title: E2F-1 overexpression increases viable cell density in batch cultures of Chinese hamster ovary cells.
abstract: The cell density is an inherent constraint in commercial mammalian cell cultures. Here, we describe a cell engineering strategy utilizing the overexpression of the E2F-1 cell cycle transcription factor in CHO DG44 cells that produce a monoclonal antibody in serum-free, suspension culture. Stable pools and cell lines expressing E2F-1 were isolated that attained viable cell densities 20% higher than control cell lines and continued proliferation for an additional day in batch culture. There were no significant changes in antibody production, apoptosis, and cell cycle compared to control cells, nor were the growth effects evident in fed-batch conditions. Overall, E2F-1 overexpression postponed entry into stationary phase in mammalian cells, but perhaps novel E2F-1 variants or combination cell cycle engineering strategies will be necessary to realize significant growth benefits in commercial applications.
authors.affiliation: Department of Chemical and Biomolecular Engineering, The Johns Hopkins University, 3400 North Charles Street, 221 Maryland Hall, Baltimore, MD 21218-2694, USA.
authors.forename: Brian S
authors.initials: BS
authors.lastname: Majors
authors.forename: Nilou
authors.initials: N
authors.lastname: Arden
authors.forename: George A
authors.initials: GA
authors.lastname: Oyler
authors.forename: Gisela G
authors.initials: GG
authors.lastname: Chiang
authors.forename: Nels E
authors.initials: NE
authors.lastname: Pederson
authors.forename: Michael J
authors.initials: MJ
authors.lastname: Betenbaugh
mesh_terms: D000818:Animals; D015153:Blotting, Western; D016466:CHO Cells; D002452:Cell Count; D018929:Cell Culture Techniques; D002470:Cell Survival; D006224:Cricetinae; D003412:Cricetulus; D050687:E2F1 Transcription Factor / Q000378:metabolism*; D015870:Gene Expression; D006801:Humans
chemical_list: D050687:E2F1 Transcription Factor