title: Combining Yeast Display and Competitive FACS to Select Rare Hapten-Specific Clones from Recombinant Antibody Libraries.
abstract: The development of antibodies to low molecular weight haptens remains challenging due to both the low immunogenicity of many haptens and the cross-reactivity of the protein carriers used to generate the immune response. Recombinant antibodies and novel display technologies have greatly advanced antibody development; however, new techniques are still required to select rare hapten-specific antibodies from large recombinant libraries. In the present study, we used a combination of phage and yeast display to screen an immune antibody library (size, 4.4 × 10(6)) against hapten markers for petroleum contamination (phenanthrene and methylphenanthrenes). Selection via phage display was used first to enrich the library between 20- and 100-fold for clones that bound to phenanthrene-protein conjugates. The enriched libraries were subsequently transferred to a yeast display system and a newly developed competitive FACS procedure was employed to select rare hapten-specific clones. Competitive FACS increased the frequency of hapten-specific scFvs in our yeast-displayed scFvs from 0.025 to 0.005% in the original library to between 13 and 35% in selected pools. The presence of hapten-specific scFvs was confirmed by competitive ELISA using periplasmic protein. Three distinct antibody clones that recognize phenanthrene and methylphenanthrenes were selected, and their distinctive binding properties were characterized. To our knowledge, these are first antibodies that can distinguish between methylated (petrogenic) versus unmethylated (pyrogenic) phenanthrenes; such antibodies will be useful in detecting the sources of environmental contamination. This selection method could be generally adopted in the selection of other hapten-specific recombinant antibodies.
authors: Department of Biochemistry and Molecular Biology, Tulane University School of Medicine , New Orleans, Louisiana, United States.
authors: Yue
authors: Y
authors: Sun
authors: Department of Biochemistry and Molecular Biology, Tulane University School of Medicine , New Orleans, Louisiana, United States.
authors: Bhupal
authors: B
authors: Ban
authors: Bioscience Division, Los Alamos National Laboratory , Los Alamos, New Mexico, United States.
authors: Andrew
authors: A
authors: Bradbury
authors: Department of Pathology, University of Texas Medical Branch , Galveston, Texas, United States.
authors: G A Shakeel
authors: GA
authors: Ansari
authors: Department of Biochemistry and Molecular Biology, Tulane University School of Medicine , New Orleans, Louisiana, United States.
authors: Diane A
authors: DA
authors: Blake
mesh_terms: D000818:Animals; D000911:Antibodies, Monoclonal / Q000276:immunology*; D000915:Antibody Affinity; D000918:Antibody Specificity; D004797:Enzyme-Linked Immunosorbent Assay; D006241:Haptens / Q000276:immunology*; D051379:Mice; D019151:Peptide Library; D010616:Phenanthrenes / Q000276:immunology*; D011994:Recombinant Proteins / Q000276:immunology; D057127:Single-Chain Antibodies / Q000276:immunology*; D020798:Two-Hybrid System Techniques
chemical_list: D000911:Antibodies, Monoclonal; D006241:Haptens; D019151:Peptide Library; D010616:Phenanthrenes; D011994:Recombinant Proteins; D057127:Single-Chain Antibodies; C041507:1-methylphenanthrene