Detecting dementia in the blood
New diagnostics for Alzheimer's?

Date:
September 27, 2021
Source:
Swiss Federal Laboratories for Materials Science and Technology
(EMPA)
Summary:
Researchers want to image proteins with unprecedented precision
-- and thus gain insights into the molecular pathogenesis of
Alzheimer's. This should pave the way for an earlier diagnosis of
the dementia disorder via a simple blood test. A successful pilot
study has now been completed.



FULL STORY ==========================================================================
If the suspicion of Alzheimer's disease creeps up, those affected must
prepare themselves for lengthy and complex procedures until the case is
clear. A team from Empa and the Cantonal Hospital of St. Gallen is now
in the process of developing a blood test that will enable a reliable
diagnosis using atomic force microscopy (AFM). The researchers have
recently published their first results of a successful pilot study in
the journal Science Advances.


==========================================================================
A deep look into the molecular universe In the beginning, physicist Peter Nirmalraj wanted to understand the molecular pathogenesis of Alzheimer's
in order to enable new approaches in diagnostics and therapy. One step
further would be to decipher the exact role of beta- amyloid peptides
and tau proteins associated with the neurodegenerative disease. Nirmalraj therefore set out not only to detect the mere presence of the suspicious proteins, but also to determine their variable shape and form as well
as their amounts.

Current methods allow the determination of the total amount of both
proteins in body fluids. However, these techniques do not allow the visualization of differences in the shape and condition of protein accumulations. The researcher is therefore working on technologies that
allow nanometer-scale observations in blood and yet do not destroy the structure and morphology of the proteins.

Together with neurologists at the Cantonal Hospital in St. Gallen,
Nirmalraj has now successfully completed an initial study. For their
pilot study, he examined blood samples from 50 patients and 16 healthy subjects. Using AFM technology, the Empa researcher analyzed the surface
of around 1000 red blood cells per person without knowing anything
about their state of health. "This was the only way to make sure the interpretation of the data remained objective," says Nirmalraj.

Protein fibers as an indicator The Empa researcher measured the size,
structure and texture of protein accumulations found on the blood
cells. After thousands of red blood cells, the team eagerly awaited the comparison of the results from Nirmalraj's counts with the clinical
data from the neurologists. And indeed, the researchers were able to
discern a pattern that matched the patients' disease stage: People who
had Alzheimer's disease had large amounts of protein fibers made up of beta-amyloid peptides and tau proteins. The proteins were able to assemble
into fibers several hundred nanometers long. In healthy individuals or
those with incipient brain disorders, however, Nirmalraj counted only
few fibers.

This proves the feasibility of blood analysis using AFM technology, the
Empa researcher says: "If a reliable blood test can be developed based
on this method, people with suspected Alzheimer's would be spared the unpleasant puncture of the spinal canal in order to be able to diagnose
the disease reliably." However, there is still a long way to go before
a simple blood test is available in hospitals. The team's next step
is to corroborate the data by studying a larger number of subjects at
different stages of the disease using AFM and chemical analysis.

========================================================================== Story Source: Materials provided by Swiss_Federal_Laboratories_for_Materials_Science_and
Technology_(EMPA). Note: Content may be edited for style and length.


========================================================================== Journal Reference:
1. Peter Niraj Nirmalraj, Thomas Schneider, Ansgar Felbecker. Spatial
organization of protein aggregates on red blood cells as physical
biomarkers of Alzheimer's disease pathology. Science Advances,
2021; 7 (39) DOI: 10.1126/sciadv.abj2137 ==========================================================================

Link to news story: https://www.sciencedaily.com/releases/2021/09/210927132042.htm

--- up 3 weeks, 4 days, 8 hours, 25 minutes
* Origin: -=> Castle Rock BBS <=- Now Husky HPT Powered! (1:317/3)