title: Generation of a cholesterol-independent, non-GS NS0 cell line through chemical treatment and application for high titer antibody production.
abstract: NS0 cells require exogenous cholesterol for growth. The non-glutamine synthetase (GS) cholesterol-dependent NS0 host was treated with 5-azacytidine (5azaC), a demethylation drug, and adapted to grow in cholesterol-free, chemically defined medium. Within 7 weeks, a stable, cholesterol-independent NS0 host (NS0.CF) was obtained. The new NS0.CF host, as well as the original cholesterol auxotroph host, was transfected with the same mAb expression plasmid, and the top producing clone from both hosts were compared side-by-side in the enhanced platform fed-batch cultures using chemically defined media. The NS0.CF derived clone significantly out-performed the cholesterol-dependent clone, with titer reaching 4.5 g/L versus 3.0 g/L, respectively, mainly due to higher specific productivity, while key product quality attributes remained comparable. This work demonstrated an effective and rapid approach to generate a cholesterol-independent NS0 host, and its application in recombinant protein production.
authors.affiliation: Oceanside Pharma Technical Development, Genentech, Inc, Oceanside, California, USA.
authors.forename: Jincai
authors.initials: J
authors.lastname: Li
authors.forename: Wei
authors.initials: W
authors.lastname: Gu
authors.forename: Diane G
authors.initials: DG
authors.lastname: Edmondson
authors.forename: Connie
authors.initials: C
authors.lastname: Lu
authors.forename: Natarajan
authors.initials: N
authors.lastname: Vijayasankaran
authors.forename: Bruno
authors.initials: B
authors.lastname: Figueroa
authors.forename: Dave
authors.initials: D
authors.lastname: Stevenson
authors.forename: Thomas
authors.initials: T
authors.lastname: Ryll
authors.forename: Feng
authors.initials: F
authors.lastname: Li
mesh_terms: D000818:Animals; D000911:Antibodies, Monoclonal / Q000235:genetics; D000917:Antibody Formation; D001374:Azacitidine / Q000494:pharmacology; D061249:Batch Cell Culture Techniques / Q000379:methods*; D001709:Biotechnology / Q000379:methods*; D016466:CHO Cells; D002460:Cell Line; D002784:Cholesterol / Q000378:metabolism; D002999:Clone Cells; D006224:Cricetinae; D004791:Enzyme Inhibitors / Q000494:pharmacology; D005974:Glutamate-Ammonia Ligase / Q000378:metabolism; D010957:Plasmids / Q000235:genetics; D011994:Recombinant Proteins / Q000235:genetics; D014162:Transfection
chemical_list: D000911:Antibodies, Monoclonal; D004791:Enzyme Inhibitors; D011994:Recombinant Proteins; D002784:Cholesterol; D005974:Glutamate-Ammonia Ligase; D001374:Azacitidine