It is hypothesized in this research that 1) by mimicking facilitated oxygen transport in avascular tissues, the immunoprotected islets release a higher amount of insulin, recover their intrinsic biphasic release pattern, and prolong their life-span, and 2) insulinotropic agents further promote insulin secretion from islets. Based on these hypotheses, a new BAP system will be designed which contains the water-soluble polymeric conjugates of oxygen carriers (or oxygen binding vehicles) and islet stimulants of sulfonylurea compounds and glucagon-like insulinotropic peptide-1 with entrapped islets in the BAP. The research examines their effects on islet viability, the amount of insulin secretion, the insulin release profile, and the life-span of immunoprotected pancreatic islets. Especially, the combined synergy effects of both hypotheses will be emphasized.

The successful results in improving functionality and life- span of islets entrapped in an immunoprotected membrane can be applied in the delivery of microencapsulated therapeutic cells and to the miniaturization of a BAP. In addition, the approaches proposed in this research will provide a potential solution to the shortage problem of human cell or tissue sources.