title: CD8 epitope escape and reversion in acute HCV infection.
abstract: In the setting of acute hepatitis C virus (HCV) infection, robust HCV-specific CD8+ cytotoxic T lymphocyte (CTL) responses are associated with initial control of viremia. Despite these responses, 70-80% of individuals develop persistent infection. Although viral escape from CD8 responses has been illustrated in the chimpanzee model of HCV infection, the effect of CD8 selection pressure on viral evolution and containment in acute HCV infection in humans remains unclear. Here, we examined viral evolution in an immunodominant human histocompatibility leukocyte antigen (HLA)-B8-restricted NS3 epitope in subjects with acute HCV infection. Development of mutations within the epitope coincided with loss of strong ex vivo tetramer and interferon gamma enzyme-linked immunospot responses, and endogenous expression of variant NS3 sequences suggested that the selected mutations altered processing and presentation of the variant epitope. Analysis of NS3 sequences from 30 additional chronic HCV-infected subjects revealed a strong association between sequence variation within this region and expression of HLA-B8, supporting reproducible allele-specific selection pressures at the population level. Interestingly, transmission of an HLA-B8-associated escape mutation to an HLA-B8 negative subject resulted in rapid reversion of the mutation. Together, these data indicate that viral escape from CD8+ T cell responses occurs during human HCV infection and that acute immune selection pressure is of sufficient magnitude to influence HCV evolution.
authors.affiliation: Partners AIDS Research Center, Massachusetts General Hospital, Harvard Medical School, Bldg. 149, 13th St., Rm. 6618 B, Boston, MA 02114, USA.
authors.forename: Joerg
authors.initials: J
authors.lastname: Timm
authors.forename: Georg M
authors.initials: GM
authors.lastname: Lauer
authors.forename: Daniel G
authors.initials: DG
authors.lastname: Kavanagh
authors.forename: Isabelle
authors.initials: I
authors.lastname: Sheridan
authors.forename: Arthur Y
authors.initials: AY
authors.lastname: Kim
authors.forename: Michaela
authors.initials: M
authors.lastname: Lucas
authors.forename: Thillagavathie
authors.initials: T
authors.lastname: Pillay
authors.forename: Kei
authors.initials: K
authors.lastname: Ouchi
authors.forename: Laura L
authors.initials: LL
authors.lastname: Reyor
authors.forename: Julian
authors.initials: J
authors.lastname: Schulze zur Wiesch
authors.forename: Rajesh T
authors.initials: RT
authors.lastname: Gandhi
authors.forename: Raymond T
authors.initials: RT
authors.lastname: Chung
authors.forename: Nina
authors.initials: N
authors.lastname: Bhardwaj
authors.forename: Paul
authors.initials: P
authors.lastname: Klenerman
authors.forename: Bruce D
authors.initials: BD
authors.lastname: Walker
authors.forename: Todd M
authors.initials: TM
authors.lastname: Allen
mesh_terms: D000208:Acute Disease; D000595:Amino Acid Sequence / Q000235:genetics; D019943:Amino Acid Substitution / Q000235:genetics / Q000276:immunology; D000818:Animals; D018414:CD8-Positive T-Lymphocytes / Q000276:immunology*; D002908:Chronic Disease; D018984:Epitopes, T-Lymphocyte / Q000276:immunology*; D019143:Evolution, Molecular; D005260:Female; D014644:Genetic Variation / Q000235:genetics / Q000276:immunology; D015795:HLA-B8 Antigen / Q000276:immunology*; D016174:Hepacivirus / Q000235:genetics / Q000276:immunology*; D006526:Hepatitis C / Q000235:genetics / Q000276:immunology* / Q000473:pathology; D006801:Humans; D008213:Lymphocyte Activation / Q000276:immunology; D008297:Male; D008969:Molecular Sequence Data; D009154:Mutation / Q000235:genetics / Q000276:immunology; D017361:Viral Nonstructural Proteins / Q000235:genetics / Q000276:immunology*; D014766:Viremia / Q000276:immunology / Q000473:pathology; D012697:Serine Endopeptidases; D043583:Nucleoside-Triphosphatase; D053487:DEAD-box RNA Helicases; D000085242:Viral Proteases
chemical_list: D018984:Epitopes, T-Lymphocyte; D015795:HLA-B8 Antigen; D017361:Viral Nonstructural Proteins; C084422:NS3 protein, hepatitis C virus; D012697:Serine Endopeptidases; D043583:Nucleoside-Triphosphatase; D053487:DEAD-box RNA Helicases; D000085242:Viral Proteases