According to a recent study, a blood test could detect a hazardous protein years before Alzheimer’s disease symptoms arise.
Currently, patients are diagnosed with Alzheimer’s only when they exhibit well-known symptoms of the disease, such as memory loss.
However, experts say that at that point, the best treatment options simply slow the progression of symptoms.
However, research suggests that the seeds of the disease are planted many years before the symptoms that allow diagnosis.
These seeds are termed amyloid beta proteins, and they misfold and cluster together to form oligomers.
Toxic oligomers are thought to grow into Alzheimer’s disease over time, however scientists are still attempting to figure out how this happens.
The University of Washington (UW) developed a laboratory technique that can detect the presence of amyloid beta oligomers in blood samples.
The study suggests that their test, known as SOBA, could detect oligomers in the blood of Alzheimer’s patients but not in the majority of members of a healthy trial group who showed no signs of cognitive impairment at the time the blood samples were taken.
The test, however, was able to detect oligomers in the blood of 11 people who did not have Alzheimer’s disease, according to the study.
When researchers examined the follow-up records for ten of these people, they discovered that all of them had mild cognitive impairment or brain pathology consistent with Alzheimer’s disease years later.
According to the scientists, SOBA detected the toxic oligomers in these ten people before symptoms appeared.
Alzheimer’s, and many other neurodegenerative diseases are marked by damaging clusters of proteins in the brain. Scientists have expended enormous effort searching for ways to treat such conditions but have had limited success…until now. https://t.co/31pNAAMzas
— Washington University in St. Louis (@WUSTL) November 23, 2022
“We believe that SOBA could aid in identifying individuals at risk or incubating the disease, as well as serve as a readout of therapeutic efficacy to aid in the development of early treatments for Alzheimer’s disease,” said senior author Valerie Daggett, a UW professor of bioengineering and faculty member in the UW Molecular Engineering & Sciences Institute.
She added: “What clinicians and researchers have wanted is a reliable diagnostic test for Alzheimer’s disease – and not just an assay that confirms a diagnosis of Alzheimer’s, but one that can also detect signs of the disease before cognitive impairment happens.
“That’s important for individuals’ health and for all the research into how toxic oligomers of amyloid beta go on and cause the damage that they do.
“What we show here is that SOBA may be the basis of such a test.”
According to the researchers, SOBA, which stands for soluble oligomer binding assay, takes advantage of a special characteristic of hazardous oligomers.
When misfolded amyloid beta proteins aggregate into oligomers, they form a structure known as an alpha sheet, which, according to study, likes to cling to other alpha sheets.
The SOBA test incorporates a synthetic alpha sheet that can bind to those found in blood samples.
The test subsequently confirms that the oligomers adhered to the test surface are made of amyloid beta proteins using established procedures.
SOBA was tested on blood samples from 310 research subjects who had previously provided blood samples and some of their medical records for Alzheimer’s research.
They detected oligomers in the blood of people with mild cognitive impairment and moderate to severe Alzheimer’s.
The findings are published in the Proceedings of the National Academy of Sciences.