Production and Concentration of an MLV Based Viral Vector and Comparison of Cancerous and non-Cancerous Cell Lines Transduction with Produced Vector

Various tools have been developed to deliver genes into eukaryotic cells; among them، the efficiency of RNA-containing viruses belonging to the family of Retroviridae is higher than other viruses because integrate their genomes into the target cell chromosomes. The Murine Leukemia Virus (MLV) is the most prominent member of orthoretrovirinae genus of gammaretroviruses. An MLV-based retroviral vector can only express transgenes in cells undergoing mitosis، indicating its suitability as a delivery vehicle for cancer gene therapy. In this study، an MLV-based viral vector was produced in the HEK293T cell line by transient cotransfection of three plasmids including pBABE-GFP (plasmid expressing GFP reporter gene)، pBS–CMV–gagpol (plasmid consisting of Gag-Pol genes) and pMD2. G (plasmid expressing VSVG gene). The produced viral vector was concentrated by ultracentrifuge and poly ethylene glycol methods. Serial dilutions were prepared from concentrated virus and virus titer was calculated according to infectious unit per milliliter (21×106 infectious particles per milliliter in both methods). Then، the transduction efficiency of cancerous cell lines (A549 and Hela) and non- cancerous cell lines (HEK and Vero) was compared by the produced viral vector. The results showed that efficiency of the generated vector to infect cancer cells in comparison with other cells was higher and thus was more suitable for gene transfer into cancer cell lines.