Update on islet transplantation

Abstract

Clinical islet transplantation has progressed considerably over the past 12 years, and >750 patients with type 1 diabetes have received islet transplants internationally over this time. Many countries are beginning to accept the transition from research to accepted and funded clinical care, especially for patients with brittle control that cannot be stabilized by more conventional means. Major challenges remain, including the need for more than one donor, and the requirement for potent, chronic immunosuppression. Combining immunological tolerance both to allo- and autoantigens, and a limitless expandable source of stem cell- or xenograft-derived insulin-secreting cells represent remaining hurdles in moving this effective treatment to a potential cure for all those with type 1 or 2 diabetes.

Figure 1.

Isolated and purified human islets of Langerhans, postculture, ready for transplantation.

Figure 2.

Portal angiogram after percutaneous transhepatic portal access, with catheter tip in the superior mesenteric vein, ready for islet infusion.

Figure 3.

Nine-year insulin independence and C-peptide islet graft function rates with the original Edmonton Protocol immunosuppression. (Data from the University of Alberta.)

Figure 4.

Alternate sites for islet implantation. (Figure from Merani et al. 2008a; reprinted, with permission, from the author.)