Stem cells can turn into another type of tissue and potentially cure brain and nerve injuries, but they do not often survive when injected into the body. Researchers from Canada, however, were able to come up with a solution that could help stem cells survive and boost their ability to repair injury.

Molly Shoichet from University of Toronto and colleagues created a hydrogel that acts like a bubble wrap in order to hold cells together while they are being delivered into a transplant site. They found that this hydrogel can efficiently transport stem cells.

In a new study published in the journal Stem Cell Reports on May 14, Shoichet and colleagues also found that the hydrogel can help promote repair, which can be attributed to the component known as hyaluronan that keeps the cells alive.

In two trials, the gel-like biomaterial partially reversed blindness and helped with the recovery of brain from stroke. The researchers were able to do these by encasing stem cells in the hydrogel before transplanting them into the eye and brain of mice, boosting their healing abilities.

For one part of the study, the researchers encapsulated light sensing cells known as photoreceptors that are responsible for eye vision into hydrogel and injected these into the eyes of blind mice. They were able to restore the animals' vision albeit only partially.

"After cell transplantation, our measurements showed that mice with previously no visual function regained approximately 15 percent of their pupillary response," said stem cell biology expert Brian Ballios. "Their eyes are beginning to detect light and respond appropriately."

For the part of the study that involved injecting the stem cells into the brain of mice that suffered from stroke, the researchers found that within weeks after transplantation, there were improvements in the motor coordination of the mice.

The researchers are now interested in carrying out similar experiments on larger animals that have larger brains so they can conduct investigations on how stem cell transplants can contribute to healing a stroke injury.

"Transient disruption of the retinal outer limiting membrane, combined with HAMC delivery, results in significantly improved rod survival and visual function," the researchers reported. "HAMC also improves the distribution, viability, and functional repair of neural stem and progenitor cells (NSCs). The HAMC delivery system improves cell transplantation efficacy in two CNS models, suggesting broad applicability."