Device design and materials optimization of conformal coating for islets of Langerhans

TLDR

Cell encapsulation with biocompatible, permeable hydrogels could enable transplantation without immunosuppression. We designed and optimized a novel conformal coating approach that yields thin, complete, uniform coatings of similar thickness on islets of varying sizes. The conformal coating preserved glucose‑stimulated insulin release and islet function in culture, reduced transplant volume compared to traditional encapsulation, and, when transplanted into syngeneic diabetic mice, maintained euglycemia for over 100 days without foreign body reaction or impaired revascularization.

Abstract

Significance Cell encapsulation with biocompatible and permeable hydrogels may allow transplantation without immunosuppression. As an alternative to standard microencapsulation approaches that create single-sized capsules around cell clusters of different sizes, we have designed and optimized a novel approach for conformal coating of islets of Langerhans, resulting in thin, complete, and uniform coatings of similar thickness on differently sized islets. Coated islets exhibited no delay in glucose-stimulated insulin release or loss of function during culture, which is often observed with naked islets. The conformal coating reduces transplant volume relative to traditional encapsulation approaches. When transplanted in syngeneic diabetic mice, conformally coated islets restored and maintained euglycemia for more than 100 d with no foreign body reaction and normal revascularization.