David J. Mooney, a Professor of Bioengineering at the Harvard School of Engineering and Applied Sciences as well as a core faculty member at the Wyss Institute for Biologically Inspired Engineering at Harvard University, was invited as an honored speaker in the MRS Symposium X meeting. Mooney is a member of both the National Academy of Engineering and the National Academy of Medicine. The Mooney lab focuses on designing biomaterials that affect specific cells functions and making therapies more effective and practical through study of the mechanism of the chemical and mechanical signal that were sensed by cells. His research now focuses on therapeutic angiogenesis, regeneration of musculoskeletal tissues and cancer therapies. In the meeting, he introduced the influence of stress relaxation of hydrogel on cells and demonstrated that faster relaxation of gels promote cell spreading and enhance osteogenesis and new bone formation. Moreover, he put forward that ferrogel with magnetic stimulation can promote new tissue regeneration because active mechanical stimulation share a similar mechanism.