Effect of an oxygen-generating scaffold on the viability and insulin secretion function of porcine neonatal pancreatic cell clusters.

Background: Islet encapsulation techniques have shown limited success in maintaining islet survival and function because encapsulation decreases oxygen supply. In this study, an oxygen-generating scaffold was fabricated to prevent hypoxic cell damage and improve the viability and insulin secretion of islets.

Methods: We fabricated an oxygen-generating scaffold by mixing calcium peroxide (CaO ) with polydimethylsiloxane (PDMS). We evaluated the effects of the oxygen-generating PDMS + CaO scaffold on viability, caspase-3 and caspase-7 activity, oxygen consumption rate (OCR), glucose-stimulated insulin secretion (GSIS), hypoxic cell marker expression, and reactive oxygen species (ROS) levels in porcine neonatal pancreatic cell clusters (NPCCs). We also fabricated a microfluidic device that allowed measuring the effects of the oxygen-generating scaffold on viability.

Results: Oxygen generation by the PDMS + CaO scaffold was sustained for more than 24 hours in vitro. NPCCs encapsulated in PDMS + CaO showed higher viability than NPCCs in PDMS scaffolds and control NPCCs grown without a scaffold. PDMS + CaO -encapsulated NPCCs showed lower caspase-3 and caspase-7 activity, hypoxic cell expression, and ROS levels, and higher OCR and GSIS than those in PDMS or control cells. Using the microfluidic device, we observed that the viability of PDMS + CaO -encapsulated NPCCs was higher than that of PDMS-encapsulated NPCCs.

Conclusions: NPCCs in PDMS + CaO scaffolds show higher viability and insulin secretion than do NPCCs in PDMS scaffolds and control cells. Therefore, this oxygen-generating scaffold has potential for application in future islet transplantation studies.