Alzheimer’s blood test developed
Australian and Japanese collaboration concludes three-decade hunt for effective diagnostic method. Andrew Masterson reports.
A combined Australian-Japanese research project has produced a potentially revolutionary blood test for the detection of Alzheimer’s disease – raising hopes of earlier and more precise interventions in the treatment of the devastating condition.
In a paper in the journal Nature, scientists from bodies including the Florey Institute in Melbourne, Australia, and the Shimadzu Corporation in Kyoto, Japan, outline a blood test that uses mass spectrometry to detect the presence of the key biomarker for Alzheimer’s – a protein called amyloid-beta – with an accuracy of greater than 90%.
The test has so far been trialled on two cohorts – comprising 252 Australian and 121 Japanese volunteers – and has successfully detected low levels of amyloid-beta fragments in the blood.
Although at an early stage, the success of the trial raises the possibility that Alzheimer’s could be detected much earlier than is currently possible – well before symptoms become apparent. It may also allow earlier and better distinctions between different types of dementia, and permit ongoing monitoring of the effectiveness of treatments.
Current diagnostics for the disease rely either on positron-emission tomography – known as PET scans – to detect amyloid-beta deposits in the brain or lumbar punctures to measure amyloid-beta concentrations in the cerebrospinal fluid.
At a press conference to announce the discovery, Colin Masters from the Florey Institute said the new approach “is as good as, if not better than, the existing tests.”
For Masters and his colleagues at Florey, the success of the current work marks an important step in a very long research journey. “We’ve been working on a blood test since 1989,” he said.
Mass spectrometry is an analytical method that is widely used in medicine and industry. It involves ionising chemicals in a sample and then classifying them according to their mass-to-charge ration, enabling precise identification.
Calibrating the specific approach for the Alzheimer’s blood test was the responsibility of the Shimadzu Corporation’s Koichi Tanaka, who was awarded the Nobel Prize for Chemistry in 2002 for his work on using the technique to analyse biological macro molecules.
The blood tests carried out on the Japanese and Australian volunteers were all conducted in Tanaka’s laboratory, and Masters says the next step in the development process is to roll the test out to other researchers.
“We need to scale it up next,” he said. “The Shimadzu Corporation say they can do that within the next six to 12 months, but that remains to be seen.”
For Masters, however, even getting to this stage brings considerable personal satisfaction.
“We can finally say that we have a high-performing blood test,” he said, “which from my point of view is a major achievement.”