Scientists develop new biosensor to test for Alzheimer’s disease
Study by University of Leeds researchers could form the basis of a simple blood test to diagnose Alzheimer’s disease.
A team from the University of Leeds (Leeds, UK) has recently developed a new technology that could lay the foundations for a simple blood test to easily diagnose Alzheimer’s disease (AD). AD is the most common form of dementia, claiming the lives of one in three people over the age of 65 in the UK; however, there is currently no way to conclusively diagnose this disease until after death.
Jo Rushworth, Research Fellow at the University’s School of Biological Sciences, who led the study, commented, “At present, if you go to a doctor, they will do a memory test and then may say you have dementia. They may also say that AD is the probable cause, but the only way to definitively find out whether someone had the disease is to examine the brain after death. Because we are relying on symptoms, drugs are given to the patient late. What we need is a reliable early test so we can intervene when it is actually going to be of some use. If we were able to diagnose AD earlier, the symptoms could be better managed and future treatments could be given at a time when they would have most effect.”
Characterized by deposits of the protein amyloid-beta, the new biosensor measures clusters of this protein as an early indicator of AD. Blood levels of this protein have been demonstrated to correlate with the level of amyloid-beta deposits in the brain, which is linked to AD onset and severity. The biosensor, which is contained on a small gold chip, generates an electric signal in the presence of amyloid clusters with the signal strength indicating the number of clusters in the sample.
“In AD, you get lots of big sticky balls of amyloid-beta, made up of many individual amyloids, which latch onto brain neurons,” explained Rushworth. “This key event triggers disruption of neuronal communication and leads to the eventual death of the neurons. Until now, it has been very difficult to pick out these clusters from the individual amyloid proteins that are present in healthy people. Our biosensor test uses a new molecular recognition toll that works like a lock that only fits one key; it picks out the ball-shaped amyloid clusters without detecting the individual amyloids.”
Testing the biosensor on amyloid clusters generated by cells in vitro, the sensor was able to pick out clusters similar to those found in AD patients. Rushworth concluded, “We are still at the laboratory stage but, eventually, if we are able to develop this technology, we would be looking to have a mobile phone-sized device where you could do a finger-prick blood test and get an immediate readout telling the doctor the level of these markers in your system.”
Source: New research opens door to Alzheimer’s test.
