Scientists developed a new implantable device called SHEATH (Subcutaneous Host-Enabled Alginate THread) that may revolutionize insulin delivery for Type 1 diabetics. The thread-like implant is installed in a two-step process, leading to the deployment of “islet devices” derived from insulin-producing cells in the body.
The scientists inserted nylon catheters under the skin, which remain for up to six weeks. Blood vessels form around the catheters, providing structural support for the islet devices placed in the space when the catheter is removed. The 10-centimeter-long islet devices secrete insulin via islet cells and receive nutrients and oxygen from blood vessels to sustain them.
Researchers at Cornell and the University of Alberta designed and tested the implantation technique. Professor Minglin Ma of Cornell created an implantable polymer in 2017, and his team developed an even more advanced version in 2021 that demonstrated the ability to control blood sugar levels in mice for six months.
However, the long-term application of SHEATH in patients remains a challenge. Maintaining the functionality of islet devices inside the body is difficult due to the blocking of blood vessels. The researchers are working on optimizing the exchange of nutrients and oxygen in large animal models and eventually in patients. Despite the current limitations, the implant has the potential to replace the standard treatment for Type 1 diabetes, which involves daily injections or insulin pumps.