Abstract: BACKGROUND ＆ AIM:To explore the possibility of human mesenchymal stem cells (hMSCs) differentiating into neural cells in vivo. MATERIALS AND METHODS: hMSCs labeled with enhanced green fluorescent protein (EGFP) were transplanted into the lateral ventricle of neonatal mouse brain. At 0, 9 and 14 days post-transplantation, mice were sacrificed and their brains were fixed with 4％ paraformaldehyde. The engraftment of transplanted cells in coronal section of the recipient mouse brain was examined under a fluorescent microscope. Indirected immunofluorescent staining was used to detect the expression of neural proteins of these grafted cells. RESULTS: Examination of cryostat section under fluorescent microscopy revealed that hMSCs could engraft into neonatal mouse brain. Neuronal differentiation was confirmed by the expression of β-Ⅲ-Tubulin (Tuj1) and MAP2 of these EGFP-expressing cells, whilst some grafted cells had GFAP staining. CONCLUSION: These results suggest that hMSCs could respond to brain microenvironment and differentiate into neural cells.

Key words: human mesenchymal stem cells, cell transplantation, differentiation, neural cells