title: Morphological and histological evaluations of 3D-layered blood vessel constructs prepared by hierarchical cell manipulation.
abstract: Three-dimensional (3D)-layered blood vessel constructs consisting of human umbilical artery smooth muscle cells (SMCs) and human umbilical vascular endothelial cells (ECs) were fabricated by hierarchical cell manipulation, and their basic morphology, histology and blood compatibility  were evaluated in relation to the EC layers. For the hierarchical cell manipulation, fibronectin-gelatin (FN-G) nanofilms were prepared on the surface of SMC layers to provide a cell adhesive nano-scaffold for the second layer of cells. The layer number of blood vessel constructs was easily  controllable from 2 to 7 layers, and the histological evaluation, scanning electron microscope (SEM) and transmission electron microscope (TEM) observations indicated a hierarchical blood vessel analogous morphology. The immunefluorescence staining revealed homogeneous and dense tight-junction  of the uppermost EC layer. Furthermore, the nano-meshwork morphology of the FN-G films like a native extracellular matrix was observed inside the blood vessel constructs by SEM. Moreover, a close association between actin microfilaments and the nano-meshworks was observed on the SMC surface  by TEM. The blood compatibility of the blood vessel constructs, 4-layered SMC/1-layered EC (4L-SMC/1L-EC), was clearly confirmed by inhibition of platelet adhesion, whereas the blood vessel constructs without EC layers (4L-SMC) showed high adhesion and activation of the platelet. The 3D-blood  vessel constructs prepared by hierarchical cell manipulation technique will be valuable as a blood vessel model in the tissue engineering or pharmaceutical fields.
authors.affiliation: Department of Applied Chemistry, Graduate School of Engineering, Osaka University, 2-1 Yamada-oka, Suita, Osaka 565-0871, Japan.
authors.forename: Michiya
authors.initials: M
authors.lastname: Matsusaki
authors.forename: Koji
authors.initials: K
authors.lastname: Kadowaki
authors.forename: Eijiro
authors.initials: E
authors.lastname: Adachi
authors.forename: Takeshi
authors.initials: T
authors.lastname: Sakura
authors.forename: Utako
authors.initials: U
authors.lastname: Yokoyama
authors.forename: Yoshihiro
authors.initials: Y
authors.lastname: Ishikawa
authors.forename: Mitsuru
authors.initials: M
authors.lastname: Akashi
mesh_terms: D001808:Blood Vessels / Q000166:cytology*; D061307:Human Umbilical Vein Endothelial Cells / Q000166:cytology; D006801:Humans; D008422:Materials Testing; D032389:Myocytes, Smooth Muscle / Q000166:cytology; D036103:Nanotechnology / Q000379:methods*; D023822:Tissue Engineering / Q000379:methods*; D014469:Umbilical Arteries / Q000166:cytology