RÉSUMÉ
BACKGROUND:Nerve growth factor (NGF) belongs to a biological macromolecule that is difficult to pass through the blood-brain barrier. However, a retroviral vector carrying exogenous gene can be stably inserted and integrated into the host cellgenome, which is suitable for gene therapy. OBJECTIVE:To study the gene expression of recombinant retroviral vector carrying rat NGF gene in neural stem cels. METHODS: The rat NGF gene was inserted into a retroviral vector pLEGFP-N1, which was transferred into packaging cels PT67 by Lipofectamine 2000. The positive clones in virus supernatant were colected by G418 selection and used to infect neural stem cels. After that, the NGF expression was tested by enzyme linked immunosorbent assay and the biological competence by PC12 cels, and then morphological change of neural stem cels and celltyping were examined by fluorescent microscope. RESULTS AND CONCLUSION:The neural stem cels could express extrinsic source NGF protein after the recombinant plasmid was infected into neural stem cels. The PC12 cels increased in the experimental group and stretched out long neurites. And the NGF protein could maintain the neural stem cellsurvival and stimulate their differentiation. These findings suggest that the neural stem cels carrying extrinsic source NGF gene could express NGF successfuly, and the NGF protein induced the survival and differentiation of neural stem cels.