In the quest to develop a lab-grown artificial pancreas, researchers have realized that simply implanting islets (insulin-producing pancreatic cells) into a patient isn’t very effective. The implanted cells tend to die off and the overall benefit of the procedure is negligible.
A team of Israeli scientists has been working to overcome the problem by building a network of blood vessels around the islets to help these cells interact with their new environment. The 3D vessel structure, when implanted into diabetic mice, showed a considerably higher effectiveness over simple islet transplantation. Moreover, and somewhat surprisingly, the researchers report in PLoS ONE that the vessel network “provides key survival signals to pancreatic, hormone-producing cells even in the absence of blood flow.”
From the study abstract:
The tri-culture setup, seeded on highly porous biocompatible polymeric scaffolds closely mimics the natural anatomical context of pancreatic vasculature. Enhanced islet survival correlating with formation of functional tube-like endothelial vessels was demonstrated. Addition of foreskin fibroblasts to islet-endothelial cultures promoted tube-like structure formation, which further supported islet survival as well as insulin secretion. Gene expression profiles of EC growth factors, extracellular matrix (ECM), morphogenes and differentiation markers were significantly different in 2D versus 3D culture systems and were further modified upon addition of fibroblasts. Implantation of prevascularized islets into diabetic mice promoted survival, integration and function of the engrafted engineered tissue, supporting the suggested role of ECs in islet survival. These findings present potential strategies for preparation of transplantable islets with increased survival prospects.
Full open access study in PLoS ONE: Engineered Vascular Beds Provide Key Signals to Pancreatic Hormone-Producing Cells