title: 2D-DIGE screening of high-productive CHO cells under glucose limitation--basic changes in the proteome equipment and hints for epigenetic effects.
abstract: CHO derivates (Chinese hamster ovary) belong to the most important mammalian cells for industrial recombinant protein production. Many efforts have been made to improve productivity and stability of CHO cells in bioreactor processes. Here, we followed up one barely understood phenomenon observed with process optimizations: a significantly increased cell-specific productivity in late phases of glucose-limited perfusion cultivations, when glucose (and lactate) reserves are exhausted. Our aim was to elucidate the cellular activities connected to the metabolic shift from glucose surplus to glucose limitation phase. With 2D-DIGE, we compared three stages in a perfusion culture of CHO cells: the initial growth with high glucose concentration and low lactate production, the second phase with glucose going to limitation and high lactate level, and finally the state of glucose limitation and also low lactate concentration but increased cell-specific productivity. With our proteomic approach we were able to demonstrate consequences of glucose limitation for the protein expression machinery which also could play a role for a higher recombinant protein production. Most interestingly, we detected epigenetic effects on the level of proteins involved in histone modification (HDAC1/-2, SET, RBBP7, DDX5). Together with shifts in the protein inventory of energy metabolism, cytoskeleton and protein expression, a picture emerges of basic changes in the cellular equipment under long-term glucose limitation of CHO cells.
authors.affiliation: Institute of Cell Culture Technology, Bielefeld University, Bielefeld, Germany.
authors.forename: Marc
authors.initials: M
authors.lastname: Wingens
authors.affiliation: IBG-1: Biotechnology; Bioprocesses and Bioanalytics, Research Center Jülich, Germany.
authors.forename: Jochem
authors.initials: J
authors.lastname: Gätgens
authors.affiliation: Institute of Cell Culture Technology, Bielefeld University, Bielefeld, Germany.
authors.forename: Anica
authors.initials: A
authors.lastname: Schmidt
authors.affiliation: Bioinformatics Resource Facility, Center for Biotechnology (CeBiTec), Bielefeld University, Bielefeld, Germany.
authors.forename: Stefan P
authors.initials: SP
authors.lastname: Albaum
authors.affiliation: Institute of Cell Culture Technology, Bielefeld University, Bielefeld, Germany.
authors.forename: Heino
authors.initials: H
authors.lastname: Büntemeyer
authors.affiliation: Institute of Cell Culture Technology, Bielefeld University, Bielefeld, Germany.
authors.forename: Thomas
authors.initials: T
authors.lastname: Noll
authors.affiliation: Institute of Cell Culture Technology, Bielefeld University, Bielefeld, Germany. Electronic address: raimund.hoffrogge@uni-bielefeld.de.
authors.forename: Raimund
authors.initials: R
authors.lastname: Hoffrogge
mesh_terms: D000818:Animals; D016466:CHO Cells; D016000:Cluster Analysis; D006224:Cricetinae; D003412:Cricetulus; D044127:Epigenesis, Genetic; D005947:Glucose / Q000378:metabolism*; D020543:Proteome / Q000032:analysis* / Q000737:chemistry / Q000378:metabolism; D040901:Proteomics / Q000379:methods*; D011994:Recombinant Proteins / Q000032:analysis / Q000737:chemistry / Q000378:metabolism; D057825:Two-Dimensional Difference Gel Electrophoresis / Q000379:methods*
chemical_list: D020543:Proteome; D011994:Recombinant Proteins; D005947:Glucose
keywords: Chinese hamster ovary (CHO) cells; Continuous cultivation; Glucose limitation; Histone modification; Metabolic shift; Recombinant protein production