1. Department of Orthopedics, Tongji Hospital Affiliated to Tongji University, School of Medicine, Tongji University, Shanghai 200331, China
2. Key Laboratory of Spine and Spinal Cord Injury Repair and Regeneration of Ministry of Education, School of Life Science and Technology, Tongji University, Shanghai 200065, China
3. Frontier Science Center for Stem Cell Research, Tongji University, Shanghai 200065, China