Hydrogels As Dynamic Niches for Regenerative Medicine

Methods for culturing cells in a biologically relevant context are increasingly needed to study cell and tissue physiology, expand and differentiate stems cells, and to grow replacement tissues for regenerative medicine.  Two-dimensional culture has been the paradigm for in vitro cell culture; however, evidence and intuition suggest that cells behave differently when they are isolated from the complex architecture of their native tissues and constrained to petri dishes.  As a result, researchers are often faced with the need for more physiologically relevant 3D culture environments, and advances in hydrogel materials are providing custom 3D culture microenvironments with highly controlled biochemical and biophysical properties.  Since the native extracellular matrix (ECM) is far from static, ECM hydrogel mimics must also be dynamic in their chemistry to direct complex cellular behavior.  Developing hydrogel mimics of the ECM is an archetypal bioengineering problem, requiring control of numerous properties on multiple time and length scales important in directing critical cellular functions.  New materials systems have the potential to significantly improve our understanding as to how cells receive information from their microenvironment and the role that these dynamic processes may play in applications ranging from controlling the fate of stem cells to growing functional tissue replacements.  This talk will highlight recent advances in hydrogel chemistries for 3D cell culture and methods to control their properties through orthogonal and photochemical reaction mechanisms.