New beta cells have been grown, implanted and housed inside a tiny ‘shark cage’ like device in mice as part of a research trial conducted in the United States. The cage helps maintain insulin levels by protecting the cells from the animals’ immune system.

The immune system mistakenly attacks beta cells in the pancreas in people living with type 1 diabetes which decreases insulin production and reduces their ability to manage blood glucose levels. This means regular insulin injections are required to manage the chronic condition.

Researchers from Washington University and Cornell University collaborated to develop a device that protects the implanted beta cells, while still allowing them to function properly.

In previous studies, the newly implanted beta cells were attacked by their immune system, so researchers had to suppress the animals’ immune system, which is a dangerous step for human use.

The cage like device is made up of hydrogel core that contains the beta cells, wrapped in porous skin of nanofibers. The pores are large enough for the insulin to escape, but too small for immune cells to enter.

“One of the challenges in this scenario is to protect the cells inside of the implant without starving them,” says Jeffrey Millman, co-senior author of the study.

“They still need nutrients and oxygen from the blood to stay alive. With this device, we seem to have made something in what you might call a Goldilocks zone, where the cells could feel just right inside the device and remain healthy and functional, releasing insulin in response to blood sugar levels.”

For up to 200 days, the cells in the implants remained functional, and the animals’ diabetes was well managed for that whole time.

“We’d rather not have to suppress someone’s immune system with drugs, because that would make the patient vulnerable to infections,” says Millman.

“The device we used in these experiments protected the implanted cells from the mice’s immune systems, and we believe similar devices could work the same way in people with insulin-dependent diabetes.”

The research was published in the journal Science Translational Medicine.

Key points

• ‘Shark cage’ like devices protect beta cells from animals’ immune system.
• Beta cells help maintain insulin levels in mice with diabetes.
• Hopes the trial will help people with type 1 diabetes.