Activated natural killer T cells producing interferon-gamma elicit promoting activity to murine dendritic cell-based autoimmune hepatic inflammation.

As natural killer (NK) T cells play an important role in the development of autoimmune diseases, they should have significant roles for the pathogenesis of autoimmune liver disease. Implication of the NK T cells in the generation of autoimmune-related hepatic inflammation was investigated using a novel mouse model. Immunization of mice with dendritic cells (DCs) loaded with hepatocyte-mimicking hepatocellular carcinoma cells (DC/Hepa1-6) induces cytotoxic T lymphocytes (CTL) capable of killing hepatocytes. Subsequent administration of interleukin (IL)-12, a potent interferon-gamma (IFN-γ) inducer, to the immunized mice generates autoimmune hepatic inflammation (AHI), as reported previously. Upon onset of the AHI response, the number of intrahepatic CD3(+) NK1 · 1(+) NK T cells increased markedly, along with a decrease in the number of splenic NK T cells, augmented expression of CXCR6 on intrahepatic NK T cells and CXCL16 in hepatic tissue, suggesting that NK T cells were recruited into the inflamed liver. The NK T cells were strongly positive for CD69 and produced IFN-γ, but not IL-4. AHI activity was attenuated markedly in CD1d(-/-) NK T cell-deficient mice, indicating that NK T cells play a pivotal role in the development of AHI. Mice treated with DC/Hepa1-6 and alpha-galactosylceramide, a potent NK T cell activator, also exhibited similar hepatic inflammation, in which activated NK T cells producing IFN-γ and CD8(+) T cells cytotoxic to hepatocytes were induced in liver-infiltrating mononuclear cells. Activated NK T cells producing IFN-γ potentiate DC-based AHI in the mouse model.

Immunomodulatory effects of selective leucocytapheresis as a new adjunct to interferon-alpha2b plus ribavirin combination therapy: a prospective study in patients with high plasma HCV viraemia.

Efficacy of interferon-alpha2b (IFN) + ribavirin (IFN/RBV) combination in patients with high plasma hepatitis C virus (HCV) is very poor. Dysregulated CD4+ /CD8+ T cells is involved in both impaired cell-mediated immunity and resistance to IFN. Adsorptive granulocytes and monocytes apheresis (GMA) can remove infected leucocytes which are extrahepatic HCV reservoirs and also has been associated with intriguing immunomodulation and increases in CD4+ T cells. Our aim was to see if GMA enhances the efficacy of IFN/RBV. Twenty-four patients, 13 IFN resistant and 11 IFN naive were enrolled. Seventeen were genotype 1b and 7 were 2a or 2b. Mean plasma HCV-RNA was 612.9 (100-850) kIU/mL and alanine aminotransferase, 108 (41-373) U/L. GMA was performed with Adacolumn at one session/day for five consecutive days and IFN/RBV was started within 24 h after the last GMA session. Daily 6 million units of IFN, six times/week for 2 weeks and then three times/week for 22 weeks were given with RBV (600-800 mg/day/patient). Patients were followed for 6 months. GMA was associated with a significant increase in lymphocyte counts, complement activation fragment C3a and falls in tissue necrosis factor-alpha, and IL-8 produced by peripheral blood leucocytes. At week 24, 20 of 24 patients (83%) were HCV negative and by end of follow-up (week 49), the remission was sustained in 14 of 24 patients (58%) including 100% of patients with 2a or 2b. In conclusion, enhanced efficacy of IFN/RBV following GMA might be attributed to a more efficient immune function and a renewed IFN signaling towards HCV.

Rapid decrease of plasma HCV RNA in early phase of twice daily administration of 3 MU doses interferon-beta in patients with genotype 1b hepatitis C infection: a multicenter randomized study.

Virological response to interferon (IFN) is poor in patients with plasma levels of HCV RNA higher than 1 Meq/ml and genotype 1b hepatitis C viral infection. In 60 patients, a randomized control study was conducted to compare 3 MU of IFN-beta twice daily for four weeks (group A) and 6 MU once a day for four weeks (group B) followed by a four-week administration of 6 MU once a day. The plasma levels of HCV RNA, determined by an amplicore-monitor method, for patients in group A were significantly lower than those for group B at the fourth and eighth day of IFN administration, and complete virological responses were noted in two patients from group A but none in group B. It is concluded that twice daily administration of 3 MU IFN-beta is more effective than once a day 6 MU in the early phase of IFN therapy.

Clinical significance of autoantibody to hepatocyte membrane antigen in type 1 autoimmune hepatitis.

