title: Two ScFv antibody libraries derived from identical VL-VH framework with different binding site designs display distinct binding profiles.
abstract: In directed evolution experiments, a single randomization scheme of an antibody gene does not provide optimal diversity for recognition of all sizes of antigens. In this study, we have expanded the recognition potential of our universal library, termed ScFvP, with a second distinct diversification scheme. In the second library, termed ScFvM, diversity was designed closer to the center of the antigen binding site in the same antibody framework as earlier. Also, the CDR-H3 loop structures were redesigned to be shorter, 5-12 aa and mostly without the canonical salt bridge between Arg106H and Asp116H to increase the flexibility of the loop and to allow more space in the center of the paratope for binding smaller targets. Antibodies were selected from the two libraries against various antigens separately and as a mixture. The origin and characteristics of the retrieved antibodies indicate that complementary diversity results in complementary functionality widening the spectrum of targets amenable for selection.
authors: Department of Biochemistry and Food Chemistry, University of Turku, 20520 Turku, Finland.
authors: Tuomas
authors: T
authors: Huovinen
authors: Markku
authors: M
authors: Syrjänpää
authors: Hanna
authors: H
authors: Sanmark
authors: Eeva-Christine
authors: EC
authors: Brockmann
authors: Alex
authors: A
authors: Azhayev
authors: Qi
authors: Q
authors: Wang
authors: Markus
authors: M
authors: Vehniäinen
authors: Urpo
authors: U
authors: Lamminmäki
mesh_terms: D000595:Amino Acid Sequence; D001665:Binding Sites; D004076:Digoxigenin / Q000276:immunology; D019020:Directed Molecular Evolution / Q000379:methods*; D006801:Humans; D007147:Immunoglobulin Light Chains / Q000737:chemistry* / Q000235:genetics* / Q000276:immunology; D008387:Marine Toxins; D052998:Microcystins / Q000276:immunology; D008958:Models, Molecular; D008969:Molecular Sequence Data; D017430:Prostate-Specific Antigen / Q000276:immunology; D011487:Protein Conformation; D057127:Single-Chain Antibodies / Q000737:chemistry* / Q000235:genetics* / Q000276:immunology
chemical_list: D007147:Immunoglobulin Light Chains; D008387:Marine Toxins; D052998:Microcystins; D057127:Single-Chain Antibodies; D017430:Prostate-Specific Antigen; C057862:cyanoginosin LR; D004076:Digoxigenin
keywords: CDR-H3; antibody library; phage display; single framework; synthetic diversity