title: Isolation of potent neutralizing monoclonal antibodies from an SIV-Infected rhesus macaque by phage display.
abstract: The humoral immune response is a mechanism that potently suppresses or prevents viral infections. However, genetic diversity and resistance to antibody-mediated neutralization are serious obstacles in controlling HIV-1 infection. In this study, we isolated monoclonal antibodies from an SIV-infected macaque by using the phage display method to characterize antibodies in SIV infection. Variable regions of immunoglobulin genes were amplified by rhesus macaque-specific primers and inserted into the phagemid pComb3X, which produced the Fab fragment. Antibodies against SIV proteins were selected by biopanning using an SIV protein-coated 96-well plate. A total of 20 Fab clones obtained included 14 clones directed to gp41, four clones to gp120, and two clones to p27. The anti-gp120 Fab clones completely neutralized the homologous neutralization-sensitive SIVsmH635FC and the genetically divergent SIVmac316, and showed at least 50% inhibition against the neutralization-resistant strain, SIVsmE543-3. Competition ELISA revealed that these anti-gp120 Fab clones recognize the same epitope on gp120 including the V3 loop. Identification of antibodies with potent neutralizing activity will help to elucidate the mechanisms for inducing broadly neutralizing antibodies.
authors.affiliation: Priority Organization for Innovation and Excellence, Kumamoto University , Honjyo, Japan .
authors.forename: Takeo
authors.initials: T
authors.lastname: Kuwata
authors.forename: Yuko
authors.initials: Y
authors.lastname: Katsumata
authors.forename: Kaori
authors.initials: K
authors.lastname: Takaki
authors.forename: Tomoyuki
authors.initials: T
authors.lastname: Miura
authors.forename: Tatsuhiko
authors.initials: T
authors.lastname: Igarashi
mesh_terms: D000818:Animals; D000911:Antibodies, Monoclonal / Q000276:immunology* / Q000302:isolation & purification; D000914:Antibodies, Viral / Q000276:immunology* / Q000302:isolation & purification; D003429:Cross Reactions; D004797:Enzyme-Linked Immunosorbent Assay; D007140:Immunoglobulin Fab Fragments / Q000235:genetics / Q000276:immunology / Q000302:isolation & purification; D008253:Macaca mulatta; D008969:Molecular Sequence Data; D009500:Neutralization Tests; D019151:Peptide Library; D017422:Sequence Analysis, DNA; D015302:Simian Immunodeficiency Virus / Q000276:immunology*
chemical_list: D000911:Antibodies, Monoclonal; D000914:Antibodies, Viral; D007140:Immunoglobulin Fab Fragments; D019151:Peptide Library