February 21, 2013 | by Darrin Joy
Scientists have taken a major step toward the ability to produce — right inside their lab — the crucial cells that might cure type 1 diabetes. The cells would be transplanted into diabetic patients to produce insulin and regain control of blood sugar levels.
In a study published online ahead of print Feb. 19 in the Proceedings of the National Academy of Sciences, researchers led by City of Hope’s Hsun Teresa Ku, Ph.D., found that stem cells grown in two special gels developed into cells that produce insulin.
“Eventually, if we can find a way to scale up the process, we might be able to create banks of insulin-producing cells,” Ku said. One day, this could even lead to an unlimited supply for transplant into type 1 diabetes patients.
In islet cell transplantation, researchers gather islet cells — the cells that naturally form insulin in the body — from donated pancreases and transplant them into patients with severe type 1 diabetes. This provides a new source of insulin, a hormone the body needs to metabolize the sugar glucose. People with diabetes can’t metabolize glucose, leading to severe and often life-threatening health problems.
The transplant process often requires more than one pancreas to gather enough healthy islet cells. This places a severe limitation on the number of patients who can undergo the potentially lifesaving procedure because donated pancreases are in short supply.
If researchers can find a way to create more insulin-producing cells for transplantation in the lab, they could reduce the transplant process to just one pancreas, giving more patients access to the procedure.
“The process for gathering islet cells from pancreata leaves a lot of extra tissue,” Ku said. From this tissue, researchers can collect stem cells and grow them using the new method. The scientists could generate enough extra insulin-producing cells to meet the patient’s need and then some. Eventually, they hope to provide a limitless supply.
Ku’s team took stem cells from the pancreases of mice and grew them first in dishes containing a substance called Matrigel. Consisting of a gelatinous mixture of proteins, Matrigel partially recreates the environment that surrounds cells in many tissues in the body. The cells can grow more naturally this way than in petri dishes or flasks.
The researchers next transferred the cells from the Matrigel to a unique gel containing a protein called laminin. In this laminin hydrogel, made by scientists at Caltech in Pasadena, Calif., the cells formed colonies that produce insulin.
These colonies could help make islet cell transplantation to cure type 1 diabetes more efficient and effective.
Researchers on the study included Liang Jin, Ph.D., Tao Feng, M.S., Ricardo Zerda, Angela Luo, Jasper Hsu and Arthur D. Riggs, Ph.D., of City of Hope; Alborz Mahdavi, and David A. Tirrell, Ph.D., of Caltech; and Hung Ping Shih, Ph.D., and Maike Sander, M.D., of the University of California, San Diego.
The study was supported by the National Institutes of Health, the Office of Naval Research, the National Science Foundation, the Juvenile Diabetes Research Foundation and the Eugene and Ruth Roberts Summer Student Academy at City of Hope.
NIH Grant #s: DK081587, DK089533, DK078803 and CA33572