作者单位:Center for Regenerative Medicine, Massachusetts General Hospital, 185 Cambridge Street, Boston, MA[1]Center for Musculoskeletal Research, Johns Hopkins Medicine, 601 North Caroline Street, Baltimore[2]Endocrine Unit, Massachusetts General Hospital, 185 Cambridge Street, Boston, MA 02114, United[3]Advanced Microscopy Program, Wellman Center for Photomedicine and Center for Systems Biology[4]