title: Physiological pulsatile flow culture conditions to generate functional endothelium on a sulfated silk fibroin nanofibrous scaffold.
abstract: Many studies have demonstrated that in vitro shear stress conditioning of endothelial cell-seeded small-diameter vascular grafts can improve cell retention and function. However, the laminar flow and pulsatile flow conditions which are commonly used in vascular tissue engineering and hemodynamic studies are quite different from the actual physiological pulsatile flow which is pulsatile in nature with typical pressure and flow waveforms. The actual physiological pulsatile flow leading to temporal and spatial variations of the wall shear stress may result in different phenotypes and functions of ECs. Thus, the aim of this study is to find out the best in vitro dynamic culture conditions to generate functional endothelium on sulfated silk fibroin nanofibrous scaffolds for small-diameter vascular tissue engineering. Rat aortic endothelial cells (RAECs) were seeded on sulfated silk fibroin nanofibrous scaffolds and cultured under three different patterns of flow conditioning, e.g., steady laminar flow (SLF), sinusoidal flow (SF), or physiological pulsatile flow (PPF) representative of a typical femoral distal pulse wave in vivo for up to 24 h. Cell morphology, cytoskeleton alignment, fibronectin assembly, apoptosis, and retention on the scaffolds were investigated and were compared between three different patterns of flow conditioning. The results showed that ECs responded differentially to different exposure time and different flow patterns. The actual PPF conditioning demonstrated excellent EC retention on sulfated silk fibroin scaffolds in comparison with SLF and SF, in addition to the alignment of cells in the direction of fluid flow, the formation of denser and regular F-actin microfilament bundles in the same direction, the assembly of thicker and highly crosslinked fibronectin, and the significant inhibition of cell apoptosis. Therefore, the actual PPF conditioning might contribute importantly to the generation of functional endothelium on a sulfated silk fibroin nanofibrous scaffold and thereby yield a thromboresistant luminal surface.
authors.affiliation: Key Laboratory for Biomechanics and Mechanobiology of Ministry of Education, School of Biological Science and Medical Engineering, Beihang University, Beijing 100191, People's Republic of China.
authors.forename: Xianghui
authors.initials: X
authors.lastname: Gong
authors.affiliation: Key Laboratory for Biomechanics and Mechanobiology of Ministry of Education, School of Biological Science and Medical Engineering, Beihang University, Beijing 100191, People's Republic of China. Electronic address: haifeng.liu@hotmail.com.
authors.forename: Haifeng
authors.initials: H
authors.lastname: Liu
authors.affiliation: Key Laboratory for Biomechanics and Mechanobiology of Ministry of Education, School of Biological Science and Medical Engineering, Beihang University, Beijing 100191, People's Republic of China.
authors.forename: Xili
authors.initials: X
authors.lastname: Ding
authors.affiliation: Key Laboratory for Biomechanics and Mechanobiology of Ministry of Education, School of Biological Science and Medical Engineering, Beihang University, Beijing 100191, People's Republic of China.
authors.forename: Meili
authors.initials: M
authors.lastname: Liu
authors.affiliation: Key Laboratory for Biomechanics and Mechanobiology of Ministry of Education, School of Biological Science and Medical Engineering, Beihang University, Beijing 100191, People's Republic of China.
authors.forename: Xiaoming
authors.initials: X
authors.lastname: Li
authors.affiliation: Key Laboratory for Biomechanics and Mechanobiology of Ministry of Education, School of Biological Science and Medical Engineering, Beihang University, Beijing 100191, People's Republic of China.
authors.forename: Lisha
authors.initials: L
authors.lastname: Zheng
authors.affiliation: Key Laboratory for Biomechanics and Mechanobiology of Ministry of Education, School of Biological Science and Medical Engineering, Beihang University, Beijing 100191, People's Republic of China.
authors.forename: Xiaoling
authors.initials: X
authors.lastname: Jia
authors.affiliation: Key Laboratory for Biomechanics and Mechanobiology of Ministry of Education, School of Biological Science and Medical Engineering, Beihang University, Beijing 100191, People's Republic of China.
authors.forename: Gang
authors.initials: G
authors.lastname: Zhou
authors.affiliation: College of Materials and Engineering, Sichuan University, Chengdu 610065, People's Republic of China.
authors.forename: Yuanwen
authors.initials: Y
authors.lastname: Zou
authors.affiliation: College of Architecture and Environment, Sichuan University, Chengdu 610065, People's Republic of China.
authors.forename: Jinchuan
authors.initials: J
authors.lastname: Li
authors.affiliation: College of Architecture and Environment, Sichuan University, Chengdu 610065, People's Republic of China.
authors.forename: Xuejin
authors.initials: X
authors.lastname: Huang
authors.affiliation: Key Laboratory for Biomechanics and Mechanobiology of Ministry of Education, School of Biological Science and Medical Engineering, Beihang University, Beijing 100191, People's Republic of China. Electronic address: yubofan@buaa.edu.cn.
authors.forename: Yubo
authors.initials: Y
authors.lastname: Fan
mesh_terms: D000818:Animals; D001011:Aorta / Q000166:cytology; D012831:Bombyx / Q000737:chemistry; D002448:Cell Adhesion; D002478:Cells, Cultured; D042783:Endothelial Cells / Q000166:cytology*; D004867:Equipment Design; D005349:Fibroins / Q000737:chemistry*; D057139:Nanofibers / Q000737:chemistry*; D011673:Pulsatile Flow; D051381:Rats; D017207:Rats, Sprague-Dawley; D013314:Stress, Mechanical; D013431:Sulfates / Q000737:chemistry*; D023822:Tissue Engineering / Q000295:instrumentation*; D054457:Tissue Scaffolds / Q000737:chemistry*
chemical_list: D013431:Sulfates; D005349:Fibroins
keywords: Cell retention; Endothelial cells; Functional endothelium; Physiological pulsatile flow; Sulfated silk fibroin