title: Optimizing assembly and production of native bispecific antibodies by codon de-optimization.
abstract: When production of bispecific antibodies requires the co-expression and assembly of three or four polypeptide chains, low expression of one chain can significantly limit assembly and yield. κλ bodies, fully human bispecific antibodies with native IgG structure, are composed of a common heavy chain and two different light chains, one kappa and one lambda. No engineering is applied to force pairing of the chains, thus both monospecific and bispecific antibodies are secreted in the supernatant. In this context, stoichiometric expression of the two light chains allows for maximal assembly of the bispecific antibody. In this study, we selected a κλ body with suboptimal characteristics due to low kappa chain expression. Codon optimization to increase expression of the kappa chain did not improve bispecific yield. Surprisingly, progressive introduction of non-optimal codons into the sequence of the lambda chain resulted in lowering its expression for an optimal tuning of the relative distribution of monospecific and bispecific antibodies. This codon de-optimization led to doubling of the κλ body yield. These results indicate that assembly of different proteins into a recombinant complex is an interconnected process and that reducing the expression of one polypeptide can actually increase the overall yield.
authors.affiliation: a Novimmune SA , Plan-les-Ouates , Geneva , Switzerland.
authors.forename: Giovanni
authors.initials: G
authors.lastname: Magistrelli
authors.affiliation: a Novimmune SA , Plan-les-Ouates , Geneva , Switzerland.
authors.forename: Yves
authors.initials: Y
authors.lastname: Poitevin
authors.affiliation: a Novimmune SA , Plan-les-Ouates , Geneva , Switzerland.
authors.forename: Florence
authors.initials: F
authors.lastname: Schlosser
authors.affiliation: a Novimmune SA , Plan-les-Ouates , Geneva , Switzerland.
authors.forename: Guillemette
authors.initials: G
authors.lastname: Pontini
authors.affiliation: a Novimmune SA , Plan-les-Ouates , Geneva , Switzerland.
authors.forename: Pauline
authors.initials: P
authors.lastname: Malinge
authors.affiliation: a Novimmune SA , Plan-les-Ouates , Geneva , Switzerland.
authors.forename: Soheila
authors.initials: S
authors.lastname: Josserand
authors.affiliation: a Novimmune SA , Plan-les-Ouates , Geneva , Switzerland.
authors.forename: Marie
authors.initials: M
authors.lastname: Corbier
authors.affiliation: a Novimmune SA , Plan-les-Ouates , Geneva , Switzerland.
authors.forename: Nicolas
authors.initials: N
authors.lastname: Fischer
mesh_terms: D000818:Animals; D018033:Antibodies, Bispecific / Q000096:biosynthesis*; D003062:Codon; D006801:Humans; D007074:Immunoglobulin G / Q000096:biosynthesis; D007145:Immunoglobulin kappa-Chains / Q000096:biosynthesis / Q000235:genetics; D007146:Immunoglobulin lambda-Chains / Q000096:biosynthesis / Q000235:genetics; D015202:Protein Engineering / Q000379:methods*
chemical_list: D018033:Antibodies, Bispecific; D003062:Codon; D007074:Immunoglobulin G; D007145:Immunoglobulin kappa-Chains; D007146:Immunoglobulin lambda-Chains
keywords: Affinity chromatography; bispecific antibody; co-expression; codon optimization; protein complex assembly; translation