Cell transplantation has emerged as a new treatment for myocardial infarction;​ however poor cell survival in the infarct milieu hampers current efforts to maximize therapy. The objective of this dissertation was to better understand the role of limited oxygen and glucose concentrations on survival of transplanted cells in infarcted myocardium. Separating the impact of hypoxia and/or starvation from the impact of inflammatory cells, cytokines, matrix metalloproteases, and other factors present in vivo is daunting. Because of these complexities, there is need for an in vitro model system to directly evaluate the impact of low glucose and hypoxia on cell survival. Unfortunately, simple, two-dimensional cell culture systems are unable to replicate the severe hypoxia/anoxia to which cells are exposed following transplantation into infarct. Therefore, we created and validated a three-dimensional (3-D) culture system where oxygen and nutrients were diffusion-limited, based on construct depth and metabolism by seeded cells. W e first measured oxygen and glucose concentrations in infarcted porcine heart. W e then created a 3-D myoblast culture system, which encompassed those measured values, and quantified cell viability, oxygen and glucose concentrations, and oxygen and glucose consumption rates. The system was then used to quantify myoblast survival under infarct-like conditions and to evaluate techniques designed to improve myoblasts’ viability in the ischemic environment. Oxygen tension, rather than glucose concentration, proved to be the key mediator of cell death in the system. Increasing glucose available to myoblasts was ineffective at decreasing myoblast oxygen consumption rate (expected via Crabtree effect) and/or increasing cell viability;​ however, the use of glutamine-free culture media both reduced myoblast oxygen consumption rates and improved cell viability within the 3-D constructs.

Finally, an in silico computer model was constructed to predict the impact of oxygen and geometry of cell injections on myoblast viability following transplantation into myocardial infarct scar. Injection of myoblasts in long, thin needle tracks proved superior to multiple bolus injections or thin sheet-like injections at maximizing oxygen availability to transplanted cells. The model predicted that multiple needle track injections, used in conjunction with glutamine-free media could improve viability of transplanted cells by up to 80% over current techniques.