Blood vessel, tissue engineering with

A chitosan-based tubular scaffold with a sandwich-like structure for blood vessel tissue engineering... 

The development of a functional TEVG is likely to require the constmction of an intima and media composed of endothelial and smooth muscle cells. Limitations imposed by immunogenicity will probably require that autologous cells be used, so the majority of studies to date have used differentiated smooth muscle and endothelial cells isolated from harvested blood vessels. But problems with donor-site morbidity and the performance of these cell types in engineered tissues have led to the consideration of alternative cell sources. Recent advances in stem cell biology may lead to suitable progenitors that can be effectively differentiated into endothelial and smooth muscle cells for use in vascular tissue engineering. 

Most of the commonly used degradable polymer scaffolds are mechanically strong, but for certain applications such as engineering muscles and tendons, which require considerable elasticity, these polymers are not optimal. Novel biodegradable polyesters have been developed with superior elasticity and strength that resemble vulcanized rubber and are hence termed as biorubber. Scaffolds made with these mechanically functional materials may be useful especially in engineering elastic tissue such as muscular-skeletal tissues and blood vessels. 

Niklason and Langer studied the feasibility of using PLGA and PGA for tissue-engineered, small diameter blood vessels. They reported that PLGA films supported confluent monolayers of aortic smooth muscle and endothelial cells, and PGA mesh scaffolds developed a tissue-like appearance when seeded with aortic smooth muscle cells. They also claimed that PGA scaffolds formed into a tube did not maintain sufficient strength required for blood vessels, even with smooth muscle tissue formed on the polymer. In an effort to improve the results, they applied pulsatile stretch forces to the cell-polymer... 

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