Biomaterials and Cells for Revascularization

Cell therapy is often hailed for its potential to revolutionize modern medicine and to treat a wide variety of diseases. The growing enthusiasm surrounding cell-based therapies has resulted in more than 14,560 clinical trials recorded by the NIH over the last decade; however, these trials have not resulted in consistent clinical benefit. These disappointing results could stem from both biological and engineering challenges. While supporting the safety of these cells, these trials have indicated several difficulties hampering clinical/translational potential, including the appropriate cell type, the optimal cell dose, the route of cell administration, the efficiency of cell engraftment at the target tissue, and the frequency of treatment required. Biomaterial systems have been used to bypass some of the limitations arising from cell-based therapies. The biomaterials’ microenvironment protects and increases cell functionality and viability. This chapter will focus on the utility of both naturally occurring and synthetic biomaterial systems to bypass some of the current limitations of cell-based approaches for revascularization therapies. Distinctively, this chapter will cover both the blood and lymphatic vessel systems as critically important targets to resolve vascular problems. The introductory chapter provides an overview of the current clinical outlook that will then be reviewed, followed by a critical evaluation of the current barriers and challenges for clinical success. Then various cell types and sources available for use in vascularization and an overview of different biomaterials currently used for cell transplantation and their applications for revascularization will be examined. Finally, future directions for successful cell-based approaches will be discussed.