Angiogenesis in vitro

Abstract
Cloned human and bovine capillary endothelial cells, cultured in tumor-conditioned medium, form capillary tubes. By light microscopy and EM these tubes resemble capillaries in vivo. This 1st demonstration of angiogenesis in vitro shows that all the information necessary to develop an entire capillary network in vitro is expressed by 1 cell type; suggests a mechanism for lumen formation; and offers a possibility of distinguishing between direct and indirect angiogenesis factors.