Tunable Hydrogels for External Manipulation of Cellular Microenvironmerits through Controlled Photodegradation

摘要

Hydrogels provide a unique environment for three-dimensional cell culture, but typically, the material properties are fixed upon formation. Given the growing interest in understanding how material microenvironments influence cellular functions, numerous approaches have emerged to control not only the initial biochemical and biophysical properties of gels, but also how these properties change with degradation. While these strategies allow the synthesis of hydrogels with predictable degradation profiles and property changes, a material system that allows external manipulation of the properties of a cell-laden gel at any point in time or space would fill a unique niche. For example, such a cell culture system would allow real-time manipulation of the extracellular microenvironment and simultaneous monitoring of cellular processes in three-dimensional culture. In this contribution, photocleavable linkers were integrated into the crosslinks of a poly(ethylene glycol)-based (PEG) hydrogel, allowing the network structure to be tuned exogeneously and predictably with irradiation under cytocompatible conditions. Such a material system will enable new opportunities to test hypotheses about how precise variations in the local gel environment direct important cellular functions, such as process extension, migration, and mechanotransduction.