title: Monoclonal tobacco cell lines with enhanced recombinant protein yields can be generated from heterogeneous cell suspension cultures by flow sorting.
abstract: Plant cell suspension cultures can be used for the production of recombinant pharmaceutical proteins, but their potential is limited by modest production levels that may be unstable over long culture periods, reflecting initial culture heterogeneity and subsequent genetic and epigenetic changes. We used flow sorting to generate highly productive monoclonal cell lines from a heterogeneous population of tobacco BY-2 cells expressing the human antibody M12 by selecting the co-expressed fluorescent marker protein DsRed located on the same T-DNA. Separation yielded ∼35% wells containing single protoplasts and ∼15% wells with monoclonal microcolonies that formed within 2 weeks. Thus, enriching the population of fluorescent cells from initially 24% to 90-96% in the six monoclonal lines resulted in an up to 13-fold increase in M12 production that remained stable for 10-12 months. This is the first straightforward procedure allowing the generation of monoclonal plant cell suspension cultures by flow sorting, greatly increasing the potential of plant cells as an economical platform for the manufacture of recombinant pharmaceutical proteins.
authors: Plant Biotechnology Department, Fraunhofer Institute for Molecular Biology and Applied Ecology, Aachen, Germany.
authors: Janina
authors: J
authors: Kirchhoff
authors: Nicole
authors: N
authors: Raven
authors: Alexander
authors: A
authors: Boes
authors: Jean L
authors: JL
authors: Roberts
authors: Sean
authors: S
authors: Russell
authors: Wiltrud
authors: W
authors: Treffenfeldt
authors: Rainer
authors: R
authors: Fischer
authors: Helga
authors: H
authors: Schinkel
authors: Andreas
authors: A
authors: Schiermeyer
authors: Stefan
authors: S
authors: Schillberg
mesh_terms: D000911:Antibodies, Monoclonal / Q000096:biosynthesis*; D001709:Biotechnology / Q000379:methods; D002460:Cell Line; D002478:Cells, Cultured; D004345:Drug Industry / Q000379:methods; D005434:Flow Cytometry / Q000379:methods*; D006801:Humans; D059828:Plant Cells / Q000378:metabolism*; D030821:Plants, Genetically Modified; D011994:Recombinant Proteins / Q000096:biosynthesis*; D014026:Nicotiana / Q000166:cytology* / Q000378:metabolism*
chemical_list: D000911:Antibodies, Monoclonal; D011994:Recombinant Proteins