title: HIV-1 gp140 epitope recognition is influenced by immunoglobulin DH gene segment sequence.
abstract: Complementarity Determining Region 3 of the immunoglobulin (Ig) H chain (CDR-H3) lies at the center of the antigen-binding site where it often plays a decisive role in antigen recognition and binding. Amino acids encoded by the diversity (DH) gene segment are the main component of CDR-H3. Each DH has the potential to rearrange into one of six DH reading frames (RFs), each of which exhibits a characteristic amino acid hydrophobicity signature that has been conserved among jawed vertebrates by natural selection. A preference for use of RF1 promotes the incorporation of tyrosine into CDR-H3 while suppressing the inclusion of hydrophobic or charged amino acids. To test the hypothesis that these evolutionary constraints on DH sequence influence epitope recognition, we used mice with a single DH that has been altered to preferentially use RF2 or inverted RF1. B cells in these mice produce a CDR-H3 repertoire that is enriched for valine or arginine in place of tyrosine. We serially immunized this panel of mice with gp140 from HIV-1 JR-FL isolate and then used enzyme-linked immunosorbent assay (ELISA) or peptide microarray to assess antibody binding to key or overlapping HIV-1 envelope epitopes. By ELISA, serum reactivity to key epitopes varied by DH sequence. By microarray, sera with Ig CDR-H3s enriched for arginine bound to linear peptides with a greater range of hydrophobicity but had a lower intensity of binding than sera containing Ig CDR-H3s enriched for tyrosine or valine. We conclude that patterns of epitope recognition and binding can be heavily influenced by DH germ line sequence. This may help explain why antibodies in HIV-infected patients must undergo extensive somatic mutation in order to bind to specific viral epitopes and achieve neutralization.
authors.affiliation: Department of Microbiology, The University of Alabama at Birmingham, Birmingham, AL, 35294, USA.
authors.forename: Yuge
authors.initials: Y
authors.lastname: Wang
authors.affiliation: Department of Biostatistics, The University of Alabama at Birmingham, Birmingham, AL, 35294, USA.
authors.forename: Pratibha
authors.initials: P
authors.lastname: Kapoor
authors.affiliation: Duke Human Vaccine Institute, Duke University School of Medicine, Durham, NC, 27710, USA.
authors.forename: Robert
authors.initials: R
authors.lastname: Parks
authors.affiliation: Department of Microbiology, The University of Alabama at Birmingham, Birmingham, AL, 35294, USA.|Department of Medicine, The University of Alabama at Birmingham, Birmingham, AL, 35294, USA.
authors.forename: Aaron
authors.initials: A
authors.lastname: Silva-Sanchez
authors.affiliation: Duke Human Vaccine Institute, Duke University School of Medicine, Durham, NC, 27710, USA.
authors.forename: S Munir
authors.initials: SM
authors.lastname: Alam
authors.affiliation: Duke Human Vaccine Institute, Duke University School of Medicine, Durham, NC, 27710, USA.
authors.forename: Laurent
authors.initials: L
authors.lastname: Verkoczy
authors.affiliation: Duke Human Vaccine Institute, Duke University School of Medicine, Durham, NC, 27710, USA.
authors.forename: Hua-Xin
authors.initials: HX
authors.lastname: Liao
authors.affiliation: Department of Medicine, The University of Alabama at Birmingham, Birmingham, AL, 35294, USA.
authors.forename: Yingxin
authors.initials: Y
authors.lastname: Zhuang
authors.affiliation: Department of Microbiology, The University of Alabama at Birmingham, Birmingham, AL, 35294, USA.
authors.forename: Peter
authors.initials: P
authors.lastname: Burrows
authors.affiliation: Department of Microbiology, The University of Alabama at Birmingham, Birmingham, AL, 35294, USA.
authors.forename: Michael
authors.initials: M
authors.lastname: Levinson
authors.affiliation: Department of Medicine, The University of Alabama at Birmingham, Birmingham, AL, 35294, USA.
authors.forename: Ada
authors.initials: A
authors.lastname: Elgavish
authors.affiliation: Department of Biostatistics, The University of Alabama at Birmingham, Birmingham, AL, 35294, USA.
authors.forename: Xiangqin
authors.initials: X
authors.lastname: Cui
authors.affiliation: Duke Human Vaccine Institute, Duke University School of Medicine, Durham, NC, 27710, USA.
authors.forename: Barton F
authors.initials: BF
authors.lastname: Haynes
authors.affiliation: Department of Microbiology, The University of Alabama at Birmingham, Birmingham, AL, 35294, USA. hwsj@uab.edu.|Department of Medicine, The University of Alabama at Birmingham, Birmingham, AL, 35294, USA. hwsj@uab.edu.
authors.forename: Harry
authors.initials: H
authors.lastname: Schroeder
mesh_terms: D000483:Alleles; D020816:Amino Acid Motifs; D000595:Amino Acid Sequence; D000818:Animals; D000917:Antibody Formation; D001402:B-Lymphocytes / Q000276:immunology / Q000378:metabolism; D022801:Complementarity Determining Regions / Q000737:chemistry / Q000235:genetics*; D018604:Epitope Mapping / Q000379:methods; D000939:Epitopes / Q000737:chemistry / Q000276:immunology*; D005838:Genotype; D005854:Germ Cells / Q000378:metabolism; D015699:HIV Envelope Protein gp120 / Q000737:chemistry / Q000276:immunology; D015700:HIV Envelope Protein gp41 / Q000737:chemistry / Q000276:immunology; D015658:HIV Infections / Q000235:genetics / Q000276:immunology / Q000821:virology; D015497:HIV-1 / Q000276:immunology*; D006801:Humans; D007143:Immunoglobulin Heavy Chains / Q000737:chemistry / Q000235:genetics*; D051379:Mice; D008969:Molecular Sequence Data; D056510:Position-Specific Scoring Matrices; D011485:Protein Binding / Q000276:immunology; D011487:Protein Conformation; D011994:Recombinant Proteins / Q000737:chemistry / Q000276:immunology; D016415:Sequence Alignment; D054299:env Gene Products, Human Immunodeficiency Virus / Q000737:chemistry / Q000276:immunology*
chemical_list: D022801:Complementarity Determining Regions; D000939:Epitopes; D015699:HIV Envelope Protein gp120; D015700:HIV Envelope Protein gp41; D007143:Immunoglobulin Heavy Chains; D011994:Recombinant Proteins; D054299:env Gene Products, Human Immunodeficiency Virus; C097729:gp140 envelope protein, Human immunodeficiency virus 1
keywords: Complementarity determining region (CDR-H3); Epitope; HIV-1 envelope protein; Immunoglobulin DH gene