title: CHO cell production and sequence improvement in the 13C6FR1 anti-Ebola antibody.
abstract: From March 2014 through February 2015, the Ebola virus spread rapidly in West Africa, resulting in almost 30,000 infections and approximately 10,000 deaths. With no approved therapeutic options available, an experimental antibody cocktail known as ZMapp™ was administered to patients on a limited compassionate-use basis. The supply of ZMapp™ was highly constrained at the time because it was in preclinical development and a novel production system (tobacco plants) was being used for manufacturing. To increase the production of ZMapp™ for an uncertain future demand, a consortium was formed in the fall of 2014 to quickly manufacture these anti-Ebola antibodies in Chinese hamster ovary (CHO) cells using bioreactors for production at a scale appropriate for thousands of doses. As a result of the efforts of this consortium, valuable lessons were learned about the processing of the antibodies in a CHO-based system. One of the ZMapp™ cocktail antibodies, known as c13C6FR1, had been sequence-optimized in the framework region for production in tobacco and engineered as a chimeric antibody. When transfected into CHO cells with the unaltered sequence, 13C6FR1 was difficult to process. This report describes efforts to produce 13C6FR1 and the parental murine hybridoma sequence, 13C6mu, in CHO cells, and provides evidence for the insertion of a highly conserved framework amino acid that improved the physical properties necessary for high-level expression and purification. Furthermore, it describes the technical and logistical lessons learned that may be beneficial in the event of a future Ebola virus or other pandemic viral outbreaks where mAbs are considered potential therapeutics.
authors.affiliation: a Just Biotherapeutics , Seattle , WA USA.
authors.forename: Dean K
authors.initials: DK
authors.lastname: Pettit
authors.affiliation: a Just Biotherapeutics , Seattle , WA USA.
authors.forename: Richard S
authors.initials: RS
authors.lastname: Rogers
authors.affiliation: b Amgen Inc , Thousand Oaks , CA USA.
authors.forename: Kelly
authors.initials: K
authors.lastname: Arthur
authors.affiliation: b Amgen Inc , Thousand Oaks , CA USA.
authors.forename: Yan
authors.initials: Y
authors.lastname: Brodsky
authors.affiliation: a Just Biotherapeutics , Seattle , WA USA.
authors.forename: Rutilio H
authors.initials: RH
authors.lastname: Clark
authors.affiliation: b Amgen Inc , Thousand Oaks , CA USA.
authors.forename: Chris
authors.initials: C
authors.lastname: Crowell
authors.affiliation: c Mapp Biopharmaceutical Inc , San Diego , CA USA.
authors.forename: Jane
authors.initials: J
authors.lastname: Ennis
authors.affiliation: a Just Biotherapeutics , Seattle , WA USA.
authors.forename: Alison
authors.initials: A
authors.lastname: Gillespie
authors.affiliation: a Just Biotherapeutics , Seattle , WA USA.
authors.forename: Ron
authors.initials: R
authors.lastname: Gillespie
authors.affiliation: a Just Biotherapeutics , Seattle , WA USA.
authors.forename: Brittney
authors.initials: B
authors.lastname: Livingston
authors.affiliation: b Amgen Inc , Thousand Oaks , CA USA.
authors.forename: Edith
authors.initials: E
authors.lastname: Nalbandian
authors.affiliation: a Just Biotherapeutics , Seattle , WA USA.
authors.forename: Danielle
authors.initials: D
authors.lastname: Pace
authors.affiliation: a Just Biotherapeutics , Seattle , WA USA.
authors.forename: Pauline
authors.initials: P
authors.lastname: Smidt
authors.affiliation: c Mapp Biopharmaceutical Inc , San Diego , CA USA.
authors.forename: Michael
authors.initials: M
authors.lastname: Pauly
authors.affiliation: a Just Biotherapeutics , Seattle , WA USA.
authors.forename: Ken
authors.initials: K
authors.lastname: Timmons
authors.affiliation: b Amgen Inc , Thousand Oaks , CA USA.
authors.forename: Michael
authors.initials: M
authors.lastname: Trentalange
authors.affiliation: c Mapp Biopharmaceutical Inc , San Diego , CA USA.
authors.forename: Kevin J
authors.initials: KJ
authors.lastname: Whaley
authors.affiliation: c Mapp Biopharmaceutical Inc , San Diego , CA USA.
authors.forename: Larry
authors.initials: L
authors.lastname: Zeitlin
authors.affiliation: a Just Biotherapeutics , Seattle , WA USA.
authors.forename: James N
authors.initials: JN
authors.lastname: Thomas
mesh_terms: D000818:Animals; D058846:Antibodies, Monoclonal, Murine-Derived / Q000096:biosynthesis* / Q000235:genetics; D000914:Antibodies, Viral / Q000096:biosynthesis* / Q000235:genetics; D016466:CHO Cells; D006224:Cricetinae; D003412:Cricetulus; D029043:Ebolavirus; D015870:Gene Expression; D051379:Mice; D011993:Recombinant Fusion Proteins / Q000096:biosynthesis* / Q000235:genetics
chemical_list: D058846:Antibodies, Monoclonal, Murine-Derived; D000914:Antibodies, Viral; D011993:Recombinant Fusion Proteins
keywords: Anti-viral; ebola; manufacturability; thermal stability; ZMapp