Hydrogels Grafted with Different Oligo-peptide Sequence for Xeno-free Culture of Human Pluripotent Stem Cells

• Main Authors: Yen-Ming Chen, 陳彥名
• Other Authors: Akon Higuchi
• Format: Others
• Language: en_US
• Published: 2016
• Online Access: http://ndltd.ncl.edu.tw/handle/72860705509148966812

碩士 === 國立中央大學 === 化學工程與材料工程學系 === 104 === Human pluripotent stem cells (hPSCs) have significant potential in therapeutic applications for many diseases. The feeder-free cultures using synthetic biomaterials as stem cell culture materials offer more reproducible culture conditions and lower the cost of production without introducing xenogeneic contaminants. Therefore, we investigated hESCs (H9) and human induced pluripotent stem cells (hiPSCs, HPS0077) culture on biomaterials grafted with different sequence of nanosegments. We prepared dishes coated with polyvinylalcohol-co-itaconic acid (PVA-IA) hydrogels having optimal elasticity of 25.3 kPa storage modulus, and grafted with extracellular matrix (ECM)-derived cell-adhesion peptides. hPSCs were cultured in a chemically defined medium on PVA-IA hydrogels grafted with oligopeptide derived from vitronectin (KGGPQVTRGDVFTMP), bone sialoprotein (KGGNGEPRGDTYRAY), heparin binding domain peptide (GKKQRFRHRNRKG), and also two other sequences that are modified from basic oligo-vitronectin, of which we call VN2C (GCGGKGGPQVTRGDVFTMP) and VN2G (GGGGKGGPQVTRGDVFTMP). VN2C contains cysteine (C) amino acid containing sulfur element, which allows that two VN2C peptides form a dimer structure by S-S bonding spontaneously in atmosphere, so this sequence of oligopeptide (VN2C) is expected to have a higher surface density of oligopeptides compared to other oligopeptide. Besides, we also design a branch type oligopeptide structure by using dual activation and grafting methods. Following the reaction of oligopeptide on PVA-IA hydrogels after the first time grafting, another oligopeptide was subsequently grafted to create a branch-like structure. hPSC were expanded on each nanobrush (oligopeptide) grafted hydrogels with different nanobrush design and discussed the optimal design of nanosegments.