May 25, 2015

Making Blind Mice See Is Just the Beginning

Curing blindness in mice is pretty exciting, but it’s not enough for Dr. Brian Ballios. Although Dr. Ballios is pretty ecstatic about his recent discovery, which partially restored vision to blind mice, his ultimate goal is to turn these findings into treatments for people who are living with vision loss. So, even though Dr. Ballios already has his PhD, he is in the process of becoming an ophthalmologist. These combined skills and knowledge are forging his path toward the clinical application of his research.

Last week, Dr. Ballios’ research, which was supported (in part) by Fighting Blindness Canada (FBC), received lots of media attention—perhaps you recall seeing him pictured with a friendly mouse in the Globe & Mail. This is because his collaborative paper, published in Stem Cell Reports, offers a solution to one of the biggest challenges in regenerative medicine: getting transplanted stem cells to stay alive, integrate into the right spot, and then start working.

It’s relatively easy to inject a bunch of stem cells into the eye: The hard part is getting them to stay alive long enough to restore vision. Indeed, this is a problem for regenerative medicine more generally. Lots of people are injecting stem cells into lots of different places, but nobody has found a way to keep these newly injected cells alive. Nobody, that is, until Dr. Ballios’ PhD supervisor, Dr. Molly Shoichet, developed a biomaterial that could be injected in a minimally-invasive fashion into multiple areas of the central nervous system. Dr. Ballios spent much of his PhD developing a derivative of this biomaterial to help specifically with supporting the health of transplanted retinal (eye) and neural (brain) stem cells.

In this paper, he shows that the biomaterial significantly boosts cell survival, which is why the entire regenerative medicine community is excited about the results. Previously, the majority of transplantation studies reported very low cell survival (between 0.04% and 8% on average). Dr. Ballios set out to study the relationship between cell survival and the ability of cells to integrate and function. He discovered that transplanting cells in the biomaterial significantly increased their survival rates (at best, 16% of cells survived). At the same time, using the biomaterial increased the ability of transplanted cells to integrate and function. This was true when retinal cells were transplanted into the eye, but amazingly it was also true when the team used the biomaterial to transplant neural cells into the brain.  This type of proof-of-concept data suggests that this cell delivery vehicle could be used to increase the success of any kind of stem cell transplantation.

Dr. Ballios is careful about over-promising what early studies with stem cells can mean for therapy in the clinic today, but he believes these therapies represent the best hope for vision restoration. We are so glad to be partnering with the new Ontario Institute of Regenerative Medicine to support Dr. Ballios’ research into new regenerative therapies for vision loss.

About the Study

Published online on May 14, 2015 in Stem Cell Reports, the paper is titled “A Hyaluronan-Based Injectable Hydrogel Improves the Survival and Integration of Stem Cell Progeny following Transplantation” and was prepared by Brian Ballios from the University of Toronto in collaboration with Laura Donaldson from McMaster University, and Michael K. Cooke, Brenda L.K. Coles, Cindi Morshead, Derek van der Kooy and Molly Shoichet, all from the University of Toronto.