Expansion of peripheral blood CD5+ B cells is associated with mild disease in chronic hepatitis C virus infection.
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.
Curry
M P
MP
The Liver Unit, St Vincent's Hospital, Dublin, Ireland.
Golden-Mason
L
L
Nolan
N
N
Parfrey
N A
NA
Hegarty
J E
JE
O'Farrelly
C
C
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
D018941:Antigens, CD19; D018956:CD5 Antigens; D012367:RNA, Viral; D012217:Rheumatoid Factor