Design of a bioartificial pancreas

Abstract

Islet transplantation has been shown to be a viable treatment option for patients afflicted with type 1 diabetes. However, the lack of availablity of human pancreases and the need to use risky immunosuppressive drugs to prevent transplant rejection remain two major obstacles to the routine use of islet transplantation in diabetic patients. Successful development of a bioartificial pancreas using the approach of microencapsulation with perm-selective coating of islets in hydrogels for graft immunoisolation holds tremendous promise for diabetic patients because it has great potential to overcome these two barriers. In this review article, we will discuss the need for a bioartificial pancreas, provide a detailed description of the microencapsulation process, and review the status of the technology in clinical development. We will also critically review the various factors that will need to be taken into consideration in order to achieve the ultimate goal of routine clinical application.

Figure 1

Illustration of islet transplantation (Serup et al., 2001)(with permission).

Figure 2

Illustration of the principle of immunoisolation by microencapsulation

Figure 3

Structure of M and G chains in alginate

Figure 4

Encapsulated islets in an alginate microcapsule. Scale=100 μm.