPTX2 proved to be a more accurate indicator of cognitive issues than the levels of amyloid beta and tau. This finding suggests that this protein ratio could serve as a valuable tool for predicting future cognitive decline and the onset of dementia. Prof. Tony Wyss-Coray from Stanford University, a co-author of this research, stated that these results could be instrumental in identifying the most effective medications for individuals and in designing better clinical trials by selecting appropriate participants.
