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Hepatitis B virus (HBV) clone 4B replicated much more efficiently than clone 2A of the same genotype. Introduction of its T1753C, A1762T, G1764A, and C1766T core promoter mutations into the 2A genome greatly enhanced genome replication and suppressed HBeAg expression. Here we show that these effects are mediated by transcriptional up regulation of pregenomic RNA and suppression of precore RNA. Analysis of chimeric constructs suggested that the 5′ end of the 2A core gene conferred higher level of pregenomic RNA, but less core protein and genome replication relative to the 4B sequence. Genome maturity of secreted virions was reduced by mutations present in the core protein of the 2A genome but enhanced by mutations found in the 4B core protein. The 4B core protein migrated faster than that of clone 2A. The possible links among the various phenotypes and the responsible mutations remain to be established.

Background/Aims We previously reported that hepatitis C virus (HCV) core protein up regulated transcription of apolipoprotein C-IV (ApoC-IV, 10.7-fold increase), a member of the apolipoprotein family implicated in liver steatosis. Here, we identified host transcription factors regulating the ApoC-IV gene expression. Methods Transcriptional regulators were identified by DNA affinity purification and steatosis was detected by oil red O staining and triglyceride assay. Results We defined a 163-bp ApoC-IV promoter as a core protein responsive element, and identified Ku antigen complex (Ku70 and Ku80) as well as nuclear receptors PPARγ/RXRα as key regulators of ApoC-IV gene expression. Both Ku70 overexpression and PPARγ agonist significantly increased ApoC-IV promoter activity; conversely, Ku70 silencing or mutation of PPARγ binding site diminished the ApoC-IV promoter activity. Interestingly, transient transfection of ApoC-IV cDNA into a human hepatoma cell line was able to trigger moderate lipid accumulation. In agreement with this in vitro study, ApoC-IV transcript level was increased in HCV infected livers which correlated with triglyceride accumulation. Conclusions ApoC-IV overexpression may perturb lipid metabolism leading to lipid accumulation. HCV core protein may modulate ApoC-IV expression through Ku antigen and PPARγ/RXRα complex.

Hepatitis C virus (HCV) core protein has been implicated in the development of human hepatocellular carcinoma (HCC). Here we report that expression of HCV core protein by transient transfection increased cell proliferation, DNA synthesis, and cell cycle progression in Huh-7 cells, a human HCC-derived cell line. Culture supernatant from transfected cells also harbored a growth-promoting effect. Moreover, a full-length HCV replicon, but not a subgenomic replicon devoid of the core gene, significantly stimulated growth of transiently transfected Huh-7.5 cells. However, growth of the subgenomic replicon-containing Huh-7.5 cells could be stimulated by secondary transfection with core gene but not other structural genes present in the full-length replicon. Microarray analysis revealed threefold or more transcriptional changes in 372 of 12,500 known human genes in core protein expressing Huh-7 cells, with most genes involved in cell growth or oncogenic signaling, being upregulated rather than downregulated. Of particular interest is the marked upregulation of both wnt-1 and its downstream target gene WISP-2. Indeed, small interfering RNA against wnt-1 blunted growth stimulation by core gene, whereas transfection of Huh-7 cells with the wnt-1 gene sufficed to promote cell proliferation. Consistent with secretion of the wnt-1 protein, conditioned medium from wnt-1 transfected cells accelerated cell growth. In conclusion, HCV core protein induces Huh-7 cell proliferation whether alone or in the context of HCV replication, which is at least partly mediated by transcriptional upregulation of growth-related genes, in particular wnt-1.

A prolonged severe hepatitis of unknown etiology was treated with Inchinko-to, a Chinese herbal medicine, and this case is herein described. Inchinko-to was given with ursodeoxycholic acid (UDCA) and glycyrrhizin. The improvement in the patient's liver function seemed to be accelerated after the treatment, especially after stopping the administration of kanamycin sulfate which might possibly inhibit the conversion of geniposide, one of the constituents of Inchinko-to, to an active ingredient through the suppression of the bacterial growth in intestinal flora, suggesting the usefulness of Inchinko-to for treatment of severe hepatitis.

