A recent study led by researchers from the University of California- Los Angeles Health Sciences (UCLA) determined the COVID-19-derived protein-induced running fluid through a 3D printed model to explain how the virus increases the risk of stroke.
COVID-19 was initially identified as a disease with severe respiratory symptoms, but little is known about how it increases the risk of stroke.
To reinforce the findings, UCLA researchers used a 3D-printed silicone model of blood vessels in the brain to report the forces generated by blood pushing through an abnormally narrowed artery, a condition known as intracranial atherosclerosis. They showed how these forces work on the cells lining the arteries, and increase molecular production called angiotensin-converting enzyme 2, or ACE2, which the coronavirus uses to to enter cells on the surface of blood vessels.
Dr. Jason Hinman, assistant professor of neurology at UCLA’s David Geffen School of Medicine and senior author of the study, said the flow directly affects ACE2 expression. In addition to Hinman, the study’s authors are neurologists at Geffen School of Medicine and scientists from UC San Francisco and the Veterans Health Administration. The paper was published (PDF) in Stroke.
UCLA researchers created the model using data from CT scans of blood vessels in the human brain. They would then line the inner surface of the modules with endothelial cells, the type of cells that line human blood vessels. The models allowed the researchers to use the same forces that would work on real blood vessels during COVID-19 infection.
To test whether a bobav coronavirus in the bloodstream could capture the ACE2 on the endothelial cells in the brain, researchers fabricated fat molecules ‘viruses’ with the spike proteins that coronavirus uses to bind to ACE2. Previous research has shown that the coronavirus binds to endothelial cells in other organs, but it was not known if this also occurred in the brain.
After creating the new model, researchers confirmed that the granules actually interacted with the cells lining the blood vessel, mostly in areas of the brain with higher levels. of ACE2.
“This finding could explain the increased incidence of strokes seen in COVID-19 infections,” Hinman said.
Another finding shows that when the scientists analyzed which genes were turned on in the endothelial cells after attaching the spike coronavirus proteins, they found that the implanted genes act as a specific set of immune response genes found in the blood of brain cells, but not in endothelial cells from other organs of the body.
“There is a brain-specific endothelial response to the virus that may be helpful in identifying patients at higher risk for stroke,” Hinman said.
The researchers plan to conduct follow-up studies using live coronavirus in the 3D printed blood vessel model, which would further validate the results of the current study and clarify which COVID-19 patients are may be at higher risk for stroke.