My project aims to engineer synthetic microenvironments for the in vitro expansion of satellite cells – the adult stem cell responsible for muscle regeneration. Small numbers of quiescent satellite cells reside in muscle tissue and are activated in response to exercise, injury or disease. Once activated, these cells proliferate, differentiate and fuse to damaged muscle fibers to facilitate repair. Satellite cell-based therapies for diseases such as muscular dystrophy have shown therapeutic potential in small animals; however, several challenges must be resolved before the full potential of satellite cells can be harnessed for medical technologies. One key challenge is expanding satellite cells in culture while maintaining their ability to self-renew. Using 3D synthetic extracellular matrix mimics, I plan to recapitulate biophysical (stiffness) and biochemical (epitopes; spatial patterning of epitopes) aspects of thein vivosatellite cell niche, and test the ability of these engineered microenvironments to support satellite cell expansion. These synthetic culture platforms will not only be useful for generating large pools of regeneration-competent cells for transplant, but will also be useful experimentally for studies of basic satellite cell behaviors.