title: Differentiation from embryonic stem cells to vascular wall cells under in vitro pulsatile flow loading.
abstract: This study evaluated the possibility of differentiation from embryonic stem (ES) cells to vascular wall cells by physical (mechanical) stress loading in vitro. A cell mixture containing Flk1-positive cells (ca. 30%) derived from murine ES cells was added to a compliant microporous tube made of segmented polyurethane. The compliance of the tube was close to that of the human artery [the stiffness parameter (beta) = 57.2 (n = 5, SD < 5%)]. The luminal surface of the tube was fully covered with the cells by preincubation for two days in the presence of vascular endothelial growth factor (VEGF). After 2 days of additional incubation without VEGF under static conditions, layering of the grown cells, mostly smooth muscle actin (SMA)-positive cells, was observed only on the luminal surface of the tube. The cells were flat, polygonal, and randomly oriented. On the other hand, after a 2-day incubation under a weak pulsatile flow simulating the human venous systems [wall shear stress (WSS) from -0.98 to 2.2 dyn/cm(2); circumferential strain (CS) 4.6-9.6 x 10(4) dyn/cm(2)] without VEGF, cells in the superficial layer were regularly oriented in the direction of the pulsatile flow. The oriented cells exhibited endothelial-like appearance, indicating that they were platelet endothelial cell adhesion molecule 1 (PECAM1)-positive. In addition, the cells growing into the interstices in the deeper layer showed smooth muscle-like appearance, indicating that they were SMA-positive. Differentiation to two different cell types and segregation of incorporated ES cells may be simultaneously encouraged by the combination of WSS and CS. It is expected that the monobloc building of hierarchically structured hybrid vascular prostheses composed of several vascular wall cell types is possible by physically synchronized differentiation of ES cells.
authors.affiliation: Department of Bioengineering, Advanced Medical Engineering Center, National Cardiovascular Center Research Institute, Suita, Osaka 565-8565, Japan.
authors.forename: Haiying
authors.initials: H
authors.lastname: Huang
authors.forename: Yasuhide
authors.initials: Y
authors.lastname: Nakayama
authors.forename: Kairong
authors.initials: K
authors.lastname: Qin
authors.forename: Kimiko
authors.initials: K
authors.lastname: Yamamoto
authors.forename: Joji
authors.initials: J
authors.lastname: Ando
authors.forename: Jun
authors.initials: J
authors.lastname: Yamashita
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Itoh
authors.forename: Keiichi
authors.initials: K
authors.lastname: Kanda
authors.forename: Hitoshi
authors.initials: H
authors.lastname: Yaku
authors.forename: Yoshihiro
authors.initials: Y
authors.lastname: Okamoto
authors.forename: Yasushi
authors.initials: Y
authors.lastname: Nemoto
mesh_terms: D000199:Actins / Q000378:metabolism; D000818:Animals; D002454:Cell Differentiation; D020099:Coated Materials, Biocompatible; D004622:Embryo, Mammalian / Q000166:cytology*; D004730:Endothelium, Vascular / Q000166:cytology* / Q000378:metabolism / Q000502:physiology; D066298:In Vitro Techniques; D051379:Mice; D019408:Platelet Endothelial Cell Adhesion Molecule-1 / Q000378:metabolism; D011673:Pulsatile Flow; D013234:Stem Cells / Q000166:cytology* / Q000378:metabolism / Q000502:physiology; D013314:Stress, Mechanical; D042461:Vascular Endothelial Growth Factor A / Q000378:metabolism; D040301:Vascular Endothelial Growth Factor Receptor-2 / Q000032:analysis
chemical_list: D000199:Actins; D020099:Coated Materials, Biocompatible; D019408:Platelet Endothelial Cell Adhesion Molecule-1; D042461:Vascular Endothelial Growth Factor A; D040301:Vascular Endothelial Growth Factor Receptor-2