1Department of Orthopaedics and Traumatology, The Chinese University of Hong Kong, Prince of Wales Hospital, Hong Kong SAR, PR China, E-mail: jguo57@asu.edu
2Lui Che Woo Institute of Innovative Medicine, Faculty of Medicine, The Chinese University of Hong Kong, Hong Kong SAR, China, E-mail: jguo57@asu.edu
3The Chinese University of Hong Kong, Shenzhen Research Institute, Shenzhen, PR China, E-mail: jguo57@asu.edu
4Stem Cells and Regenerative Medicine Laboratory, Li Ka Shing Institute of Health Sciences, The Chinese University of Hong Kong, Hong Kong SAR, China, E-mail: jguo57@asu.edu
5Key Laboratory for Regenerative Medicine, Ministry of Education, School of Biomedical Sciences, The Chinese University of Hong Kong, Hong Kong SAR, PR China, E-mail: jguo57@asu.edu