Alzheimer's diagnosis may gain from PET imaging of tau proteins

An international group of researchers from Japan and the U.S. say they've developed a way to use PET imaging to diagnose Alzheimer's in a living person and then track the disease's advance. The key: an imaging agent drawn to the buildup of tau protein in the brain.

Forbes, the BBC and other news outlets picked up on this major advance, which, if supported by future research, could improve how patients are both diagnosed and treated for Alzheimer's. The journal Neuron carries the full study and its findings.

Right now, the only way to definitively diagnose Alzheimer's is through an autopsy. A number of companies are advancing imaging agents that would help, in theory, to diagnose the disease in living patients. Navidea ($NAVB) is underway with a Phase III trial of an imaging agent that can detect beta-amyloid deposits in the brain--the compound can be a telltale sign of Alzheimer's. GE Healthcare also has an investigative imaging agent that tracks beta-amyloid, and it has done well in Phase III. Both trigger vivid images through PET scans.

As Forbes explains, this new study differed because it relied on a fluorescent material drawn to tau protein, thought to be another sign of Alzheimer's or budding dementia. The substance crossed the blood brain barrier and worked in both mice and several human patients. And as the BBC notes, those tags, combined with positron emission tomography, helped build a three-dimensional image of tau buildup in the brain that clinicians haven't had before.

These are early results, of course. But if further research can duplicate these findings, then doctors get a new way to potentially track and diagnose the disease. The advance could also give researchers a tool to test Alzheimer's drugs by tracking how the tau protein buildup responds to a given treatment through detailed PET scans. What's more, detailed imaging could lead to earlier diagnosis and treatment, which doctors believe may be the best way to slow Alzheimer's advance.

- here's the Forbes story
- check out the BBC's take
- here's the journal abstract