Hydrogels boost ability of stem cells to restore eyesight and heal brains

University of Toronto researchers show that engineered ‘hydrogels’ not only help with stem cell transplantation, but actually speed healing in both the eye and brain

Toronto scientists and engineers have made a breakthrough in cell transplantation using a gel-like biomaterial that keeps cells alive and helps them integrate better into tissue. In two early lab trials, this has already shown to partially reverse blindness and help the brain recover from stroke.

Led by University of Toronto professors Molly Shoichet (ChemE, IBBME) and Derek van der Kooy, together with Professor Cindi Morshead, the team encased stem cells in a hydrogel that boosted their healing abilities when transplanted into both the eye and the brain. These findings are part of an ongoing effort to develop new therapies to repair nerve damage caused by a disease or injury.

Conducted through the U of T’s Donnelly Centre for Cellular and Biomolecular Research, their research was published in today’s issue of Stem Cell Reports, the official scientific journal of the International Society for Stem Cell Research.

Stem cells hold great therapeutic promise because of their ability to turn into any cell type in the body, including their potential to generate replacement tissues and organs. While scientists are adept at growing stem cells in a lab dish, once these cells are on their own—transplanted into a desired spot in the body—they have trouble thriving. The new environment is complex and poorly understood, and implanted stem cells often die or don’t integrate properly into the surrounding tissue.

Shoichet, a bioengineer who recently won the prestigious L’Oreal-UNESCO for Women in Science Award, and her team created the hydrogel several years ago as a kind of a bubble wrap to hold cells together during transport and delivery into a transplant site.

“This study goes one step further, showing that the hydrogels do more than just hold stem cells together; they directly promote stem cell survival and integration. This brings stem-cell based therapy closer to reality” says Shoichet, whose affiliations span the Donnelly Centre, the Department of Chemical Engineering and Applied Chemistry and the Institute of Biomaterials & Biomedical Engineering at U of T.

Restoring partial vision

In addition to examining how the stem cells benefit from life in hydrogels, the researchers also showed that these new cells could help restore function that was lost due to damage or disease.

One part of the Stem Cell Reports study involved the team injecting hydrogel-encapsulated photoreceptors, grown from stem cells, into the eyes of blind mice. Photoreceptors are the light sensing cells responsible for vision in the eye. With increased cell survival and integration in the stem cells, they were able to partially restore vision.

Read more: Hydrogels boost ability of stem cells to restore eyesight and heal brains