In vitro construction of a human blood vessel from cultured vascular cells : a morphologic study

Purpose: The purpose of this study was to create a tubular vascular model exclusively made of human cells and collagen. Methods: The blood vessel equivalent was constructed with the three following human cell types: vascular smooth muscle cells, endothelial cells, and fibroblasts. A tissuelike structure was obtained from the contraction of a tubular collagen gel (human origin) by vascular smooth muscle cells, which created a media-like structure. An adventia- like tissue was added around the media-like structure by embedding fibroblasts into a collagen gel. An endothelium was established within the tubular structure after intraluminal cell seeding. Results: Cell orientation and gel contraction were followed up over time. Vascular smooth muscle cells developed a complex tridimensional network and were oriented in a circular fashion around the tube's axis. In contrast, fibroblasts were randomly oriented. A viable, homogeneous, and well-characterized endothelium was observed. These endothelial cells showed a slightly elongated structure and were oriented parallel to this vascular equivalent axis. Conclusion: An in vitro tridimensional vascular model that exhibits some phenotypic characteristics of in vivo vascular cells could be useful in the study of events that lead to atherosclerotic plaque formations