Expression of lentivirus-mediated neurotrophin-3 gene in Schwann cells

ABSTRACT

BACKGROUND:

Neurotrophin-3 is found in the repair of spinal cord injury in the role of the strongest neurotrophic factor.It can effectively promote axonal regeneration through the glial scar tissue in repairing spinal cord injury.

To construct recombinant lentiviral vectors for gene delivery of homo sapiens neurotrophin-3(hNT3),and to investigate the expression of hNT3 gene in Schwann cells after transfection.DESIGN,TIME AND

Observational experiment was performed from June 2007 to March 2008 at the Central Laboratory of Changhai Hospital.MATERIALSBilateral sciatic nerves were harvested from 3-day-old Sprague Dawley rats for culture and identification of Schwann cells.Three-plasmid lentivirus systemspGC-E1-EGFP,pHelper 1.0 and pHelper 2.0 were gained from Shanghai Chemical Technology Co.,Ltd.

pGC-E1-hNT3-EGFP plasmid was constructed by double restriction enzyme digestion and ligation,and then the plasmid was transformed into E.coli DH5?.Purified pGC-E1-hNT3-EGFP plasmids from the positive clones was confirmed by PCR and sequencing.293T cells were cotransfected with lentiviral vector pGC-E1-hNT3-EGFP,pHelper 1.0 and pHelper 2.0 by Lipofectamine 2000 to produce lentivirus.2 mL recombinant virus complete culture solution was added according to multiplicity of infection=1,4,8,10,12.The titer of virus was tested according to the expression level of enhanced green fluorescent protein.The control groups were Schwann cells and Schwann cells transfected by no-loaded lentivirus.MAIN OUTCOME

The lentiviruses were transduced to Schwann cells,and the transfection efficiency was examined by flow cytometry,the overexpression of hNT3 was determined by Real-time PCR and Western blotting.

The exogenous gene sequence of the recombinant hNT3 was completely in accordance with that of its open reading frame in GeneBank.The titer of concentrated virus was 5?107 TU/L.After recombinant LV-hNT3 infection,Schwann cells gave off strikingly bright green fluorescence,and the transfection efficiency amounted to 85%(multiplicity of infection=10).Real-time RCR test showed that the hNT3 mRNA were highly expressed in hNT3-Schwann cells,while did not express in the control group.Western blotting showed the hNT3 expression in Schwann cells.

Construction of hNT3 gene lentiviral vector can transfect Schwann cells leading to an efficient overexpression of hNT3.