Finding molecular signatures of Alzheimer’s disease in blood extracellular vesicles
No blood tests currently exist that can detect brain disorders like Alzheimer’s disease (AD) at an early stage or monitor the effectiveness of therapeutic interventions.
IRP researchers led by Dimitrios Kapogiannis, M.D., found that extracellular vesicles, believed to be released from nerve cells, can be isolated from blood samples. The team found that subjects with mild cognitive impairment and AD exhibit major abnormalities in the amounts of several proteins within extracellular vesicles; these proteins were already known to be involved in brain dysfunction and AD. Preliminary studies suggest that these abnormalities may be present up to 10 years before patients are formally diagnosed with the disease.
The findings, if confirmed in larger studies currently underway, suggest that neuron-derived extracellular vesicles circulating in the blood can identify individuals who will develop AD before the onset of symptoms.
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