Transplantation of islet-like cell clusters derived from human dental pulp stem cells restores normoglycemia in diabetic mice

Background aims. The success of islet transplantation for diabetes depends on the availability of an adequate number of allogeneic or autologous islets. Postnatal stem cells are now considered for the generation of physiologically competent, insulin-producing cells. Our group showed earlier that it is possible to generate functional islets from human dental pulp stem cells by using a serum-free cocktail in a three-step protocol. Methods. We compared the yield of generated islet-like cell clusters (ICCs) from stem cells from pulps of human exfoliated deciduous teeth (SHED) and dental pulp stem cells from permanent teeth (DPSCs). ICCs derived from SHED were packed in immuno-isolatory biocompatible macro-capsules and transplanted into streptozotocin (STZ)-induced diabetic mice. Non-diabetic and diabetic controls were transplanted with macro-capsules with or without islets. Results. SHED were superior to DPSCs. STZ diabetic mice alone and mice transplanted with empty exhibited hyperglycemia throughout the experiment, whereas mice transplanted with macro-capsules containing ICCs were restored to normoglycemia within 3-4 weeks, which persisted for >60 days. Conclusions. Our results demonstrate for the first time that ICCs derived from SHED reverse STZ diabetes in mice without immunosuppression and offer an autologous and non-controversial source of human tissue that could be used for stem cell therapy in diabetes.