In individuals with Type 1 diabetes, the immune system assaults the pancreas, leaving patients without the ability to naturally manage blood sugar.
According to two new studies, published in Nature Medicine and Nature Biotechnology, researchers have developed a way to transplant pancreatic cells, replacing those lost to Type 1 diabetes, and were able to use the technique to temporarily cure the disease in mice.
Individuals with type 1 diabetes currently cope with their condition by carefully keeping track of the sugar in their blood, measuring it many times per day and then injecting themselves with insulin to maintain proper blood sugar amounts. However, precise control of blood sugar is challenging to achieve, and patients face a range of long-term medical complications consequently.
Doctors have been experimenting with ways to transplant health pancreatic cells since the 1980s, but the alginate gels used to encapsulate cells had been causing scarring – rendering the treatment ineffective.
“We decided to take an approach where you cast a very wide net and see what you can catch,” Arturo Vegas, an assistant professor of chemistry at Boston University and author on both studies, said in a statement. “We made all these derivatives of alginate by attaching different small molecules to the polymer chain, in hopes that these small molecule modifications would somehow give it the ability to prevent recognition by the immune system.”
TMTD is the key
After developing a library of almost 800 alginate derivatives, the scientists conducted a number of tests in mice and primates. One of the most promising was a derivative referred to as triazole-thiomorpholine dioxide (TMTD). The study team decided on a species of mice with a strong immune system and inserted human islet cells encapsulated in TMTD into a area of the abdominal cavity referred to as the intraperitoneal space.
A stealth material surface, shown here, has been engineered to provide an “invisibility cloak” against the body’s immune system cells. In this electron microscopy image, you can see the material’s surface topography. (Credit: MIT)
After implantation, the cells instantly started generating insulin as dictated by blood sugar amounts and were able to kept blood sugar in check for the length of the study, more than 170 days.
“The really exciting part of this was being able to show, in an immune-competent mouse, that when encapsulated these cells do survive for a long period of time, at least six months,” said study author Omid Veiseh, a senior postdoc at the Koch Institute and Boston Children’s Hospital. “The cells can sense glucose and secrete insulin in a controlled manner, alleviating the mice’s need for injected insulin.”
The scientists said they now plan to test their new materials in primates, with the purpose of ultimately holding clinical trials in diabetic patients. If successful, this method could mean long-term blood sugar control for individuals with diabetes.
“Being insulin-independent is the goal,” Vegas said. “This would be a state-of-the-art way of doing that, better than any other technology could. Cells are able to detect glucose and release insulin far better than any piece of technology we’ve been able to develop.”
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Feature Image: A glucose-stimulated insulin, derived from stem cells, producing cells. (Credit: MIT)
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