New protocol for lentiviral vector mass production.

Multiplasmid transient transfection is the most widely used technique for the generation of lentiviral vectors. However, traditional transient transfection protocols using 293 T adherent cells and calcium phosphate/DNA co-precipitation followed by ultracentrifugation are tedious, time-consuming, and difficult to scale up. This chapter describes a streamlined protocol for the fast mass production of lentiviral vectors and their purification by affinity chromatography. Lentiviral particles are generated by transient transfection of suspension growing HEK 293 cells in serum-free medium using polyethylenimine (PEI) as transfection reagent. Lentiviral vector production is carried out in Erlenmeyer flasks agitated on orbital shakers requiring minimum supplementary laboratory equipment. Alternatively, the method can be easily scaled up to generate larger volumes of vector stocks in bioreactors. Heparin affinity chromatography allows for selective concentration and purification of lentiviral particles in a singlestep directly from vector supernatants. The method is suitable for the production and purification of different vector pseudotypes.