Can myoglobin expression in pancreatic beta cells improve insulin secretion under hypoxia? An exploratory study with transgenic porcine islets.

The feasibility of myoglobin (Mb)-facilitated oxygen transport in improving porcine islet survival under hypoxia was investigated. Discrete groups of islets were transfected with replication-defective adenoviral vector Ad5 respiratory syncitial virus (RSV) to induce expression of Mb or green fluorescent protein (GFP). Native islets served as the controls.

Characterizing short-term release and neovascularization potential of multi-protein growth supplement delivered via alginate hollow fiber devices.

Multi-protein (10-250 kDa) endothelial cell growth supplement (ECGS) contains growth factors of varying sizes resulting in advanced release rates from diffusion-based drug delivery devices. As a result, the biochemical stimulus provided by ECGS for neovascularization in the critical initial stages of cell transplantation in artificial organs may differ from that for single growth factor delivery. In this study, both in vitro and in vivo studies were conducted with ECGS to correlate in vitro release of multiple angiogenic growth factors to vascularization potential in vivo.

Mathematical modeling of myoglobin facilitated transport of oxygen in devices containing myoglobin-expressing cells.

Low pO(2) is perhaps the most significant factor in artificial pancreas failure. In these environments, not only is the beta cell production of insulin reduced, but the cell death rate is also significantly higher. Mathematical models are developed to test the feasibility of facilitated oxygen transport in enhancing O(2) flux to genetically engineered cells in a bioartificial device such as a pancreas.