Neuroscientists have discovered the potential next step in stroke therapy, after finding that blood replacement therapy leads to improved stroke outcomes in mice.
The procedure would involve replacing the blood of a stroke patient with the blood of a healthy person who’s never suffered a stroke. This could lessen brain damage and avoid any neurological injury.
The researchers, from West Virginia University, found that blood substitution therapy preserved the brains of mice from stroke damage. Replacing 20 percent of a mouse’s blood showed a profound reduction in brain damage.
Currently, the only treatment following a stroke is medication that dissolves the clot and improves blood flow, but it typically needs to be administered within three hours of the stroke. This blood transfusion treatment, however, could take place up to seven hours after a stroke and still have benefits.
Xuefang Ren, research assistant professor at West Virginia University’s Department of Neuroscience, led the study, which is published in the journal Nature Communications.
“We were able to demonstrate that if you remove part of the blood from a subject undergoing stroke, and replace that blood from a subject that’s never had a stroke, the outcomes of that stroke are profoundly improved,” said Ren.
The idea of the treatment is that it dampens the body’s immune response after a stroke, which actually exacerbates brain damage.
The researchers found that blood replacement therapy removes inflammatory cells and decreases levels of neutrophils, a type of white blood cell that helps lead the immune system’s response and enzyme MMP-9, which can lead to blood-brain barrier leakage and degeneration in brain tissue, following a stroke.
“The immune system doesn’t recognise much of what’s happening when there’s a stroke,” says co-author James Simpkins, director of the Center for Basic & Translational Stroke Research.
“So the neutrophils go to the brain and try to clean up the damage that happens. But there’s too much in the brain and those same neutrophils release MMP-9, which then exacerbates the damage.”
“Stroke is simply not a cerebral vascular event, it’s a whole-body event. Both the brain and the body get signals that something’s going on in the brain and as the immune system responds to try to help, it actually worsens the outcome. Therefore, by removing the blood and replacing it with the blood of those that have not experienced stroke, we get good outcomes.”
The researchers hope that this treatment could reduce the number of deaths among stroke patients.