OBJECTIVE: By using HepG2 as flow cytometry target, we have reported that autoantibody to hepatocyte membrane antigen (anti-HMA) was frequently found in autoimmune hepatitis (AIH) patients. In this study, we have examined this autoantibody in relation to clinical features in these patients. METHODS: HepG2 cells were incubated with diluted serum and subsequently with FITC-conjugated antihuman immunoglobulin. The results were expressed as relative fluorescence intensity. The prevalence of anti-HMA was estimated by setting the upper limit of mean +/- 3 SD obtained from healthy subjects. RESULTS: We found that the mean relative fluorescence intensity was 1.67+/-0.5 in AIH with low serum ALT level (group 1 AIH), 4.20+/-1.9 in AIH with high serum ALT level (group 2 AIH), and 1.92+/-0.9 in age-matched chronic hepatitis C virus-positive patients. Their positive rate was 37.5% (three of eight) in group 1 AIH, 95.0% (19 of 20) in group 2 AIH, and 33.3% (four of 12) in chronic hepatitis C patients. In 12 group 2 AIH patients, their mean relative fluorescence intensity was significantly decreased during immunosuppressive therapy. The association between serum ALT level and anti-HMA was confirmed by the facts that a significant direct quantitative relationship existed between these two levels and by serial studies of anti-HMA in four AIH patients. Anti-HMA was also detected in five non-B, non-C hepatitis patients having clinical features resembling those of AIH. CONCLUSIONS: The present results have shown that the anti-HMA was tightly associated with the degree of hepatocyte inflammation and that the measurement of anti-HMA may have some advantage in clinical evaluation of some of non-B, non-C hepatitis patients.

Case selection for interferon treatment of hepatitis C.

To establish a case selection algorithm for the treatment of hepatitis C, predictive factors were studied and reported articles were reviewed and analysed. Because of the relatively poor efficacy of interferon (IFN) monotherapy, which is ineffective in 60-70% of patients, case selection at present is determined by the likelihood of attaining a sustained response (SR; defined by normalizing serum ALT and eliminating serum HCV RNA after treatment) to therapy. According to the present study, viral load and genotype, and IL-10 and IL-1ra serum levels, are the most predictive of achieving SR after IFN monotherapy given in a comparatively high dose regimen for 6 months. In addition, reported studies with logistic analyses were carefully reviewed and analysed for the most effective predictive factors of case selection. The results again indicated that viral load and HCV-genotype (serotype). were closely related to SR. Age, gender, and histological changes at treatment were also considered for case selection. These results, however, relate solely to IFN-monotherapy. Future development of more effective strategies for treating hepatitis C could alter the exclusion criteria for IFN treatment and will negate the need for the case selection algorithm discussed here.

Analysis of factors affecting the appearance of hepatocellular carcinoma in patients with chronic hepatitis C. A long term follow-up study after histologic diagnosis.

BACKGROUND: Hepatocellular carcinoma (HCC) occurs more frequently in patients with hepatitis C virus (HCV)-related chronic liver disease than those with hepatitis B virus-related disease. It is important to assess the factors affecting the development of HCC. METHODS: A long term follow-up study involving patients with chronic HCV was performed retrospectively. A total of 153 patients diagnosed between June 1981 and November 1990 with chronic HCV with or without cirrhosis by liver biopsy were enrolled in a long term follow-up study (average, 99.4 months) and the cumulative incidence rate of HCC and factors affecting the appearance of HCC were examined. RESULTS: The 5-year cumulative incidence rate was 9%, the 10-year cumulative incidence rate was 23%, and the 15-year cumulative incidence rate was 42%. The annual rate of incidence increased as the follow-up period progressed. The authors selected ten variables and investigated their effect on the incidence rate of HCC, including age, gender, habitual heavy drinking, positivity of antibody against hepatitis B virus surface antigen, treatment with interferon (IFN) during the follow-up period, maximum and minimum serum alanine aminotransferase levels during the follow-up period, histologic staging, grading, and irregular regeneration of hepatocytes. Of the 10 variables, age (> 50 years), habitual heavy drinking, and histologic staging were determined to be independent risk factors according to multivariate Cox proportional hazards regression analysis. IFN therapy by itself was not found to be an independent factor affecting the appearance of HCC. CONCLUSIONS: In patients with chronic HCV, the annual incidence rate of HCC appeared to increase as the follow-up period progressed. According to the results of the current study, the factors that independently affected the development of HCC were age, habitual heavy drinking, and histologic staging.

[Thyroid disease in autoimmune liver diseases].

