Lentiviral vectors (LV) offer excellent gene delivery vehicles for cell and gene therapy applications. Traditionally, adherent HEK293T cells are transiently transfected with second or third generation vectors to generate LV particles. Although this approach serves the need for preclinical research labs, adherent cells pose inherent difficulties when scaling up to produce GMP grade vectors. While production can be scaled up with adherent HEK293T using multi-stack cell culture flasks, it is not cost effective and operationally inefficient.
To facilitate large scale production of GMP grade LV, we adapted adherent HEK293T cells (ATCC, from SACF) to suspension culture using Thermo Fisher Scientific’s serum free lentiviral production medium. The adapted 293T suspension cells (293TS) produced lentiviral titers comparable or superior to Thermo Fisher’s lentiviral production cells under different conditions. We optimized production conditions that eliminates the requirement of commercial transfection reagents or packaging cocktails to save time and resources.
We validated this cell line for production of LV encoding chimeric antigen receptors (CAR). Currently, we offer high titer RUO grade LV production service using this cell line.