title: Antibody light chain variable domains and their biophysically improved versions for human immunotherapy.
abstract: We set out to gain deeper insight into the potential of antibody light chain variable domains (VLs) as immunotherapeutics. To this end, we generated a naïve human VL phage display library and, by using a method previously shown to select for non-aggregating antibody heavy chain variable domains (VHs), we isolated a diversity of VL domains by panning the library against B cell super-antigen protein L. Eight domains representing different germline origins were shown to be non-aggregating at concentrations as high as 450 µM, indicating VL repertoires are a rich source of non-aggregating domains. In addition, the VLs demonstrated high expression yields in E. coli, protein L binding and high reversibility of thermal unfolding. A side-by-side comparison with a set of non-aggregating human VHs revealed that the VLs had similar overall profiles with respect to melting temperature (T(m)), reversibility of thermal unfolding and resistance to gastrointestinal proteases. Successful engineering of a non-canonical disulfide linkage in the core of VLs did not compromise the non-aggregation state or protein L binding properties. Furthermore, the introduced disulfide bond significantly increased their T(m)s, by 5.5-17.5 ° C, and pepsin resistance, although it somewhat reduced expression yields and subtly changed the structure of VLs. Human VLs and engineered versions may make suitable therapeutics due to their desirable biophysical features. The disulfide linkage-engineered VLs may be the preferred therapeutic format because of their higher stability, especially for oral therapy applications that necessitate high resistance to the stomach's acidic pH and pepsin.
authors.affiliation: Human Health Therapeutics; National Research Council Canada; Ottawa, ON Canada.
authors.forename: Dae Young
authors.initials: DY
authors.lastname: Kim
authors.affiliation: Human Health Therapeutics; National Research Council Canada; Ottawa, ON Canada.
authors.forename: Rebecca
authors.initials: R
authors.lastname: To
authors.affiliation: Human Health Therapeutics; National Research Council Canada; Ottawa, ON Canada.
authors.forename: Hiba
authors.initials: H
authors.lastname: Kandalaft
authors.affiliation: Human Health Therapeutics; National Research Council Canada; Ottawa, ON Canada.
authors.forename: Wen
authors.initials: W
authors.lastname: Ding
authors.affiliation: Human Health Therapeutics; National Research Council Canada; Ottawa, ON Canada.
authors.forename: Henk
authors.initials: H
authors.lastname: van Faassen
authors.affiliation: Human Health Therapeutics; National Research Council Canada; Ottawa, ON Canada.
authors.forename: Yan
authors.initials: Y
authors.lastname: Luo
authors.affiliation: Human Health Therapeutics; National Research Council Canada; Montréal, QC Canada.
authors.forename: Joseph D
authors.initials: JD
authors.lastname: Schrag
authors.affiliation: Centre for Vaccine Evaluation; Biologics and Genetic Therapies Directorate;, Health Canada; Ottawa, ON Canada.
authors.forename: Nadereh
authors.initials: N
authors.lastname: St-Amant
authors.affiliation: Centre for Vaccine Evaluation; Biologics and Genetic Therapies Directorate;, Health Canada; Ottawa, ON Canada.
authors.forename: Mary
authors.initials: M
authors.lastname: Hefford
authors.affiliation: Human Health Therapeutics; National Research Council Canada; Ottawa, ON Canada.
authors.forename: Tomoko
authors.initials: T
authors.lastname: Hirama
authors.affiliation: Human Health Therapeutics; National Research Council Canada; Ottawa, ON Canada.
authors.forename: John F
authors.initials: JF
authors.lastname: Kelly
authors.affiliation: Human Health Therapeutics; National Research Council Canada; Ottawa, ON Canada; School of Environmental Sciences; Ontario Agricultural College; University of Guelph; Guelph, ON Canada.
authors.forename: Roger
authors.initials: R
authors.lastname: MacKenzie
authors.affiliation: Human Health Therapeutics; National Research Council Canada; Ottawa, ON Canada; School of Environmental Sciences; Ontario Agricultural College; University of Guelph; Guelph, ON Canada; Department of Biochemistry, Microbiology, and Immunology; University of Ottawa; Ottawa, ON Canada.
authors.forename: Jamshid
authors.initials: J
authors.lastname: Tanha
mesh_terms: D000284:Administration, Oral; D004926:Escherichia coli; D006358:Hot Temperature; D006801:Humans; D006863:Hydrogen-Ion Concentration; D007147:Immunoglobulin Light Chains / Q000737:chemistry* / Q000627:therapeutic use; D055550:Protein Stability; D011994:Recombinant Proteins / Q000737:chemistry; D057127:Single-Chain Antibodies / Q000737:chemistry* / Q000627:therapeutic use
chemical_list: D007147:Immunoglobulin Light Chains; D011994:Recombinant Proteins; D057127:Single-Chain Antibodies
keywords: VL; disulfide linkage; protease resistance; single-domain antibody; thermal stability