title: Biological insights into the expression of translation initiation factors from recombinant CHOK1SV cell lines and their relationship to enhanced productivity.
abstract: Translation initiation is on the critical pathway for the production of monoclonal antibodies (mAbs) by mammalian cells. Formation of a closed loop structure comprised of mRNA, a number of eukaryotic initiation factors (eIFs) and ribosomal proteins has been proposed to aid re-initiation of translation and therefore increase global translational efficiency. We have determined mRNA and protein levels of the key components of the closed loop, eIFs (eIF3a, eIF3b, eIF3c, eIF3h, eIF3i and eIF4G1), poly(A)-binding protein (PABP) 1 and PABP-interacting protein 1 (PAIP1), across a panel of 30 recombinant mAb-producing GS-CHOK1SV cell lines with a broad range of growth characteristics and production levels of a model recombinant mAb. We have used a multi-level statistical approach to investigate the relationship between key performance indicators (cell growth and recombinant antibody productivity) and the intracellular amounts of target translation initiation factor proteins and the mRNAs encoding them. We show that high-producing cell lines maintain amounts of the translation initiation factors involved in the formation of the closed loop mRNA, maintaining these proteins at appropriate levels to deliver enhanced recombinant protein production. We then utilize knowledge of the amounts of these factors to build predictive models for and use cluster analysis to identify, high-producing cell lines. The present study therefore defines the translation initiation factor amounts that are associated with highly productive recombinant GS-CHOK1SV cell lines that may be targets for screening highly productive cell lines or to engineer new host cell lines with the potential for enhanced recombinant antibody productivity.
authors.affiliation: Centre for Molecular Processing and School of Biosciences, University of Kent, Canterbury, Kent CT2 7NJ, U.K. e.j.hargreaves@kent.ac.uk c.m.smales@kent.ac.uk.
authors.forename: Emma J
authors.initials: EJ
authors.lastname: Mead
authors.affiliation: Centre for Molecular Processing and School of Biosciences, University of Kent, Canterbury, Kent CT2 7NJ, U.K.
authors.forename: Rosalyn J
authors.initials: RJ
authors.lastname: Masterton
authors.affiliation: Lonza Biologics plc, Portway Building, Granta Park, Great Abington, Cambridge CB21 6GS, U.K.
authors.forename: Marc
authors.initials: M
authors.lastname: Feary
authors.affiliation: Lonza Biologics plc, Portway Building, Granta Park, Great Abington, Cambridge CB21 6GS, U.K.
authors.forename: Olga
authors.initials: O
authors.lastname: Obrezanova
authors.affiliation: Pfizer Inc, 1 Burtt Road, Andover, MA 01810, U.S.A.
authors.forename: Lin
authors.initials: L
authors.lastname: Zhang
authors.affiliation: Lonza Biologics plc, Portway Building, Granta Park, Great Abington, Cambridge CB21 6GS, U.K.
authors.forename: Robert
authors.initials: R
authors.lastname: Young
authors.affiliation: Centre for Molecular Processing and School of Biosciences, University of Kent, Canterbury, Kent CT2 7NJ, U.K. e.j.hargreaves@kent.ac.uk c.m.smales@kent.ac.uk.
authors.forename: C Mark
authors.initials: CM
authors.lastname: Smales
mesh_terms: D000818:Animals; D000911:Antibodies, Monoclonal / Q000096:biosynthesis* / Q000235:genetics; D016466:CHO Cells; D060846:Cell Engineering / Q000379:methods*; D006224:Cricetinae; D003412:Cricetulus; D039642:Eukaryotic Initiation Factors / Q000096:biosynthesis* / Q000235:genetics; D015870:Gene Expression; D011994:Recombinant Proteins / Q000096:biosynthesis / Q000235:genetics
chemical_list: D000911:Antibodies, Monoclonal; D039642:Eukaryotic Initiation Factors; D011994:Recombinant Proteins
keywords: Chinese hamster ovary (CHO); messenger ribonucleic acid (mRNA) translation initiation; monoclonal antibody; predictive models; translation factors