title: Improving the secretory capacity of Chinese hamster ovary cells by ectopic expression of effector genes: Lessons learned and future directions.
abstract: Chinese hamster ovary (CHO) cells are the preferred cell factory for the production of therapeutic glycoproteins. Although efforts primarily within bioprocess optimization have led to increased product titers of recombinant proteins (r-proteins) expressed in CHO cells, post-transcriptional bottlenecks in the biosynthetic pathway of r-proteins remain to be solved. To this end, the ectopic expression of transgenes (effector genes) offers great engineering potential. However, studies on effector genes have in some cases led to inconsistent results. Whereas this can in part be attributed to product specificity, other experimental and cellular factors are likely important contributors to these conflicting results. Here, these factors are reviewed and discussed with the objective of guiding future studies on effector genes.
authors.affiliation: The Novo Nordisk Foundation Center for Biosustainability, Technical University of Denmark, Kgs. Lyngby, Denmark. Electronic address: hgra@biosustain.dtu.dk.
authors.forename: Henning Gram
authors.initials: HG
authors.lastname: Hansen
authors.affiliation: The Novo Nordisk Foundation Center for Biosustainability, Technical University of Denmark, Kgs. Lyngby, Denmark.
authors.forename: Nuša
authors.initials: N
authors.lastname: Pristovšek
authors.affiliation: The Novo Nordisk Foundation Center for Biosustainability, Technical University of Denmark, Kgs. Lyngby, Denmark.
authors.forename: Helene Faustrup
authors.initials: HF
authors.lastname: Kildegaard
authors.affiliation: The Novo Nordisk Foundation Center for Biosustainability, Technical University of Denmark, Kgs. Lyngby, Denmark; Department of Biological Sciences, KAIST, 291 Daehak-ro, Yuseong-gu, Daejeon 305-701, Republic of Korea. Electronic address: gyunminlee@kaist.ac.kr.
authors.forename: Gyun Min
authors.initials: GM
authors.lastname: Lee
mesh_terms: D000818:Animals; D016466:CHO Cells / Q000378:metabolism; D060846:Cell Engineering / Q000379:methods*; D006224:Cricetinae; D003412:Cricetulus; D000066630:Ectopic Gene Expression / Q000235:genetics*; D004721:Endoplasmic Reticulum / Q000235:genetics / Q000378:metabolism; D018628:Gene Dosage / Q000235:genetics; D011994:Recombinant Proteins / Q000235:genetics / Q000378:metabolism
chemical_list: D011994:Recombinant Proteins
keywords: Cell engineering; Chinese hamster ovary (CHO) cells; ER stress; Ectopic expression; Endoplasmic reticulum; Gene dosage; Product quality; Recombinant protein production; Secretion bottleneck; Specific productivity