Sticky plaques of proteins called amyloids mark several different, though related degenerative brain diseases including Alzheimer’s, Parkinson’s and Creutzfeld-Jacobs. The symptoms of these disorders overlap and methods to diagnose and monitor them are not very advanced.
To solve this problem, scientists have devised several new fluorescent probes that change color depending on what type of amyloid they encounter. Because amyloids accumulate in the eye as well as the brain, their discovery offers hope that one day neurodegenerative diseases could be differentially diagnosed with simple eye drops or ointment and an eye exam.
“The key trick here is that the small differences in the proteins that make up different forms of amyloid interact differently with our fluorescent probes to result in measurably different colors of the emitted light,” said one of the researchers.
The colors vary depending on the physical properties of pockets in the different amyloid proteins. The team demonstrated that one of their probes glows yellow when marking amyloid deposits associated with prion disease, and green when it binds to amyloids associated with Alzheimer’s disease in tissue samples, for example.
Among the few available diagnostics for Alzheimer’s disease are radioactive molecules that target amyloid, which can be detected in the brain using positron emission tomography or PET scans. But that test only says whether amyloid has formed in the brain without distinguishing between the various types.
Now that they have learned how physical properties of amyloid control the colors of their markers, they are expanding their catalog to create probes for discriminating between other forms of amyloid.
The technology has been licensed for commercial development of diagnostic tests for human neural disease.
This story is reprinted from material from UC San Diego, with editorial changes made by Materials Today. The views expressed in this article do not necessarily represent those of Elsevier. Link to original source.