Laboratory study tests an islet-cell stent designed for diabetes research

A new study from IO Lab found that an experimental stent containing pancreatic islet cells released more insulin when exposed to higher glucose in a laboratory perfusion system. The study, published in the Journal of Vascular and Interventional Radiology, examines an early device concept for type 1 diabetes research. The findings establish a glucose response under the tested conditions, with substantial work still required before the approach could be considered for patients.

Brandon Gaston and colleagues developed a stent graft with a semipermeable membrane intended to house insulin-producing islets. The proposed design would place those cells within a blood vessel and allow small molecules to cross the membrane. Its intended location is the portal venous system. The published experiments evaluated the device outside the body.

The researchers tested devices containing human or mouse islets in a benchtop flow system. They compared responses to low and high glucose concentrations and measured insulin during a three-hour period. Each experimental condition used four devices. In the human-islet experiments, mean insulin concentration increased from 229 to 300 micro-international units per milliliter under the higher-glucose condition.

That response suggests the cells retained glucose-sensitive insulin secretion while housed in the experimental device. For cell-delivery research, maintaining this function is one necessary step. A device would also need to sustain the cells’ access to oxygen and nutrients, remain compatible with blood flow and work reliably over a much longer period.

The membrane is intended to support immunoisolation, meaning separation of transplanted cells from immune attack. The laboratory findings do not establish that protection in a living recipient. They also do not show that a device could replace injected insulin, prevent diabetes complications or function safely after implantation. The authors identify in vivo testing as a necessary part of further development.

The team also examined flow using computational modeling. Those simulations used idealized conditions, which limits conclusions about how the device would behave in a human blood vessel. Future studies would need to address clotting, local flow changes, immune responses and the durability of islet function.

The study adds a device-based approach to the broader investigation of islet delivery. Its immediate contribution is a laboratory demonstration that cells within the prototype can respond to a glucose challenge. Establishing a clinical role would require evidence that this response persists after implantation and provides a meaningful benefit without unacceptable risks.