title: Use of Flp-mediated cassette exchange in the development of a CHO cell line stably producing erythropoietin.
abstract: The feasibility of the use of Flp-mediated cassette exchange in the development of a CHO cell line, which produces erythropoietin (EPO) stably and largely, was investigated. A stable, high enhanced green fluorescence protein (EGFP)-producing clone was screened by extensive flow cytometric analysis. An EPO expression unit was targeted into the premarked locus of the stable parental clone by Flp-mediated cassette exchange and a correctly targeted clone (FC28T7) was obtained. The EPO production of FC28T7 was proven to be stable in long-term culture. Furthermore, the Flp-mediated cassette exchange did not alter the stable parental clone's characteristics concerning transgene expression level and stability. Taken together, the data obtained here indicated that the establishment of CHO cell lines stably producing a desired protein is achievable using Flp-mediated cassette exchange.
authors.affiliation: Department of Biological Sciences, Korea Advanced Institute of Science and Technology, Daejon, Korea.
authors.forename: Min Soo
authors.initials: MS
authors.lastname: Kim
authors.forename: Gyun Min
authors.initials: GM
authors.lastname: Lee
mesh_terms: D000818:Animals; D016466:CHO Cells; D006224:Cricetinae; D003412:Cricetulus; D004921:Erythropoietin / Q000235:genetics / Q000378:metabolism*; D018628:Gene Dosage; D015870:Gene Expression; D005818:Genetic Engineering; D019426:Integrases / Q000235:genetics / Q000378:metabolism*; D010957:Plasmids / Q000235:genetics; D011994:Recombinant Proteins; D014764:Viral Proteins / Q000235:genetics / Q000378:metabolism*
chemical_list: D011994:Recombinant Proteins; D014764:Viral Proteins; D004921:Erythropoietin; D019426:Integrases