title: Stable microRNA expression enhances therapeutic antibody productivity of Chinese hamster ovary cells.
abstract: MicroRNAs (miRNAs) are short non-coding RNAs that post-transcriptionally regulate the expression of different target genes and, thus, enable engineered gene networks to achieve complex phenotypic changes in mammalian cells. We hypothesized that exploiting this feature of miRNAs could improve therapeutic protein production processes by increasing viable cell densities and/or productivity of the mammalian cells used for manufacturing. To identify miRNAs that increase the productivity of producer cells, we performed a genome wide functional miRNA screen by transient transfection of Chinese hamster ovary (CHO) cells stably expressing an IgG1 antibody (CHO-IgG1). Using this approach, we identified nine human miRNAs that improved the productivities not only of the CHO-IgG1 cells but also of CHO cells expressing recombinant human serum albumin (HSA), demonstrating that the miRNAs act in a product-independent manner. We selected two miRNAs (miR-557 and miR-1287) positively impacting the viable cell density and the specific productivity, respectively, and then stably co-expressed them in IgG1 expressing CHO cells. In these cells, higher IgG1 titers were observed in fed-batch cultures whilst product quality was conserved, demonstrating that miRNA-based cell line engineering provides an attractive approach toward the genetic optimization of CHO producer cells for industrial applications.
authors.affiliation: Institute of Cell Biology and Immunology, University of Stuttgart, Allmandring 31, 70569 Stuttgart, Germany.
authors.forename: Michaela
authors.initials: M
authors.lastname: Strotbek
authors.forename: Lore
authors.initials: L
authors.lastname: Florin
authors.forename: Jennifer
authors.initials: J
authors.lastname: Koenitzer
authors.forename: Anne
authors.initials: A
authors.lastname: Tolstrup
authors.forename: Hitto
authors.initials: H
authors.lastname: Kaufmann
authors.forename: Angelika
authors.initials: A
authors.lastname: Hausser
authors.forename: Monilola A
authors.initials: MA
authors.lastname: Olayioye
mesh_terms: D000818:Animals; D000911:Antibodies, Monoclonal / Q000096:biosynthesis* / Q000235:genetics; D016466:CHO Cells; D006224:Cricetinae; D003412:Cricetulus; D055106:Genome-Wide Association Study; D006801:Humans; D007074:Immunoglobulin G / Q000096:biosynthesis* / Q000235:genetics; D035683:MicroRNAs / Q000096:biosynthesis / Q000235:genetics
chemical_list: D000911:Antibodies, Monoclonal; D007074:Immunoglobulin G; C586026:MIRN1287 microRNA, human; D035683:MicroRNAs
keywords: 6-FAM (6-carboxyfluorescein); CGE; CHO; Cell line engineering; Chinese hamster ovary; FAM; Fed-batch culture; Functional genomic screen; HSA; Homo sapiens-microRNA; Recombinant therapeutic protein production; capillary gel electrophoresis; hsa-miR; human serum albumin; miRNA; miRNA library; microRNA