title: Short hairpin RNA targeted to dihydrofolate reductase enhances the immunoglobulin G expression in gene-amplified stable Chinese hamster ovary cells.
abstract: The dihydrofolate reductase (dhfr)/methotrexate (MTX) selection is a common method to conduct gene amplification in stable clones of Chinese hamster ovary (CHO) cells. We previously reported the use of a short hairpin RNA (shRNA) vector targeted to the dhfr gene resulted in improving the intracellular antigen expression in gene-amplified stable CHO cells [Hong, W.W., Wu, S.C., 2007. A novel RNA silencing vector to improve antigen expression and stability in Chinese hamster ovary cells. Vaccine 25 (20), 4103-4111]. Here we investigated the use of the dhfr-targeted shRNA vector for immunoglobulin G (IgG) expression in gene-amplified stable CHO cells. With the use of the dhfr-targeted shRNA vector, the gene-amplified CHO/dhFr(-) cells were found to increase IgG expression at 1.0 microM MTX by more than 100% and to improve the genomic stability of IgG expression in MTX-free cultures by approximately 30%. The use of the dhfr-targeted shRNA vector can enhance the IgG expression in the gene-amplified stable CHO cells and uphold the IgG expression in MTX-free cultures. Utilizing the dhfr-targeted shRNA vector may provide an alternative way to maneuver CHO cell factories for IgG production in cultures.
authors.affiliation: Institute of Biotechnology, Department of Life Science, National Tsing-Hua University, Hsinchu, Taiwan. scwu@life.nthu.edu.tw
authors.forename: Suh-Chin
authors.initials: SC
authors.lastname: Wu
authors.forename: Willy W L
authors.initials: WW
authors.lastname: Hong
authors.forename: Jin-Hwang
authors.initials: JH
authors.lastname: Liu
mesh_terms: D000818:Animals; D016466:CHO Cells; D002999:Clone Cells; D006224:Cricetinae; D003412:Cricetulus; D003470:Culture Media; D005784:Gene Amplification / Q000187:drug effects / Q000235:genetics*; D018628:Gene Dosage; D005786:Gene Expression Regulation; D005822:Genetic Vectors / Q000235:genetics; D007074:Immunoglobulin G / Q000235:genetics*; D008727:Methotrexate / Q000494:pharmacology; D019384:Nucleic Acid Synthesis Inhibitors / Q000494:pharmacology; D034622:RNA Interference; D034741:RNA, Small Interfering / Q000235:genetics*; D013762:Tetrahydrofolate Dehydrogenase / Q000235:genetics*
chemical_list: D003470:Culture Media; D007074:Immunoglobulin G; D019384:Nucleic Acid Synthesis Inhibitors; D034741:RNA, Small Interfering; D013762:Tetrahydrofolate Dehydrogenase; D008727:Methotrexate