Développement de surfaces bioactives pour contrôler le comportement cellulaire utilisation de puces de polymères et de biomolécules
Other titre : Development of bioactive surfaces to control cell behavior : use of polymer and biomolecular arrays
Understanding and controlling interactions between cells and material surfaces are essential to design biocompatible and functional medical implants. To this end, bioactive surfaces preventing non-specific biological reactions and providing signals that guide cell behavior are designed. Interactions between surfaces and endothelial cells are particularly important for biomedical applications such as endothelialization of vascular grafts and the development of vascularized artificial tissues by tissue engineering. The aim of this research project is then to develop a bioactive surface specifically interacting with endothelial cells by developing and using arrays of polymers and bioactive surfaces. Arrays of carboxy-methyl-dextran (CMD) are made to determine a low-fouling surface preventing non-specific protein adsorption and cell adhesion. CMD layers are grafted with various conditions and are characterized by X-ray photoelectron spectroscopy (XPS), atomic force microscopy (AFM), exposed to proteins and then fibroblasts, to identify immobilization parameters that influence layers structure and ability to resist non-specific interactions. An optimized surface of CMD is obtained and is as resistant to cell adhesion as a layer of poly(ethylene glycol), the most used low-fouling polymer. Arrays of bioactive surfaces specifically directed toward endothelial cells and made with peptide sequences REDV, SVVYGLR and/or vascular endothelial growth factor (VEGF) are synthesized and exposed to endothelial cells and fibroblasts. Immobilized biomolecules do not promote a selective endothelial adhesion but induce cytoskeleton and focal adhesion reorganization specifically for endothelial cells. Use of polymer arrays allowed the development of a low-fouling surface efficient for the making of bioactive surfaces and biomolecule arrays allowed to study cell responses toward surfaces of various molecular composition.
- Génie – Thèses