1 Medical Center, Tsinghua University, Beijing, China
2 Institute of Orthopaedics, General Hospital of People’s Liberation Army, Beijing, China
3 Department of Tissue Engineering, China Medical University, Shenyang, Liaoning, China
4 Department of Orthopedics, Fifth Affiliated Hospital of Xinjiang Medical University, Urumqi, Xinjiang Uygur Autonomous Region, China
This research was supported by the National Natural Science Foundation of China, No. 81360194, and a grant from the National Basic Research Program of China, No. 2014CB542200.