Researchers at the University of Bochum (Germany) have developed an immuno-infrared sensor capable of identifying signs of Alzheimer’s disease in the blood up to 17 years before the first clinical symptoms appear.
As the authors explain in an article published in the scientific journal ‘Alzheimer’s & Dementia: The Journal of the Alzheimer’s Association, this sensor detects the misfolding of the biomarker protein beta-amyloid. As the disease progresses, this misfolding causes characteristic deposits in the brain called plaques.
“Our goal is to determine the risk of developing Alzheimer’s dementia at a later stage with a simple blood test, even before the toxic plaques form in the brain, to ensure that therapy can be started at time”, explains Dr. head of the book. , Professor Klaus Gerwert.
Alzheimer’s disease has an asymptomatic course of 15 to 20 years before the appearance of the first clinical symptoms. The researchers analyzed the blood plasma of the study participants to detect possible biomarkers of Alzheimer’s disease.
The blood samples were taken between 2000 and 2002 and frozen. At the time, the trial participants were between the ages of 50 and 75 and had not yet been diagnosed with Alzheimer’s disease. For the current study, 68 participants who had been diagnosed with Alzheimer’s disease during the 17-year follow-up were selected and compared to 240 control subjects without such a diagnosis. The team investigated whether signs of Alzheimer’s disease could already be found in the blood samples at the start of the study.
The immuno-infrared sensor was able to identify the 68 test subjects who later developed Alzheimer’s disease with a high degree of accuracy in the test. For comparison, the researchers examined other biomarkers with the complementary and highly sensitive technology of SIMOA, in particular the biomarker P-tau181, which is currently proposed as a promising biomarker candidate in various studies.
“However, unlike the clinical phase, this marker is not suitable for the symptomless early phase of Alzheimer’s disease. Surprisingly, we found that the concentration of glial fiber protein (GFAP) can indicate the disease up to 17 years before the clinical phase, although it does so with much less precision than the immuno-infrared sensor”, summarizes another of the authors, Klaus Gerwert.
Yet, by combining beta-amyloid misfolding and GFAP concentration, the researchers were able to further increase the accuracy of the test in the symptom-free phase.