A sensor detects misfolded protein biomarkers in the blood. This allows for the detection of Alzheimer’s disease before any symptoms occur. The researchers seek to get it ready for the market.
The findings from the immuno-infrared sensor were published in the journal Alzheimer’s & Dementia: The Journal of the Alzheimer’s Association. A comparison study published in the same journal on 2 March 2022, in which the researchers employed complementary single-molecule array (SIMOA) technology, lends credence to this finding.
Alzheimer’s disease has a 15 to 20-year symptom-free interval before the first clinical signs appear. A study team using an immuno-infrared sensor created in Bochum is able to detect indicators of Alzheimer’s disease in the blood up to 17 years before the first clinical symptoms arise. The sensor detects the protein biomarker amyloid-beta misfolding. As the disease advances, this misfolding results in distinctive deposits in the brain, known as 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 can form in the brain, in order to ensure that a therapy can be initiated in time,” says Professor Klaus Gerwert, founding director of the Centre for Protein Diagnostics (PRODI) at Ruhr-Universitat Bochum. His team cooperated for the study with a group at the German Cancer Research Centre in Heidelberg (DKFZ) headed by Professor Hermann Brenner.
The team published the results obtained with the immuno-infrared sensor in the journal Alzheimer’s & Dementia: The Journal of the Alzheimer’s Association on 19 July 2022. This study is supported by a comparative study published in the same journal on 2 March 2022, in which the researchers used complementary single-molecule array (SIMOA) technology.
Early detection of symptom-free people with a high risk of Alzheimer’s disease
The researchers looked for possible Alzheimer’s biomarkers in blood plasma from participants in the ESTHER trial in Saarland. The blood samples were collected and frozen between 2000 and 2002. The test participants were between the ages of 50 and 75 at the time and had not yet been diagnosed with Alzheimer’s disease. The current study compared 68 people who had been diagnosed with Alzheimer’s disease over the 17-year follow-up to 240 control subjects who had not been diagnosed. The researchers, led by Klaus Gerwert and Hermann Brenner, wanted to see if there were any indicators of Alzheimer’s disease 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 test accuracy. For comparison, the researchers examined other biomarkers with the complementary, highly sensitive SIMOA technology — specifically the P-tau181 biomarker, which is currently being proposed as a promising biomarker candidate in various studies. “Unlike in the clinical phase, however, this marker is not suitable for the early symptom-free phase of Alzheimer’s disease,” as Klaus Gerwert summarises the results of the comparative study.
“Surprisingly, we found that the concentration of glial fibre protein (GFAP) can indicate the disease up to 17 years before the clinical phase, even though it does so much less precisely than the immuno-infrared sensor.” Still, by combining amyloid-beta misfolding and GFAP concentration, the researchers were able to further increase the accuracy of the test in the symptom-free stage.
The Bochum researchers hope that an early diagnosis based on the amyloid-beta misfolding could help to apply Alzheimer’s drugs at such an early stage that they have a significantly better effect — for example, the drug Aduhelm, which was recently approved in the USA. “We plan to use the misfolding test to establish a screening method for older people and determine their risk of developing Alzheimer’s dementia,” says Klaus Gerwert. “The vision of our newly founded start-up betaSENSE is that the disease can be stopped in a symptom-free stage before irreversible damage occurs.”
Even though the sensor is still in the development phase, the invention has already been patented worldwide. BetaSENSE aims to bring the immuno-infrared sensor to market and have it approved as a diagnostic device so that it can be used in clinical labs.