@article{vanHeuvelSchatzHeinetal.2023,
  author    = {Yasemin van Heuvel and Stefanie Schatz and Marc Hein and Tanya Dogra and Daniel Kazenmaier and Natalie Tschorn and Yvonne Genzel and J{\"o}rn Stitz},
  title     = {Novel Suspension Retroviral Packaging Cells Generated by Transposition Using Transposase Encoding mRNA Advance Vector Yields and Enable Production in Bioreactors},
  series   = {Frontiers in Bioengineering and Biotechnology},
  volume    = {11},
  publisher = {Frontiers Media},
  issn      = {2296-4185},
  doi       = {10.3389/fbioe.2023.1076524},
  url       = {https://nbn-resolving.org/urn:nbn:de:hbz:832-epub4-23737},
  year      = {2023},
  abstract  = {To date, the establishment of high-titer stable viral packaging cells (VPCs) at large scale for gene therapeutic applications is very time- and cost-intensive. Here we report the establishment of three human suspension 293-F-derived ecotropic MLV-based VPCs. The classic stable transfection of an EGFP-expressing transfer vector resulted in a polyclonal VPC pool that facilitated cultivation in shake flasks of 100 mL volumes and yielded high functional titers of more than 1 × 106 transducing units/mL (TU/mL). When the transfer vector was flanked by transposon terminal inverted repeats (TIRs) and upon co-transfection of a plasmid encoding for the transposase, productivities could be slightly elevated to more than 3 × 106 TU/mL. In contrast and using mRNA encoding for the transposase, as a proof of concept, productivities were drastically improved by more than ten-fold exceeding 5 × 107 TU/mL. In addition, these VPC pools were generated within only 3 weeks. The production volume was successfully scaled up to 500 mL employing a stirred-tank bioreactor (STR). We anticipate that the stable transposition of transfer vectors employing transposase transcripts will be of utility for the future establishment of high-yield VPCs producing pseudotype vector particles with a broader host tropism on a large scale.},
  language  = {en}
}