Beta Cell Replacement

Development of methods to create insulin-producing beta cells for transplantation in abundant quantities, enough to treat all, as well as development of technologies to keep the transplanted cells alive and protect them from immune system attacks. Reprogramming of other cells in the body into insulin-producing cells.

Status

  • It is now possible to create insulin-producing beta cells from stem cells.

  • Technology for manufacturing in large quantities is under development by several companies.

  • Insulin-producing beta cells can further be extracted from animals (xenotransplantation), a possibility that is still being researched.

  • The cells can be transplanted encapsulated, individually or in large quantities, so that they avoid attacks by the immune system, but problems with adequate oxygen and nutrient supply, as well as the formation of scar tissue, make the time between replacement of the cells too short.

  • Research is being carried out to develop better encapsulation devices enabling the transplanted cells to live better and longer.

  • Human alpha cells can be reprogrammed into functioning insulin-producing cells in mouse experiments.

Transplantation

Transplantation of insulin-producing cells is an obvious, but challenging, way to cure type 1 diabetes, and research has been going on for many years. There are basically 3 methods, but only transplantation of encapsulated beta cells has the potential to cure everyone with type 1 diabetes.

Pancreas Transplantation

With developments in pancreas transplantation, operations can now be performed more safely and with better results than earlier.

However, it is important to emphasize that pancreas transplantation is not a cure for people with type 1 diabetes, with the exception of a small minority of patients who, typically, have developed severe diabetic kidney disease. Because:

  • The pancreata used for transplantation come from organ donors, ie. healthy people who have died in traffic accidents, etc., and has agreed to organ donation. Thus, in most countries, pancreata would be available for less than 1% of people with type 1 diabetes.

  • Although surgical and medical advances have made the operation safer, it is still a complicated and dangerous operation. Typically, it is therefore offered only in connection with a kidney transplant and only to patients whose quality of life is severely impaired due to the disease.

  • The body sees a transplanted pancreas as a foreign body, and patients have to take strong immunosuppressive drugs for life, to avoid rejection of the transplanted pancreas. These drugs can have major side effects, such as lower resistance to bacterial and viral infections and cancer.

Islet Cell Transplantation

Transplantation of the islets of Langerhans is not transplantation of an entire organ, but just of the insulin-producing pancreatic islet cells. The surgical operation is significantly smaller than pancreas transplantation, but unfortunately, adequate insulin production is typically achieved only for a shorter time. Islet cell transplantation is relatively uncomplicated and harmless, but the limitations described in points 1 and 3 under pancreas transplantation, apply for this type of transplant as well, which is why this form of transplantation too, only helps a limited number of type 1 diabetes patients.

Transplantation of Encapsulated Beta Cells

This type of transplant has the potential to cure anyone with type 1 diabetes, and both academia and industry have a sharp focus on developing the technology.

The principle is to replace the cells that have been destroyed by the immune system in type 1 diabetes with cells from an external source. To protect the new cells from the immune system attack, without the use of immunosuppressive drugs, they are encapsulated, either individually (microencapsulation), or grouped together in a container (microencapsulation). The encapsulation consists of a porous membrane, with meshes large enough for insulin to flow out and nutrients for the cells to flow in, but too small for the immune system's killer T-cells to get in.

Production lines to generate insulin-producing beta cells for transplantation in abundant quantities to treat all people with type 1 diabetes must be developed, as well as stable encapsulation technologies to keep the transplanted cells alive and protect them from the immune system attack.