Biological and engineering design considerations for vascular tissue engineered blood vessels (TEBVs)

• Initial clinical results with tissue engineered blood vessels are promising.
• Acellular grafts can be rapidly fabricated for applications in high flow.
• Cell-based engineered vessels are needed to reproduce full function of arteries.
• A confluent endothelium still appears to be needed to replace small diameter vessels.
• New approaches to produce vessels should address clinical challenges.

Considerable advances have occurred in the development of tissue-engineered blood vessels (TEBVs) to repair or replace injured blood vessels, or as in vitro systems for drug toxicity testing. Here we summarize approaches to produce TEBVs and review current efforts to (1) identify suitable cell sources for the endothelium and vascular smooth muscle cells, (2) design the scaffold to mimic the arterial mechanical properties and (3) regulate the functional state of the cells of the vessel wall. Initial clinical studies have established the feasibility of this approach and challenges that make TEBVs a viable alternative for vessel replacement are identified.