Functional small-diameter neovessels created using endothelial progenitor cells expanded ex vivo

View article at: http://www.nature.com/nm/journal/v7/n9/pdf/nm0901-1035.pdf
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The objective of this research is to create small diameter blood vesselswith endothelial progenitor cells (EPCs) that circulate in the blood. EPCs from peripheral blood are an endothelial cell source and typicallymigrate to regions with injured endothelia. What makes EPCs unique is itsability to produce nitric oxide, a vasodilator, and promote patency. Previously, in vitro culture of smooth muscles and endothelial cells onbiodegradable or biological scaffold material were used to produce avessel, but these grafts often times developed thrombosis, aggregation of blood factors that causes vascular obstruction, shortly after implantation.

EPCs were first isolated from blood samples from 1 to 2 week old lambs,cultured ex vivo, and then seeded onto decellularized vascular vesselsprepared from porcine iliac arteries 4 mm in diameter and 4-5 cm inlength. After seeding, grafts were preconditioned with variations ofshear stress in order to achieve maximal retention. The production ofnitric oxide was then assessed using an organ chamber. When exposed tocalcium inonphore A23187, grafts not seeded with EPCs remained contractedwhile grafts seeded with EPCs relaxed. This shows that EPC-seeded graftsproduced nitric oxide. EPC-seeded grafts were then implanted into sheepand data shows that all grafts seeded with EPCs were fully patent 130 daysafter implantation, whereas non-seeded EPC grafts occluded within 15 days. Due to the EPC-seeded grafts’ ability to contract and produce nitricoxide proves that EPCs are ideal in creating small-diameter vessels.

I chose this article because it is relevant and applicable to a large majority of the population since cardiovascular disease continues to be the leading cause of death in the US. It's also valuable to know that studies are being done to provide alternative, non-invasive treatments for cardiovascular disease.