Development of Perfluorodecalin Contained Microcapsules for Islet Survival and Function

Hypoxic injury of islets is a major obstacle for encapsulated islet transplantation into the peritoneal cavity. To improve oxygen delivery to encapsulated islets, we integrated 20% of the oxygen carrier material, perfluorodecalin (PFD) contained alginate capsules with islets (PFD-alginate). Integration of PFD clearly improved islet viability and decreased reactive oxygen species production compared with islets encapsulated with alginate only (alginate) and naked islets exposed to hypoxia in vitro. In PFD-alginate capsules, HIF-1α expression was minimal, also insulin expression was well secreted. Furthermore, the best islet function represented by glucose-stimulated insulin secretion was observed for the PFD-alginate capsules. In vivo study, the marginal number naked islets and encapsulated islets (alginate and PFD-alginate) were transplanted into streptozotocin-induced diabetic mice. Non-fasting blood glucose levels and intraperitoneal glucose tolerance tests in the PFD-alginate group was lower than in the alginate group. The harvested islets stained positive for insulin in all groups, but the ratio of dead cell area was 4 times higher in the alginate group was than in the PFD-alginate group.

In conclusion, PFD contained alginate microcapsules improved islet function and survival by minimizing the hypoxic damage of islets after intraperitoneal transplantation.