Every 3.2 seconds, someone is diagnosed with Alzheimer’s disease, a form of dementia that causes cognitive problems and memory loss 1. While there is currently no cure for this condition, early diagnosis may provide more treatment options. It is estimated that 28 million of the 36 million people with dementia worldwide have not yet been diagnosed 2.
Researchers from the University of Washington have created a lab test that can detect levels of amyloid beta oligomers in the blood as a means of earlier detection of Alzheimer’s disease. The test was able to identify oligomers in the blood of individuals with mild cognitive impairment (MCI) or moderate to severe Alzheimer’s, and also detected oligomers in the blood of people in the control group who later developed MCI 3,4.
What are amyloid beta oligomers?
Amyloid beta oligomers are small protein clusters that form in the brain due to the aggregation of amyloid beta peptides. These peptides are produced when an amyloid precursor protein is broken down. In some people, amyloid beta oligomers can build up in the brain and contribute to the development of Alzheimer’s disease. They are thought to play a role in the death of brain cells and the development of plaques in the brain, which are characteristic of Alzheimer’s disease. Amyloid beta oligomers are one of the targets of research into potential treatments for Alzheimer’s disease 3.
SOBA laboratory test for Alzheimer’s
Researchers have created a laboratory test called SOBA (soluble oligomer binding assay) to detect amyloid beta protein oligomers in blood samples. According to Dr. Valerie Daggett, a professor at the University of Washington and senior author of the study, brain damage related to Alzheimer’s disease may occur for 10-20 years before symptoms appear 3,4.
Dr. Daggett and her team used the SOBA test on blood samples from 310 people with various stages of cognitive impairment, including no impairment, mild cognitive impairment (MCI), Alzheimer’s disease, and other forms of dementia. The SOBA test detected oligomers in the blood samples of people with MCI and moderate to severe Alzheimer’s disease. In 53 cases where an autopsy confirmed an Alzheimer’s diagnosis, toxic oligomers were found in the blood in 52 of those cases 3,4.
Early detection of Alzheimer’s disease
The SOBA test also detected oligomers in the blood of 11 people in the study’s control group. Upon reviewing their follow-up examination records, researchers found that 10 of these individuals later received diagnoses of MCI or brain pathology consistent with Alzheimer’s disease. Dr. Daggett stated that, based on current scientific understanding, it is expected that amyloid beta toxic oligomers may be one of the earliest triggers of Alzheimer’s disease, occurring before the formation of fibrils and plaques and tau hyperphosphorylation 3.4.
Alzheimer’s test in early research phase
How quickly can the SOBA laboratory test be available for doctors and patients?
Dr. Daggett reported that the SOBA-AD version of the assay has received Breakthrough Device Status from the FDA and that AltPrep is working on commercializing it. However, there is currently no firm timeline for this. In addition to the SOBA-AD test, AltPep is also developing a therapeutic for Alzheimer’s disease that is designed to bind, neutralize, and clear toxic oligomers. They also plan to pursue Breakthrough Status for a test for Parkinson’s disease and Lewy body dementia in plasma 3.
References
- Alzheimer’s Disease International. Dementia facts & figures. Retrieved from: https://www.alzint.org/about/dementia-facts-figures/dementia-statistics/
- Alzheimer’s Disease International. (2011). World Alzheimer report 2011: The benefits of early diagnosis and intervention. Retrieved from https://www.alzint.org/u/WorldAlzheimerReport2011ExecutiveSummary.pdf
- Alzheimer’s blood test may detect toxic protein years before symptoms emerge. Medical News Today. Retrieved from https://www.medicalnewstoday.com/articles/alzheimers-blood-test-may-detect-toxic-protein-years-before-symptoms-emerge
- Johnson, K. A., Strittmatter, S. M., & Daggett, V. (2022). Early detection of Alzheimer’s disease in blood. Proceedings of the National Academy of Sciences, 119(52), 2213157119. Retrieved from https://www.pnas.org/doi/10.1073/pnas.2213157119
