For transient protein expression in mammalian suspension cultures, we currently mainly use HEK293F suspension cells adapted in FreeStyle^TM 293 expression medium. Our standard transfection reagent is PEI MAX, but we’re of course also open to using other transfection reagents when required. We generally perform the high-density transfections of plasmid DNA in TPP TubeSpin® bioreactors. Depending on the volume of the expression cultures, we either grow our cells in sterile Erlenmeyer shake flasks or in 600 ml TPP TubeSpin® bioreactors (working volume ~ 400 ml).

References

Baldi L., Hacker D.L., Adam M., Wurm F.M. (2007) Recombinant protein production by large-scale transient gene expression in mammalian cells: state of the art and future perspectives. Biotechnol Lett. 29(5):677-84. 

Backliwal G., Hildinger M., Kuettel I., Delegrange F., Hacker D.L., Wurm F.M. (2008) Valproic acid: a viable alternative to sodium butyrate for enhancing protein expression in mammalian cell cultures. Biotechnol Bioeng. 101(1):182-9

Hacker D.L., De Jesus M., Wurm F.M. (2009) 25 years of recombinant proteins from reactor-grown cells – where do we go from here? Biotechnol Adv. 27(6):1023-1027

Baldi L., Hacker D.L., Meerschman C. and Wurm F.M. (2012) Large-scale transfection of mammalian cells. Methods Mol Biol. 801:13-26

Kadlecova Z., Nallet S., Hacker D.L., Baldi L., Klok H.A. and Wurm F.M. (2012) Poly(ethyleneimine)-mediated large-scale transient gene expression: influence of molecular weight, polydispersity and N-propionyl groups. Macromol Biosci. 12(5):628-36

Jäger V., Büssow K., Wagner A., Weber S., Hust M., Frenzel A. and Schirrmann T. (2013) High level transient production of recombinant antibodies and antibody fusion proteins in HEK293 cells. BMC Biotechnol. 13:52

Jäger V., Büssow K. and Schirrmann T. (2015) Transient Recombinant Protein Expression in Mammalian Cells. In: Al-Rubeai M. (eds) Animal Cell Culture. Cell Engineering, vol 9. Springer, Cham.