'Smart cell patch' to control diabetes on its own

Researchers have created a synthetic painless patch filled with natural beta cells that can secrete doses of insulin to control blood sugar levels on demand.

The patch could provide relief to millions of people with Type-1 and advanced Type-2 diabetes who need to monitor insulin levels constantly.

While insulin injections provide painful and often imperfect substitutes, transplants of normal beta cells carry the risk of rejection or side effects from immunosuppressive therapies.

The proof-of-concept builds on an innovative technology, the "smart insulin patch," reported last year in the journal Proceedings of the National Academy of Sciences.

Both patches are thin polymeric squares about the size of a quarter and covered in tiny needles, like a miniature bed of nails.

But whereas the former approach filled these needles with humanmade bubbles of insulin, this new "smart cell patch" integrates the needles with live beta cells.

Tests of this painless patch in animal models of Type-1 diabetes demonstrated that it could quickly respond to skyrocketing blood sugar levels and significantly lower them for 10 hours at a time.

The results were published in the journal Advanced Materials.

"This study provides a potential solution for the tough problem of rejection, which has long plagued studies on pancreatic cell transplants for diabetes," said senior author Zhen Gu, assistant professor in the joint University of North Carolina at Chapel Hill and North Carolina State University department of biomedical engineering.

"Plus it demonstrates that we can build a bridge between the physiological signals within the body and these therapeutic cells outside the body to keep glucose levels under control," Gu noted.

Beta cells typically reside in the pancreas, where they act as the body's natural insulin-producing factories.

In healthy people, they produce, store, and release the hormone insulin to help process sugar that builds up in the bloodstream after a meal.

But in people with diabetes, these cells are either damaged or unable to produce enough insulin to keep blood sugar levels under control.

"Managing diabetes is tough for patients because they have to think about it 24 hours a day, seven days a week, for the rest of their lives," study co-author John Buse, professor of medicine at the University of North Carolina School of Medicine, said.

"These smart insulin approaches are exciting because they hold the promise of giving patients some time off with regards to their diabetes self-care. It would not be a cure but a desperately needed vacation," Buse said.

Diabetes affects more than 387 million people worldwide, and that number is expected to grow to 500 million by the year 2030, the study pointed out.