Objective: Hepatitis C virus (HCV) RNA titer and HCV genotype are considered to be major determinants of the outcome of interferon monotherapy. To clarify whether interferon monotherapy is really effective in patients with the appropriate viral parameters, we prospectively examined these parameters and treated the patients with interferon monotherapy. Methods: Sixty-four patients with an HCV RNA titer 100 kIU/ml and genotype 1 were also enrolled as controls. All patients were treated with 10 megaunits of interferon-α2b every day for 2 weeks and then 3 times a week for 24 weeks. Results: Of the 64 patients with either HCV RNA 100 kIU/ml and genotype 1 were virologic sustained responders (p < 0.001). Conclusion: Our current study showed that the patients with HCV RNA

The role of hepatitis B virus (HBV) in carcinogenesis of hepatitis B surface antigen (HBsAg)-negative, anti-hepatitis C virus (anti-HCV)-positive hepatocellular carcinoma (HCC) remains unknown. To investigate the state of HBV DNA in such HCC, HBV DNA was examined by polymerase chain reaction (PCR) between HBV DNA and human Alu sequence (HBV-Alu PCR), which could detect integrated form of HBV DNA only, and by conventional HBV PCR, which could detect both integrated and episomal forms of HBV DNA. In all the 17 HBsAg-positive HCC, HBV DNA was detected by both HBV-Alu PCR method and conventional HBV PCR method. By contrast, in HBsAg-negative, anti-HCV-positive cases, HBV DNA was detected in 10 of 21 (47.6%) by conventional HBV PCR and in none of 21 (0%) by HBV-Alu PCR method. Thus, integrated form of HBV DNA was not found in most HbsAg-negative, anti-HCV-positive HCC in the current study. The role of episomal form of HBV DNA requires further investigation of its involvement in the process of the development of HBsAg-negative, anti-HCV-positive HCC.

Recently, transfusion-transmitted virus (TTV) was discovered to be a potential causative agent for non-A-E hepatitis. Little is known about the relation between TTV and the clinical courses of various types of acute viral hepatitis. One hundred twenty-five patients with acute viral hepatitis who were admitted to the Chiba University Hospital between 1984 and 1998 and 100 persons with normal liver function tests were tested for the presence of TTV in their sera. Serum samples were tested for TTV DNA and genotype by polymerase chain reaction (PCR). TTV DNA was detected in 15 of 35 patients (43%) with non-A-E hepatitis, 14 of 33 patients (42%) with hepatitis C, 8 of 28 patients (29%) with hepatitis A, 7 of 29 patients (24%) with hepatitis B, and 37 of 100 subjects with normal liver function tests (37%). The detection rate did not differ statistically between non-A-E hepatitis and hepatitis A, B, C, or controls. The distribution of TTV genotypes was similar in non-A-E, A, B, C types, and controls. The clinical characteristics of the acute illnesses were similar for patients with or without TTV in hepatitis non-A-E, A, B, or C. Although TTV was detected frequently in non-A-E acute hepatitis, no etiologic role for TTV could be established.

The quantitation of serum levels of hepatitis C virus RNA in chronic hepatitis C has been regarded as one of the most important indicators for the outcome of interferon therapy. A new method was used for quantitating the copy number of hepatitis C virus RNA using TaqMan polymerase chain reaction and for comparing the ability and usefulness of this assay with Amplicor Monitor assay in 138 patients. The detection range of hepatitis C virus RNA by TaqMan polymerase chain reaction was from 2 × 103 to 2 × 108 copies/ml. Hepatitis C virus RNA was detectable in 128 cases (92.8%) and undetectable in 10 cases (7.2%) by this method. The RNA levels measured by Amplicor Monitor assay correlated significantly with those measured by TaqMan polymerase chain reaction assay and the sensitivity of the two assays was almost equal. Thus, TaqMan polymerase chain reaction assay appears sufficiently sensitive for the evaluation of hepatitis C virus RNA and would be useful for the diagnosis and management of hepatitis C virus infection. J. Med. Virol. 58:121–126, 1999. © 1999 Wiley-Liss, Inc.

