the effects of microfluidic shear stress on endothelial differentiation of amniotic fluid stem cells

• Main Authors: Po-Chun Tsai, 蔡伯駿
• Other Authors: Long-Sun Huang
• Format: Others
• Language: zh-TW
• Published: 2010
• Online Access: http://ndltd.ncl.edu.tw/handle/14799115032060621809

碩士 === 臺灣大學 === 應用力學研究所 === 98 === Stem cell therapies for cardiovascular diseases are of great growing interest. Micro-electro-mechanism-system (MEMS) fabricated chips provide more in vivo like cell-to-cell distance and culturing volume than that in centimetre-scaled experiments. In this thesis, we are able to accelerate the process of endothelial differentiation of human amniotic fluid stem cells (hAFSCs) by the stimulation of fluidic shear stress in a MEMS-fabricated micro device. Cells aligning to flow directions is a known property of endothelial cells. hAFSCs affected by 12 dyne/cm2 of shear stress were compiled statistics for the arrangement angles toward the flow direction in a 24-hour period. The angular distribution of cells after 3 hours of stress stimulation approaches to that of cells after 24 hours, indicating similar degrees of endothelial differentiation. Both cell samples stimulated by 12 dyne/cm2 stress after 3 hours and 24 hours exhibit protein expressions of platelet endothelial cell adhesion molecule (PECAM-1) and von Willebrand Factor (vWF). Over ten folds of gene expressions in PECAM-1, vWF and vascular endothelial growth factor-2 receptor (VEGFR) appeared after 3 hours stimulation. Uptakes of ac-LDL and formation of tube-like structure on Matrigel were also observed after shear stress stimulation. Cells stimulated by 12dyne/cm2 shear stress have higher degrees of differentiation than those stimulated by 3, 6, and 18 dyne/cm2 shear stress. Utilizing 3 hours to achieve differentiation instead of days in macro-scale experiments, this micro fluidic system has been proved successful for a rapid shear stress stimulation of hAFSCs differentiation into endothelial cells. This research shows its great potential in stem cell therapy and cardiovascular disease studies.