U.S. scientists have successfully engineered blood vessels from human vascular cells in the lab, detailing their results in a Research Letter in this week’s issue of The Lancet.
Tissue engineering has made considerable progress in the past decade, but advances have stopped short of clinical application for most tissues. For elderly patients tissue-engineered arteries could provide grafts for bypass surgery. However, generating robust vessels using cells from elderly donors with vascular disease is difficult. One obstacle to generating tissue is the limited life span of adult human cells. Human cells have inbuilt timers called telomeres, which cap the ends of chromosomes, and get shorter every time a cell divides until there is nothing left and the cell stops dividing. Cells isolated from elderly people have shorter telomeres and therefore multiply less than cells from younger people. This is a problem for tissue generation because large numbers of cells must be cultured to produce vessels of clinically relevant size.