1. MRC Centre for Regenerative Medicine, Institute for Stem Cell Research, School of Biological Sciences, The University of Edinburgh, SCRM Building, 5 Little France Drive, Edinburgh, EH16 4UU, UK
2. Wellcome Trust-MRC Stem Cell Institute, University of Cambridge, Tennis Court Road, Cambridge, CB2 1QR, UK
3. Beijing Jing-Meng Stem Cell Technology Co., Ltd, F6, Building B, No. 5-2 Shangdi East Road, Haidian District, Beijing 100085, China