Skip to main content

High performance CHO cell line development platform for enhanced production of recombinant proteins including difficult-to-express proteins


In an effort to improve product yield of mammalian cell lines, we have previously demonstrated that our proprietary DNA elements, Selexis Genetic Elements (SGEs), increase the transcription of a given transgene, thus boosting the overall expression of a therapeutic protein drug in mammalian cells [1]. However, there are additional cellular bottlenecks, notably in the molecular machineries of the secretory pathways. Most importantly, mammalian cells have some limitations in their intrinsic capacity to manage high level of protein synthesis as well as folding recombinant proteins. These bottlenecks often lead to increased cellular stress and, therefore, low production rates.

Material and Methods

Our specific approach involves CHO cell line engineering. We constructed CHO-M libraries based upon the CHO-M genome and transcriptome and using unique proprietary transposon vectors harboring SGE DNA elements to compensate for rate-limiting factors [2]. Each CHO-Mplus library displays a diversity of auxiliary proteins involved in secretory pathway machineries and cellular metabolism. Collectively, the libraries address a broad range of expression issues.


Figure 1 shows that our CHO-Mplus libraries enabled the selection of a clonal cell line expressing 12 fold more product by comparison to the unmodified host cell [3].

Figure 1

The iterative application of the CHO-Mplus libraries enabled >10 fold increase in productivity of ScFv:Fc without changes in gene copy number or transcription level of gene of interest.


Our results demonstrate that components of the secretory and processing pathways can be limiting, and that engineering of the metabolic pathway ('omic' profiling) improves the secretion efficiency of therapeutic proteins from CHO cells.


  1. 1.

    Girod PA, Nguyen DQ, Calabrese D, Puttini S, Grandjean M, Martinet D, Regamey A, Saugy D, Beckmann JS, Bucher P, Mermod N: Genome-wide prediction of matrix attachment regions that increase gene expression in mammalian cells. Nature Methods. 2007, 4: 747-753. Epub 2007 Aug 5

    Article  CAS  PubMed  Google Scholar 

  2. 2.

    Ley D, Harraghy N, Le Fourn V, Bire S, Girod PA, Regamey A, Rouleux-Bonnin F, Bigot Y, Mermod N: MAR Elements and Transposons for Improved Transgene Integration and Expression. PLoS One. 2013, 8: e62784-

    PubMed Central  Article  CAS  PubMed  Google Scholar 

  3. 3.

    Le Fourn V, Girod PA, Buceta M, Regamey A, Mermod N: CHO cell engineering to prevent polypeptide aggregation and improve therapeutic protein secretion. Metab Eng. 2013, Feb 1. pii: S1096-7176(13)00002-5. doi: 10.1016/j.ymben.2012.12.003. [Epub ahead of print], []

    Google Scholar 

Download references

Author information



Corresponding author

Correspondence to Pierre-Alain Girod.

Rights and permissions

This article is published under license to BioMed Central Ltd. This is an Open Access article distributed under the terms of the Creative Commons Attribution License (, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. The Creative Commons Public Domain Dedication waiver ( applies to the data made available in this article, unless otherwise stated.

Reprints and Permissions

About this article

Cite this article

Girod, P., Le Fourn, V., Calabrese, D. et al. High performance CHO cell line development platform for enhanced production of recombinant proteins including difficult-to-express proteins. BMC Proc 7, P75 (2013).

Download citation


  • Secretory Pathway
  • Therapeutic Protein
  • Mammalian Cell Line
  • Protein Drug
  • Clonal Cell Line