The University of British Columbia and Vancouver Coastal Health are testing a radical way to cure diabetes. The researchers are implanting pancreatic cells grown in a lab from embryonic stem cells to replace ones previously damaged. The hope is that the implanted cells would mature and multiply to eradicate the reliance on insulin and everyday monitoring of blood sugar via finger pricking.
“If these replacement cells restore a person’s ability to produce their own insulin when needed, it would prevent dangerous episodes of low blood sugar and lessen the complications resulting from high blood sugar, such as blindness, heart attacks and kidney failure,” says Dr. David Thompson, a principal investigator in the clinical trial, a UBC clinical assistant professor of endocrinology and medical director of the Vancouver General Hospital Diabetes Centre. “Eventually, it might even free people from a lifetime of constantly checking their blood sugar and injecting themselves, transforming treatment of this disease into a more manageable condition.”
The trial could involve about 10 or more people in Vancouver with a severe form of type 1 diabetes, in which a person’s immune system attacks the pancreas, degrading or eliminating its ability to produce insulin.
The team received a grant from the Stem Cell Network of Canada for $500,000 to implement these treatments. Currently, they have only implanted one person, but intend to implant more in the coming weeks. Participants will be followed for two years to see if the implanted cells mature into insulin-producing beta cells and other cells capable of controlling a person’s blood sugar, and whether there are significant side effects.
The implants are part of a larger clinical study by ViaCyte that plans to test the cell-replacement therapy on approximately 40 patients between the US and Canada. ViaCyte has developed a technique for coaxing the embryonic cells along a path to become mature pancreatic cells. The company has also developed for the clinical trial, a protective packet – smaller than a VISA card – that will be implanted just beneath the skin. The packet’s membrane will allow blood vessels to permeate inside so that oxygen and other nutrients will stimulate them to differentiate further. The researchers expect some of the cells will become beta cells, which sense blood sugar levels and release insulin when needed.
As well as these packets, other smaller “sentinel” packets will be implanted and taken out at an earlier stage to evaluate the condition and the development of the cells inside.
With the intention to prevent the participants’’ bodies from rejecting the units, they will be taking immunosuppressants. This, however, makes the patients more susceptible to other infections and is therefore only being clinically tested on people who have a particularly dangerous form of type 1 diabetes.
The procedure for implanting the cells, performed by a team led by Dr. Garth Warnock, a UBC surgery professor, is similar to transplanting clusters of beta cells, known as “islets,” from deceased donors – a treatment pioneered at the University of Alberta. If this clinical study is successful, it could be a promising lead to a cure for type 1 diabetes.