Sowmya Viswanathan, PhD, University Health Network

Getting it right for osteoarthritis cell therapy

More than five million Canadians over the age of 15 are affected by osteoarthritis. There is tremendous promise for stem cell-based therapies to reduce the burden of this disease but bringing these therapies to the clinic involves validating their safety and efficacy through clinical trials first. To this end, more than 28 clinical trials have been initiated worldwide using mesenchymal stromal cells (MSCs), which are similar to stem cells, capable of forming cartilage, bone and other types of cells.

One of the questions these trials are seeking to answer is how many MSCs would make the best dose? Early-phase clinical trials evaluate dosage as part of their safety testing and will typically increase the number of active cells as the trial progresses to find the optimal amount. But getting it right means knowing how many of the therapeutic cells survive, how long they survive, and where they might migrate to after injection.

Dr. Sowmya Viswanathan, a researcher with the University Health Network in Toronto, is working on an innovative method to get these answers. In 2016, she received an Impact award from the Stem Cell Network to fine-tune a method of tracking cells. Viswanathan’s team successfully tagged MSCs with iron nanoparticles, which allow the cells to be imaged and therefore followed for migration within the tissues and for cell survival. Iron is naturally present in the body but was further tested by the team to verify its safety as a tracking device.

Thanks to the SCN award, Viswanathan can now use these tagged cells as part of the next phase of osteoarthritis clinical trials currently being co-led by her and Dr. Jas Chahal at Toronto Western Hospital. The information gathered from the research will be extremely useful as they identify the safest and most efficacious dose. Not only will this be a critical step in moving osteoarthritis cell therapies to the clinic but the availability of tagged cells could also have wide-ranging application for clinical trials using MSCs for a range of other conditions.

Project Outcomes

• Important data and safety measurements collected to inform clinical trial application to Health Canada
• New national and international collaborations initiated