Pancreas-like extracellular matrix scaffold for successful pancreatic islet transplantation

In clinical islet transplantation, intrahepatically transplanted islets are generally rejected by the host's immune response. However, they are also rapidly destroyed by other mechanisms that are unrelated to immune response. For example, isolated islets can lose the natural pancreatic microenvironment during the islet isolation process, leading to islet cell apoptosis and early graft failure. In a normal pancreas, islets are surrounded by extracellular matrix (ECM) components such as collagen, laminin, fibronectin, and so on. The interactions between islets and these ECM molecules may be very important for islet physiology in the native pancreas. By modulating intracellular signaling pathways, ECM components may play an important role in islet differentiation, proliferation, survival, and insulin secretion. However, the role of ECM molecules in regulation of pancreatic islets is still completely unknown. This article reviews current knowledge of islet-ECM interactions, evaluating the possible use of ECM molecules in improving islet transplantation outcomes. It also discusses several experimental trials of methods for enhancing the viability and functionality of islets