2019 Alzheimer's Association Research Grant (AARG)

Exosomes as Diagnostic Tools for Alzheimer´s disease - EXO_DIAG_AD

Can measuring proteins in blood help diagnose Alzheimer’s disease?
 

Ana Gabriela Henriques, Ph.D.
University of Aveiro
Aveiro, Portugal

Background

One way cells share materials and communicate is by producing small, fluid-filled spheres known as exosomes. Exosomes released by cells can be absorbed by other cells, allowing materials to be transported between cells. Recent studies have shown that exosomes may be a source of a variety of biological markers (biomarkers), including proteins that are “biomarkers” of disease.
 
Studies show that if abnormal levels of beta-amyloid or tau protein—the two main hallmark brain changes  of Alzheimer’s—are found in exosomes, it could indicate early brain changes seen in Alzheimer’s. Exosomes are found in readily accessible biological fluids, such as blood and urine. Dr. Ana Gabriela Henriques believes that analyzing exosomes found in blood could represent a new, accessible approach to diagnosing or monitoring brain changes in Alzheimer’s.
 

Research Plan

The researchers will analyze blood samples collected as part of the existing studies at the University of Aveiro in Portugal and the University Medical Center of Göttingen in Germany. They will isolate exosomes from the blood samples and measure their contents. Dr. Henriques’ team will examine whether exosomes collected from blood samples contain known Alzheimer’s biomarkers including levels of beta-amyloid and abnormal tau protein.  The researchers will also look for other relevant proteins (such as BACE-1 or amyloid precursor protein, the parent protein of beta-amyloid) in the exosomes.  By measuring many different proteins in the exosomes, Dr. Henriques’ team believes that they may be able to identify a biomarker “signature” inside exosomes that distinguishes Alzheimer’s from other brain diseases.
 
Then, Dr. Henriques’ team will perform statistical analyses to determine whether exosomes collected from blood are able to accurately identify individuals with Alzheimer’s related brain changes.
 

Impact

If successful, this study could represent an important step towards developing a potentially inexpensive and minimally invasive strategy to help diagnose Alzheimer’s. Families facing Alzheimer’s now and in the future will benefit greatly from early detection, allowing for important care and planning. Furthermore, when we have new therapies, we will be in a better position to know who needs treatment at the earliest time point.