抄録
Infection with hepatitis C virus (HCV) is associated with lymphoproliferative disorders (LPD). Several abnormalities of LPD markers and clonal expansion of B cells are observed not only in HCV infected patients with LPD but also in asymptomatic patients, suggesting that reliable markers for B cell proliferation are required. Recently, serum B cell activating factor (BAFF) has been reported as a marker of B cell proliferation. Serum BAFF levels in European patients with HCV infection were reported higher than those in healthy subjects. In this study, we assessed serum BAFF levels in 75 Japanese patients with chronic hepatitis C (CH-C) and analyzed the associated factors with high levels of BAFF. Results showed that serum BAFF levels in patients with CH-C were higher than those in control subjects (1,560.5±153.1 vs. 891.4±55.6pg/ml, P < 0.001). Interferon-based therapy rapidly increased levels of BAFF during the therapy. BAFF levels were neither correlated with levels of other LPD markers (cryoglobulinemia, rheumatoid factor, complement 4 and CH50) nor the B-cell clonality. Decreased number of platelets and cirrhosis were correlated with high levels of serum BAFF, suggesting that the progression of liver diseases might induce the release of BAFF. Serum BAFF levels in patients with other liver diseases, autoimmune hepatitis and primary biliary cirrhosis, were also higher than those in controls (AIH, 1,084.8±77.6, P < 0.05; PBC, 1,970.3±202.6pg/ml, P < 0.001). In conclusion, HCV infection and/or the progression of hepatic inflammation stimulate the release of BAFF. This release is further enhanced by interferon which is associated with the development of LPD and autoimmune diseases.
