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The pathogenic mechanisms that lead to chronic hepatitis C are unknown. As hepatitis C virus (HCV) has been shown to induce T cell response, we assessed whether a particular T lymphocyte subset could be preferentially detected in the liver of patients with chronic hepatitis C in relation to viraemia or HCV genotypes. The immunophenotypes of liver-derived lymphocytes were analysed in 26 patients by flow cytometry and immunohistochemistry. Viraemia was quantified by branched DNA assay. Using this assay, HCV RNA was not detectable in six patients. HCV RNA was detected in 20 patients, and titres ranged from 8 to 137 × 106 Eq/ml. Genotyping was performed using a line probe assay. Type 1a, 1b, 2a, 3a and 4a were found to infect 2, 10, 2, 7 and 3 patients, respectively. The CD4+/CD8+ ratio of liver-derived lymphocytes was significantly higher (P < 0.01) in patients with detectable viraemia than in patients without detectable viraemia. In contrast, neither the percentage of γ/δ T lymphocytes nor that of CD2+CD57+ cells was different in the groups. When comparing the CD4+/CD8+ ratio, the percentage of γ/δ T lymphocytes or CD2+CD57+ cells according to genotype, the differences were not significant. These results suggest that the CD4+/CD8+ ratio of liver-derived lymphocytes is related to viraemia but not to HCV genotypes in patients with chronic hepatitis C. [ABSTRACT FROM AUTHOR]

T lymphocytes have been assumed to play an essential role in tissue injury in patients with chronic hepatitis B. As hepatitis B virus (HBV) is considered as a major factor controlling liver inflammation, we assessed whether a particular T lymphocyte subset could be preferentially detected in the liver in accordance with viral replication. Liver-derived lymphocytes and peripheral blood lymphocytes were analysed by flow cytometry in 21 patients with histologically confirmed chronic hepatitis B without cirrhosis. Viral replication was quantified by hybridization of serum HBV DNA. Eleven patients exhibited an active viral replication with serum HBV DNA ranging from 10 to 388 pg/mI at the time of the liver biopsy, whereas 10 patients had no detectable serum HBV DNA. In patients exhibiting viral replication, CD4+/CD8+ ratios of liver-derived lymphocytes were significantly higher (P < 0.05) than those obtained in patients without viral replication. In contrast, the percentage of T cells expressing the γ/δ receptor and that of CD2+/CD57+ cells were similar in both groups of patients. Furthermore, in patients exhibiting viral replication, CD4+/CD8+ ratios of liver-derived lymphocytes correlated with serum HBV DNA levels (P < 0.001). No relationship between CD4+/CD8+ ratio of liver-derived and peripheral blood lymphocytes was observed. Our data indicate that, in patients with chronic hepatitis B. the CD4+/CD8+ ratio of liver-derived lymphocytes correlates with viral replication. This suggests that in situ helper/inducer CD4+ T lymphocytes may positively regulate the cytoxic T cell activity in patients with HBV-related chronic hepatitis. [ABSTRACT FROM AUTHOR]

Polyclonal B cell activity in systemic lupus erythematosus (SLE)may be under T cell control. The use of nitrocellulose irnmunoblots for the analysis of recognition by peripheral blood lymphocytes of nucleoplasmic proteins in SLE patients led to the characterization of significant proliferative responses to 68K (UI RNP): SS-B: B-B' and D (Sm) antigen in 15 of 20 patients. Variations of proliferative response were parallel to disease activity over a follow-up period of &ges; 6 months. conferring some prognostic value to the assay of lymphocyte response to nucleoplasmic antigens. The pattern of reactivity differs from the corresponding serum antibody profile, and purified T cell suspensions ( >95% pure) were shown to proliferate in response to soluble nucleoplasmic antigens, indicating that T and B cell repertoires against nucleoplasmic proteins may differ. This suggests that activated helper T cells contribute to the fine modulation of B cell reactivity to subcellular particles to determine the particular antibody profile of the patients. [ABSTRACT FROM AUTHOR]