1. Department of Histology and Embryology, School of Basic Medical Sciences, Weifang Medical University, Weifang 261053, China
2. Neurologic Disorders and Regenerative Repair Laboratory, Weifang Medical University, Weifang 261053, China
3. Department of Pathology, School of Basic Medical Sciences, Weifang Medical University, Weifang 261053, China
4. Harvard Medical School and Harvard Stem Cell Institute, Harvard University, Boston, MA 02115, USA
5. Department of Neurosurgery, Brigham and Women’s Hospital, Harvard Medical School, Boston, MA 02115, USA