1. Division of Tissue Engineering, Graduate School of Medicine, The University of Tokyo, Tokyo, Japan.
2. Bone and Cartilage Regenerative Medicine, Graduate School of Medicine, The University of Tokyo, Tokyo, Japan.
3. Department of Cell Biology, Institute of Biomedical Sciences, Nagasaki University, Nagasaki, Japan.
4. Department of Sensory and Motor System Medicine, Graduate School of Medicine, The University of Tokyo, Tokyo, Japan.
5. JR Tokyo General Hospital, Tokyo, Japan.