Current Status on Immunoprotection of Transplanted Islets: Focus on Islet Microencapsulation

This minireview focuses on recent developments in the field of islet microencapsulation as one of the strategies for immunoprotection of transplanted insulin-producing cells for future diabetes treatment. A growing number of peerreviewed publications and reviews in the last few years demonstrate both the progress and strong motivation to identify safe and functional biomaterials. This minireview is primarily based on a literature survey covering the last few years, with the main section devoted to the discussion of various microcapsule types currently under development. The information on microcapsules is complemented by a brief discussion of two additional current strategies used for immunoprotection, namely macroencapsulation and conformal coating, to capture the overall situation in the field of islet encapsulation and transplantation. This is followed by briefly commenting on the characterization of encapsulation devices. In conclusion, the past and very recent achievements (1) reveal that islet microencapsulation remains a vital strategy to protect islet cells and (2) allow for proposing the next steps to bring this strategy closer to clinics.