Investigation of Cell Mechanotransduction by Nano-optical Biotechnologies

• Main Authors: Chia-Ching Wu, 吳佳慶
• Other Authors: Fong-Chin Su
• Format: Others
• Language: en_US
• Published: 2005
• Online Access: http://ndltd.ncl.edu.tw/handle/69125209925391123714

博士 === 國立成功大學 === 醫學工程研究所碩博士班 === 93 === 　“Tissue Engineers” was been ranked as number 1 out of the ten hottest jobs in 21st century due to the brakethrough in organ failure treatment and the shortage from current options of tissue loss. With integrated interdiscipline of molecular biology, biochemistry, material science, clinical medicine, and biomedical engineering, the tissue engineering has been shown to evolve toward a powerful new paradigm of functional restoration or regeneration of lost or degenerated tissues and organs. While the tissue and cell remodeling is known to involve with the mechanical factors, the way how the cell senses the mechanical force and transduces the signal into gene regulation for remodeling become an important issue for regeneration medicine. 　The advance of the modern micro-electro-mechanical system (MEMS) and nanotechnologies has made the manufacturing scale to be able to be achieved to micrometer (µm, 10-6 meters) and even nanometer (nm, 10-9 meters) which is closely to the cellular or sub-cellular levels. Utilizing Bio-MEMS and nano-optical technologies, we established the manipulation and detection techniques for understanding how the cell senses the mechanical stimulation and transduces the intra- and intercellular signal to restore the tissue function. 　In cell manipulation, we utilized a custom optical tweezers and a self-developed cytodetachment system to quantitatively measure cell adhesion force at each different stage of cell’s life cycle, spreading and migration. We further used microlithography techniques to create different geometrical restriction of cell shape by micropatterning extracellular matrix (ECM) to investigate cell remodeling by application of an external force in different directions. 　For real-time measures of sub-cellular activities, the total internal reflection fluorescent microscopy (TIRFM) and fluorescent resonance energy transfer (FRET) systems were established for investigating the interaction between cell focal adhesion (FAK), phosphorylation of adhesion related molecule (Src), and cytoskeleton remodeling in response to external forces. 　The real-time polymerase chain reaction (PCR) technique was used to monitor the gene regulation during application of the external force, then the mechanism of mechanical sensing, mechanotransduction, and cell remodeling was investigated by protein activities analysis. 　In summary, this thesis described our development and integration of several novel technologies and skills for studies of cellular biomechanics to provide not only the understanding of mechanotransduction, but also broader implication in the regeneration medicine.