Islet cell transplantation along with blood vessel cells can successfully treat type 1 diabetes

The use of engineered human blood vessel-forming cells in pancreatic islet transplants increased the survival of insulin-producing cells and promoted a cure for diabetes in a preclinical study led by scientists at Weill Cornell Medicine. The new approach, which requires further development and testing, may allow much wider use of islet transplantation for diabetes treatment in the future.

An islet, located in the pancreas, is a cluster of insulin-secreting and other cells surrounded by tiny specialized blood vessels. In type 1 diabetes, which affects about nine million people worldwide, insulin cells are killed by an autoimmune process. Although islet transplantation is a promising approach to treating such cases, the only FDA-approved method to date has significant limitations.

In a study published in the journal Science Advances, scientists have shown that the special blood vessel-forming cells they developed, called “reprogrammed vascular endothelial cells” (R-VECs), can overcome some of these limitations by providing robust support for islets, allowing them to survive and permanently control diabetes when transplanted under the skin of mice.

“This work lays the foundation for subcutaneous transplantation of islets as a relatively safe and long-lasting treatment for type 1 diabetes,” said study lead author Dr. Ge Li, a postdoctoral fellow in Dr. Shaheen Rafii’s lab.

The currently approved method of islet transplantation involves the islets being injected into a vein in the liver. This invasive procedure requires long-term administration of immunosuppressive drugs to prevent islet rejection, involves relatively uncontrolled islet dispersal, and usually loses efficacy within a few years, probably in part due to a lack of adequate supporting cells.

Ideally, scientists want a method that allows islets to be implanted in a more controlled and accessible location, such as under the skin, and allows the transplanted tissue to survive indefinitely. The researchers also hope to eventually circumvent the problem of immune rejection by using islets and endothelial cells derived from patients’ own cells or engineered to be invisible to the immune system.

In a new study, scientists have demonstrated the feasibility of long-term subcutaneous transplantation of islets using R-VECs as essential support cells. “We have shown that vascularized human islets implanted into the subcutaneous tissue of immunodeficient mice are rapidly connected to the host bloodstream, providing immediate nutrition and oxygen, thereby enhancing the survival and functionality of vulnerable islets,” says Dr. Rafii.

Indeed, derived from human umbilical vein cells, R-VECs are relatively durable when transplanted – unlike the fragile endothelial cells found in islets – and are designed to adapt well to support any specific tissue type surrounding them.

Remarkably, when co-transplanted with islets, the scientists found that R-VECs actually adapted, supporting the islets with a rich meshwork of new blood vessels and even acquiring the “signature” gene activity of natural islet endothelial cells.

A large majority of diabetic mice that received islets plus R-VEC transplantation regained normal body weight and exhibited normal blood glucose control even after 20 weeks, a time frame that for this mouse model of diabetes indicates effective permanent engraftment of islets. Mice that received islets but did not receive R-VEC did much worse.

In their study, the team showed that the combination of islet cells and R-VECs could also successfully grow into small “microfluidic” devices that could be used to rapidly test potential diabetes drugs.

Ultimately, the potential for surgical implantation of these vascularized islets should be studied for safety and efficacy in large animal models.

Shalimov National Institute of Surgery and Transplantology Ukraine,KyivLeave a request

Hisar Hospital Intercontinental Turkey,IstanbulLeave a request

Apollo Hospitals India,Delhi 5.00 (1 review)Leave a request

Published: 26.02.2025

Updated: 24.02.2025

Medical author, Medical editor:

Stepan Yuk

Medical expert:

PhD. Olexandr Voznyak