title: Differential susceptibility of peripheral blood CD5+ and CD5- B cells to apoptosis in chronic hepatitis C patients.
abstract: A body of evidence has suggested a close link between chronic hepatitis C virus (HCV) infection and B cell abnormalities, including mixed cryoglobulinemia, rheumatoid factor (RF) production, and lymphoproliferative disorders that may develop into non-Hodgkin's lymphoma. Recent studies have demonstrated the expansion of CD5(+) B cells in the peripheral blood of chronic hepatitis C patients (CHC). As CD5(+) B cells, which are capable of producing autoantibodies and RF, are apparently crucial for the development of HCV-associated pathogenesis, the fate of both the CD5(+) and CD5(-) B cell subsets upon chronic HCV infection is of interest. In this study, the degree to which chronic HCV infection induces apoptosis in each B cell subset was investigated. Our results demonstrated that peripheral CD5(-) B cells were more susceptible to apoptosis than CD5(+) B cells in CHC. Furthermore, plasma levels of IL-4, IL-10, and IL-12 were significantly elevated in CHC, thus suggesting that these interleukins protect CD5(+) B cells from apoptosis. The rationale for the differential susceptibility of distinct B cell subsets in CHC is also discussed with regard to extrahepatic manifestations associated with chronic HCV infection.
authors.affiliation: Department of Research on Blood and Biological Products, 4-7-1 Gakuen, Musashi-Murayama, Tokyo 208-0011, Japan. miz@nih.go.jp
authors.forename: Toshiaki
authors.initials: T
authors.lastname: Mizuochi
authors.forename: Masahiko
authors.initials: M
authors.lastname: Ito
authors.forename: Kenji
authors.initials: K
authors.lastname: Takai
authors.forename: Kazunari
authors.initials: K
authors.lastname: Yamaguchi
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D017209:Apoptosis / Q000276:immunology*; D001402:B-Lymphocytes / Q000276:immunology*; D018956:CD5 Antigens / Q000276:immunology; D016207:Cytokines / Q000097:blood; D005260:Female; D019698:Hepatitis C, Chronic / Q000097:blood / Q000276:immunology*; D006801:Humans; D008297:Male; D008875:Middle Aged
chemical_list: D018956:CD5 Antigens; D016207:Cytokines