Background/Aims: Although GB virus C (GBV-C) is frequently detectable in patients with liver diseases, it is not known whether it actually replicates in the liver. Therefore we have quantitatively examined the strand-specific RNA of this virus. Methods: Fourteen patients (two GBV-C RNA only seropositive, seven both GBV-C RNA and HCV RNA seropositive, and five HCV RNA only seropositive) were examined. Extracted RNAs from sera and liver specimens of these patients were serially diluted and strand-specific RNAs of GBV-C and HCV were quantitatively measured using strand-specific primers by reverse transcription-polymerase chain reaction. Results: Positive-strand GBV-C RNA in serum was detected in all nine GBV-C RNA seropositive cases, and negative-strand RNA was detected in three, uncertain in three, and undetected in three. Positive-strand GBV-C RNA in the liver was detected in seven and undetected in two, while negative-strand RNA in the liver was undetected in eight and uncertain in one. On the other hand, positive-strand HCV RNA was detected in serum from all 12 HCV RNA seropositive patients and negative-strand HCV RNA was detected in one, uncertain in seven, and undetected in four. Positive-strand HCV RNA was detected in the liver from all 12 HCV RNA seropositive patients, and the presence of negative-strand HCV RNA in the liver was confirmed in 10 and uncertain in the remaining two. Conclusion: GBV-C is considered to be far less hepatotropic than HCV, and it is suggested that GBV-C might not be replicating in the liver.

In November 1989, the Japanese Red Cross began screening blood donors for the hepatitis C virus antibody (anti-HCV) by first-generation assay and high-titer hepatitis B virus core antigen antibody. A significant reduction in the incidence of acute posttransfusion hepatitis was reported; however, the incidence still ranged from 2 percent to 4 percent. The Red Cross changed to the second-generation assay in February 1992, the objective being the complete elimination of potential posttransfusion hepatitis. The aim was to elucidate the advantage of second-generation assay as a blood-donor screening test. The incidence of posttransfusion hepatitis after the introduction of second-generation assay was compared with that before the introduction of the first-generation assay and with that during its use. The incidence of posttransfusion hepatitis was 9.6 percent (216/2,240) before anti-HCV-s donor screening. It was 3.7 percent (24/655) and 0.9 percent (3/326) after the introductions of the first- and second-generation hepatitis C virus (HCV) assays, respectively (chi (2) = 50.0, P < .01). Blood-donor screening by second-generation anti-HCV provided a significant benefit compared with the first-generation assay.

Analysis of X-chromosome inactivation patterns in women has been used to assess the clonality of various tumors. In this report, we analyzed 27 liver tumors in women, including 18 samples obtained by the performance of ultrasonically guided thin-needle biopsies. By analysis of the heterogeneity of phosphoglycerate kinase gene, 11 of 27 (41%) cases were found to be heterozygous at the gene. Of these informative 11 cases with liver tumors, 7 cases were “large” tumors (>25 mm in diameter) and 4 cases were “small” tumors (

Background: Hepatitis C virus (HCV) is an important etiologic agent for chronic liver diseases. Methods: The aim of this study was to evaluate the clinical usefulness of second-generation HCV core antigen assay by comparing the results of the assay with those of the COBAS AMPLICOR HCV MONITOR version 2.0 (COBAS v2.0). Results: HCV core antigen was detectable by this assay in 142/149 (95.3%) of serotype 1 (3821±322 fmol/l; mean±SD), in 56/58 (96.6%) of serotype 2 (2589±449 fmol/l), and in 6/6 (100%) of serotypes 1+2 (1240±548 fmol/l). The HCV core antigen levels measured by this assay correlated well with the HCV RNA levels by COBAS v2.0 (r=0.848, P

Background: Previous studies have shown that the development of hepatic failure was found more frequently than that of hepatocellular carcinoma (HCC) in patients with chronic hepatitis C in the United States and European countries. We investigated the status in Japan in a retrospective cohort study. Methods: The incidences of HCC and hepatic failure were accessed in 459 patients with biopsy-proven C-viral chronic liver disease with a mean follow-up period of 8.9±3.2 years and the cause of death was also analyzed in the cohort. Results: HCC developed in 63 patients, 46 of 355 interferon (IFN)-treated and 17 of 104 untreated patients. In contrast, the development of hepatic failure was found in 18 patients, 12 of 355 IFN-treated and six of 104 untreated patients. HCC developed in four of 116 with sustained virological response (SVR), and hepatic failure developed in one of them. Thirty-two of 63 patients developing HCC and eight of 18 patients developing hepatic failure died. Conclusions: Development of hepatic failure was less frequent than that of HCC in Japan. It is important for a favorable prognosis of patients with C viral chronic liver disease to achieve a higher SVR and thus inhibit the development of HCC in Japan.

