Camillo Ricordi, MD, FNAI, describes the process of islet transplantation and how it can benefit individuals with type 1 diabetes.
Islet transplantation allows the liver to complete both its normal functions and those of the endocrine pancreas, said Camillo Ricordi, MD, FNAI, a professor and director of the Diabetes Research Institute and Cell Transplant Center at the University of Miami, Florida. Ricordi's talk "The Status of Islet Transplantation in the U.S." was presented at the American Diabetes Association's 81st Scientific Sessions.
Can you introduce yourself and describe the work you do?
My name is Camillo Ricordi. I'm a professor and director of the Diabetes Research Institute and Cell Transplant Center at the University of Miami. My work, since I begin my career over 4 decades ago, has been based on pancreatic islet cell processing, transplantation, and cellular therapies for diabetes, from pancreatic islets to mesenchymal stem cells to try to intercept and halt the progression of autoimmunity or to treat long-term subjects with type 1 diabetes and prevent the progression of complications of the disease: nephropathy, neuropathy, and retinopathy. Basically, we've been involved with cell processing, tissue processing, and cell therapies and regenerative medicine.
Can you give a brief overview of islet transplantation and explain why it is beneficial for patients with type 1 diabetes?
Islet transplantation is the technology by which you process a human pancreas [and] extract the insulin-producing cells that are contained in this micro-organ, called pancreatic islets, which comprise of thousands of cells of different types, endocrine cells, insulin-producing cells, pericytes, stromal vascular fraction, mesenchymal stem cells, endothelial. This micro-organ is a very complex, integrated system that you have to transplant as a micro-organ, not as a single cell, because previous attempts, decades ago, where [they] transplanted just beta cells or the insulin-producing cells would not work as well as an integrated endocrine micro-organ with many different cell types, including the vasculature inside the islets that contributes to the neovascularization of the islets after transplantation.
In a way, they are like mini organ transplants, with the difference that we don't have an anastomosis but after the transplant. We let the new blood vessel co-integrate with the vessels from the islets and restore the vascular supply of this micro-organ. Typically, these cells have been transplanted inside the liver via a portal vein infusion, like a blood transfusion to the liver where they remain trapped. Being micro-organs, if they would be single-celled, they would pass through, but they instead remain trapped in the micro-vasculature of the liver where they get revascularized and they start producing insulin and doing the normal function that they generally do in the pancreas. If you wish, [we're] re-engineering the liver to become a double organ that does both the function of the liver and that of the endocrine pancreas. That, in a nutshell, is what islet transportation is.