Glucose‐stimulated insulin release: Parallel perifusion studies of free and hydrogel encapsulated human pancreatic islets

• DOI: 10.1002/bit.26442
• Publication Date: 2017-09-02T10:33:57Z
• Authors: Peter Buchwald; Alejandro Tamayo‐...; Vita Manzoli; Alice A. Tomei; Cherie L. Stabler
• Keywords: Pancreatic Islets; Insulin oscillation

To explore the effects immune-isolating encapsulation has on insulin secretion of pancreatic islets and to improve our ability quantitatively describe glucose-stimulated release (GSIR) islets, we conducted dynamic perifusion experiments with isolated human islets. Free (unencapsulated) hydrogel encapsulated were perifused, in parallel, using an automated multi-channel system that allows sample collection high temporal resolution. Results indicated free secrete less per unit mass or islet equivalent (IEQ) than murine a pronounced first-phase peak. While small microcapsules (d = 700 µm) caused only slightly delayed blunted response compared unencapsulated larger capsules 1,800 completely peak decreased total amount released. Experimentally obtained time-profiles fitted complex computational model. This allowed further fine-tuning hormone-release parameters this model, which was implemented COMSOL Multiphysics couple hormone nutrient consumption kinetics diffusive convective transport. The results these GSIR experiments, also supported by modeling, indicate unavoidably lead dampening sustained-release type can slowly respond changes glucose concentration. Bioartificial pancreas devices provide long-term physiologically desirable solutions if immunoisolation biocompatibility considerations are integrated optimized diffusion characteristics design.