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HIV-1 gp140 epitope recognition is influenced by immunoglobulin DH gene segment sequence.
- Source :
-
Immunogenetics [Immunogenetics] 2016 Feb; Vol. 68 (2), pp. 145-55. Date of Electronic Publication: 2015 Dec 19. - Publication Year :
- 2016
-
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.
- Subjects :
- Alleles
Amino Acid Motifs
Amino Acid Sequence
Animals
Antibody Formation
B-Lymphocytes immunology
B-Lymphocytes metabolism
Complementarity Determining Regions chemistry
Epitope Mapping methods
Epitopes chemistry
Genotype
Germ Cells metabolism
HIV Envelope Protein gp120 chemistry
HIV Envelope Protein gp120 immunology
HIV Envelope Protein gp41 chemistry
HIV Envelope Protein gp41 immunology
HIV Infections genetics
HIV Infections immunology
HIV Infections virology
Humans
Immunoglobulin Heavy Chains chemistry
Mice
Molecular Sequence Data
Position-Specific Scoring Matrices
Protein Binding immunology
Protein Conformation
Recombinant Proteins chemistry
Recombinant Proteins immunology
Sequence Alignment
env Gene Products, Human Immunodeficiency Virus chemistry
Complementarity Determining Regions genetics
Epitopes immunology
HIV-1 immunology
Immunoglobulin Heavy Chains genetics
env Gene Products, Human Immunodeficiency Virus immunology
Subjects
Details
- Language :
- English
- ISSN :
- 1432-1211
- Volume :
- 68
- Issue :
- 2
- Database :
- MEDLINE
- Journal :
- Immunogenetics
- Publication Type :
- Academic Journal
- Accession number :
- 26687685
- Full Text :
- https://doi.org/10.1007/s00251-015-0890-x