It has been reported that autoimmune liver diseases, autoimmune hepatitis, primary biliary cirrhosis and primary sclerosing cholangitis, complicate thyroid disorder. According to the Nationwide survey in Japan, hypothyroidism most of which are due to chronic thyroiditis was seen in both autoimmune hepatitis and primary biliary cirrhosis, at 12% and 5.8%, respectively. It is sometimes happen that the manifestation of thyroid disorder proceeds the symptoms of liver disease. Because middle-aged women preferably tend to suffer from both autoimmune liver disease and autoimmune thyroid disease, it is important that we should be concerned both diseases when we are making diagnosis in these patients.

Association between frequency of amino acid changes in core region of hepatitis B virus (HBV) and the presence of precore mutation in Japanese HBV carriers.

To elucidate the relationship between the frequency of core mutations and precore mutation of hepatitis B virus (HBV) in Japanese HBV carriers, we investigated the nucleotide sequence of the precore/core region of HBV in 26 Japanese HBV carriers [15 who were HBe antigen-negative (HBeAg-) and 11 who were HBeAg-positive (HBeAg+)]. The number of amino acid changes (5.9 +/- 3.8) in the core region of HBV in HBeAg-carriers was significantly greater than that in the HBeAg+ carriers (1.5 +/- 1.0; P < 0.005). The precore stop codon mutation was found in 93.3% of HBeAg-negative HBV carriers, while no precore mutation was found in the HBeAg-positive HBV carriers, suggesting that the frequency of core mutations may be associated with the presence of the precore stop codon mutation. However, there was no significant difference in the frequency of amino acid changes among HBeAg-HBV carriers. The mean number of core amino acid changes of liver cirrhosis patients, chronic active hepatitis patients, chronic persistent hepatitis patients, and asymptomatic carriers were 2.7 +/- 1.5, 6.0 +/- 2.2, 4.7 +/- 1.2, and 8.4 +/- 5.3, respectively. We detected hot spots for core mutations, which showed characteristic localizations and specific substitutions: Gly-87, Leu-97, and Thr-130 were detected exclusively in patients with chronic liver disease with or without HBeAg. To address further the relationship between frequency of core mutations and the presence of the precore stop codon mutation, we investigated the precore/core nucleotide sequence serially along with seroconversion in three patients with chronic hepatitis B in whom the hepatitis either became inactive or remained active after the seroconversion. Emergence of the precore stop codon mutation and a significant increase in core amino-acid changes after seroconversion were noted in all three patients. Our results suggest a close association between the frequency of core amino acid changes and the presence of the precore stop codon mutation; some characteristic core mutations may be associated with the clinical course of chronic hepatitis B in Japanese patients.

Present status of autoimmune hepatitis in Japan--correlating the characteristics with international criteria in an area with a high rate of HCV infection. Japanese National Study Group of Autoimmune Hepatitis.

BACKGROUND/AIMS: A nationwide survey of autoimmune hepatitis (AIH) was carried out in Japan. METHODS: Four hundred and ninety-six patients were enrolled by questionnaires sent to 101 hospitals with hepatology specialists. RESULTS: The clinical features of Japanese AIH were as follows: most patients were middle-aged women; serum autoantibodies, especially antinuclear antibody, were frequently positive, serum IgG level was high, and HLA-DR4 was the major HLA allotype. Liver-kidney microsomal type 1 antibody was positive in nine of 79 patients tested. Eight of these antibody positive patients were also positive for antinuclear antibody and five for anti-smooth muscle antibody. Ninety-two percent of the patients showed piecemeal necrosis and 60% bridging necrosis; plasma cell infiltration in the portal areas was observed in 50% of the patients. Only 12.3% were diagnosed as having liver cirrhosis. A favorable effect of corticosteroid, normalization of serum transaminases, was observed in 89% of 317 patients, who were treated with an initial dose of over 30 mg/day. Sixty-two patients were positive for hepatitis C virus (HCV) markers. In these patients, however, only one patient was liver-kidney microsomal type 1 antibody positive. Corticosteroid was effective in 30 (81%) of 37 HCV-marker-positive patients treated with this agent. Thus the efficacy of corticosteroid did not differ from that in AIH patients without HCV infection (90%). Similarly, interferon treatment was used in 20 patients, all of whom were positive for HCV-RNA, and resulted in 50% efficacy as determined by normalization of the serum transaminase level 6 months after treatment. The International Diagnostic Scoring System for the diagnosis of AIH worked well in these patients, except for HCV-infected individuals, that is, approximately 10% of the total of AIH patients.