A type 1 diabetic patient treated in a clinical trial at The Diabetes Research Institute (DRI; a Center of Excellence at the University of Miami Miller School of Medicine) no longer needs insulin injections to manage her diabetes. For the first time in 26 years, Wendy Peacock, of San Antonio, Texas, is producing her own insulin from an implanted engineered pancreas.
“We’re quite excited. This has been the best outcome we have seen at this stage,” said Rodolfo Alejandro, MD, Professor of Medicine and Director of the DRI Clinical Cell Transplant Program, in a news release. “It’s a unique site, the surgery is very simple and the patient recovers very quickly. We will continue until our final goal – islet transplantation without immunosuppression.”
Peacock was the first patient to receive the preclinical version of the DRI BioHub. This “bioengineered mini-organ”, designed to mimic the native pancreas, is composed of insulin-producing islet cells embedded in a biological scaffold. The scaffold was implanted on Peacock’s omentum, the highly vascularized layer of tissue covering the abdominal organs.
“This was the first tissue engineered islet transplant using a ‘biodegradable scaffold’ implanted on the surface of the omentum,” said Camillo Ricordi, MD, Director of the DRI and the DRI’s Cell Transplant Center. “The technique has been designed to minimize the inflammatory reaction that is normally observed when islets are implanted in the liver or in other sites with immediate contact to the blood.”
The implanted organ elicits little immune response because some of the components were made out of Peacock’s own biological material. Her blood plasma was mixed with the enzyme thrombin to make a gel-like material to hold donor islet cells. The combination was then placed on Peacock’s omentum and wrapped up to hold it in place and allow integration with the body. Over time, the gel will dissolve and be absorbed into her body, leaving the cells behind to produce insulin. Peacock will need to receive only immunosuppressives that are required for a procedure that introduces donor cells into the body.
“As any type 1 knows, you live on a very structured schedule,” reflected Peacock. “I do a mental checklist every day in my head… glucose tabs, food, glucometer, etc., and then I stop and say, ‘WOW! I don’t have to plan that anymore.’ … I’m still processing the fact that I’m not taking insulin anymore.”
Peacock was selected to receive the transplant because she was suffering from severe hypoglycemia unawareness. With this complication, diabetic patients cannot sense a dangerously low drop in blood glucose levels and become disoriented, lose consciousness, or go into convulsions. If blood glucose becomes too low, death can occur. Completing the clinical trial will be important to allow other type 1 diabetics to receive a DRI BioHub, which may be possible in the coming years.