title: Expansion of peripheral blood CD5+ B cells is associated with mild disease in chronic hepatitis C virus infection.
abstract: OBJECTIVE
  Hepatitis C virus (HCV) infection is associated with the development of chronic liver disease and extra-hepatic manifestations, which include autoantibody production, immune-mediated diseases such as cryoglobulinaemia and B-cell lymphoproliferation. Recent identification of intra-hepatic clonal B cells capable of rheumatoid factor production, selective infection of B cells over T cells and of an HCV receptor on B lymphocytes strongly supports a central role for these cells in the immune response to HCV infection. In particular, CD5+ B cells which are capable of producing natural antibodies with autoreactive specificities are likely to be important in the development of HCV-associated autoimmunity and lymphoproliferation.
  
  
  METHODS
  We have investigated the presence of CD5+ B cells in a unique cohort of HCV-infected women who were infected with a single inoculum of HCV genotype 1b following immunisation with contaminated anti-D immunoglobulin in 1977.
  
  
  RESULTS
  CD5+ B cells are significantly increased in chronic HCV infection (37.66+/-1.92%) as compared with those with resolved infection (25.33+/-1.90%). High levels of CD5+ B cells were associated with the production of rheumatoid factor. The number of peripheral blood CD5+ B cells correlated negatively with histological activity index.
  
  
  CONCLUSIONS
  The expansion of this B cell population in patients with active HCV infection may give rise to immune-mediated sequelae associated with HCV infection. This expanded population of CD5+ B cells may protect against the development of progressive liver disease.
authors.affiliation: The Liver Unit, St Vincent's Hospital, Dublin, Ireland.
authors.forename: M P
authors.initials: MP
authors.lastname: Curry
authors.forename: L
authors.initials: L
authors.lastname: Golden-Mason
authors.forename: N
authors.initials: N
authors.lastname: Nolan
authors.forename: N A
authors.initials: NA
authors.lastname: Parfrey
authors.forename: J E
authors.initials: JE
authors.lastname: Hegarty
authors.forename: C
authors.initials: C
authors.lastname: O'Farrelly
mesh_terms: D000328:Adult; D018941:Antigens, CD19 / Q000032:analysis; D001402:B-Lymphocytes / Q000276:immunology*; D018956:CD5 Antigens / Q000276:immunology*; D005260:Female; D005434:Flow Cytometry; D016174:Hepacivirus / Q000235:genetics / Q000276:immunology*; D019698:Hepatitis C, Chronic / Q000097:blood / Q000276:immunology* / Q000473:pathology; D006801:Humans; D008099:Liver / Q000276:immunology; D008875:Middle Aged; D016133:Polymerase Chain Reaction; D012367:RNA, Viral / Q000032:analysis; D012217:Rheumatoid Factor / Q000097:blood
chemical_list: D018941:Antigens, CD19; D018956:CD5 Antigens; D012367:RNA, Viral; D012217:Rheumatoid Factor