Two new studies provide important insight into possible new therapy for type 1 diabetes without immunosuppressant drugs.

Researchers from the Massachusetts Institute of Technology (MIT), Boston Children’s Hospital, and several other institutions supported with JDRF funding have shown encapsulated human islet cells transplanted into mice can effectively halt type 1 diabetes (T1D) for up to six months without causing an immune response. The findings are reported in two studies published today in Nature Medicine and Nature Biotechnology.

JDRF played a key role in bringing together the lead researchers in these studies, including senior author Daniel Anderson, Ph.D., the associate professor in MIT’s Department of Chemical Engineering and the Institute for Medical Engineering and Science and a research associate at Boston’s Children Hospital; Robert Langer, Sc.D., the David H. Koch Institute professor at MIT and senior research associate at Boston’s Children Hospital; Jose Oberholzer, M.D., chief of transplantation surgery and director of cell and pancreas transplantation at the University of Illinois Hospital & Health Sciences System; Gordon Weir, M.D., professor at Harvard Medical School and chair of the Diabetes Research and Wellness Foundation at the Joslin Diabetes Center; Dale Greiner, Ph.D., professor at the University of Massachusetts Medical School; and Douglas Melton, Ph.D., the Xander University Professor at Harvard University, investigator at the Howard Hughes Medical Institute, and co-director of Harvard’s Stem Cell Institute.

The Nature Biotechnology study details a newly modified alginate material designed to encapsulate human pancreatic islet cells. Alginate, a material originally derived from brown algae, has previously been used to encapsulate cells without harming them or preventing them from sensing and responding to biological signals (for example, by releasing insulin). However, an immune response leads to the build-up of scar tissue around the unmodified alginate capsules over time, making them ineffective.

The MIT researchers aimed to modify alginate to prevent it from triggering this immune response. They created a library of nearly 800 alginate derivatives and evaluated the immune response to each of them, ultimately focusing on one called triazole-thiomorpholine dioxide (TMTD), which provoked minimal immune response in mice and large animal models.

The researchers then implanted human islet cells encapsulated in TMTD in mice with a strong immune system in a further study described in the second paper in Nature Medicine. The cells used in the study were generated from human stem cells developed by Douglas Melton. Following implantation, the cells immediately began producing insulin in response to blood glucose levels and were able to maintain blood glucose within a healthy range for 174 days, the length of the study.

“Encapsulation therapies have the potential to be groundbreaking for people with T1D. These treatments aim to effectively establish long-term insulin independence and eliminate the daily burden of managing the disease for months, possibly years, at a time without the need for immune suppression,” said JDRF Vice President of Discovery Research Julia Greenstein.

“JDRF is excited by these findings and we hope to see this research progress into human clinical trials and ultimately a potential new T1D therapy,” she said.

“We are excited by these results, and are working hard to advance this technology to the clinic,” said Dr. Anderson, senior author on the papers.

JDRF created the Encapsulation Consortium in 2013, jump-starting the field by encouraging collaboration among its more than 25 members and shaping a strategy to guide research. The ultimate goal of the Consortium is to develop products that will hide implanted beta cells from the immune system or cause the immune system to accept the cells while also providing an environment in which the cells can produce sufficient insulin for managing blood sugar in people with T1D.

T1D is a chronic, life-threatening autoimmune disease that strikes children and adults at any age. In T1D, the immune system destroys the cells that produce insulin, eventually eliminating the body’s ability to self-regulate blood sugar. To survive, people with T1D must test their blood-sugar levels throughout the day by either pricking their fingers to draw blood or using a continuous glucose monitor, and then administer insulin through multiple daily injections or the use of an infusion insulin pump.

JDRF helped to fund these studies in collaboration with The Leona M. and Harry B. Helmsley Charitable Trust.