Scientists continue to break new ground in the realm of cellular reprogramming, a burgeoning area of medical research where one type of cell is retrained to fulfill the role of another. A team at Ohio State University (OSU) has leveraged this technology to repair damaged tissue in mice with stroke-affected brains, a technique it hopes could one day help restore speech and motor function in human victims of the injury.
Time is of the essence in the event of a stroke, where the supply of blood to the brain is suddenly disrupted, most often caused by an arterial blockage. These are known as ischemic strokes, and treatments are available to break apart the clots that form and block the arteries, but need to be administered within hours to be effective and avoid long-lasting damage to brain tissue.
This long-lasting damage includes impaired speech and motor and cognitive function, and as it stands there are no treatments available for these lingering effects. The OSU team sought to tackle this problem by using skin cells as its starting point. The scientists used a technique they call tissue nanotransfection, where genetic material is introduced into the cells, which retrains them to become vascular cells.
“We can rewrite the genetic code of skin cells so that they can become blood vessel cells,” said Daniel Gallego-Perez, who led the research team. “When they’re deployed into the brain, they’re able to grow new, healthy vascular tissue to restore normal blood supply and aid in the repair of damaged brain tissue.”
The team observed this phenomenon when the retrained cells were injected into the brains of stroke-affected mice, where they were found to drive the development of new blood vessels. This had the effect of promoting healthy blood supply and repairing the damaged tissue, with the mice receiving the treatment regaining 90 percent of their motor function. MRI scans shows areas of the brain that had been damaged were repaired in the space of a few weeks.
“We found that the mice have a higher recovery because the cells that are being injected into the affected area also release healing signals in the form of vesicles that help in the recovery of damaged brain tissue” said Natalia Higuita Castro, co-lead author on the study.
The treatment is a long way from reaching humans, but the researchers will build on these early promising results with further investigations into how it can treat the persistent effects of ischemic stroke. They also believe it could one day be used to treat other brain disorders such as Alzheimer's and autoimmune diseases.
“The thought was that once brain tissue dies, that was it,” said Dr. Shahid Nimjee, a neurosurgeon at Ohio State University Medical Center and co-author of the study. “We’re now learning that there’s opportunities where we can regenerate cells to restore function to the brain.”
The video below provides an overview of the research, while the published paper can be viewed in the journal Science Advances.
Source: Ohio State University