Hepatitis B virus (HBV) variants with impaired expression of e antigen (HBeAg) frequently arise at the chronic stage of infection, as exemplified by precore and core promoter mutants. Since an intramolecular disulfide bond maintains the secondary structure of HBeAg, we explored effect of missense mutations of either cysteine codon. Consistent with earlier reports, substitution of each cysteine rendered HBeAg nearly undetectable. With underlying nucleotide changes at the loop of pregenome encapsidation signal, the C-7 mutants were severely impaired in pregenomic RNA packaging and hence DNA replication. Although none of the missense mutations at C61 reduced DNA replication, replacement with arginine, but not alanine, aspartic acid, phenylalanine, or serine, blocked virion secretion. Consistent with the detection of C61R genome from a patient serum, secretion block of the C61R mutant could be overcome by co-expression of wild-type core protein. In conclusion, point mutations of the C61 codon may generate viable HBeAg-negative variants.

Hepatitis C virus related liver disease is one of the major cause of death in Japan. To evaluate the effect of interferon (IFN) therapy on survival, the prognosis of 459 patients with C-viral liver disease was examined. During the mean follow-up period of 8.2 years, 33 (9%) of 355 IFN-treated and 15 (14%) of 104 untreated patients died. Liver-related death, especially by HCC, was the main cause of death. IFN treatment decreased the risk for overall death to approximately a half and that for liver-related death to one fifth compared to untreated patients. The standardized mortality ratio for liver-related death was reduced to 0.4 by the IFN-treatment. This reduction was prominent in sustained virological responders. Thus, a long-term clinical benefit was expected from IFN therapy by reducing liver-related death, especially in sustained virological responders.

Most South African hepatitis B virus strains harbor point mutations immediately upstream of the precore AUG codon. The aim of this study was to determine their effect on hepatitis B e antigen expression.The hepatitis B virus DNA sequence around the precore region was determined from sera of 45 black South Africans. The South African mutations were introduced into hepatitis B virus dimers of the same genotype, and hepatitis B e antigen was quantified from culture medium of transfected HepG2 or Huh7 cells.The South African sequence changes were easily detectable in the acute, hepatitis B e antigen-positive phase of infection, suggesting that they were stable traits and were not selected by immune pressure. Triple mutations at the -5, -3, and -2 positions of the AUG codon severely impaired hepatitis B e antigen expression (P0.001). The frequent double mutation at the -5 and -2 positions moderately reduced hepatitis B e antigen levels (P0.001) to an extent comparable to that of the common core promoter mutations (1762(T)1764(A)). The presence of both South African and core promoter mutations diminished hepatitis B e antigen expression in an additive manner. It is interesting to note that the triple South African mutations enabled core protein translation from precore messenger RNA, which could rescue the replication defect of a hepatitis B virus genome with an ablated core gene.We have identified a novel class of hepatitis B e antigen variants with reduced hepatitis B e antigen translation by a ribosomal leaky scanning mechanism. Reduction in hepatitis B e antigen expression may contribute to accelerated seroconversion from hepatitis B e antigen to its antibody in black South Africans infected with hepatitis B virus very early in life.

The core promoter mutants of hepatitis B virus (HBV) emerge as the dominant viral population at the late HBeAg and the anti-HBe stages of HBV infection, with the A1762T/G1764A substitutions as the hotspot mutations. The double core promoter mutations were found by many investigators to moderately enhance viral genome replication and reduce hepatitis B e antigen (HBeAg) expression. A much higher replication capacity was reported for a naturally occurring core promoter mutant implicated in the outbreak of fulminant hepatitis, which was caused by the neighboring C1766T/T1768A mutations instead. To systemically study the biological properties of naturally occurring core promoter mutants, we amplified full-length HBV genomes by PCR from sera of HBeAg + individuals infected with genotype A. All 12 HBV genomes derived from highly viremic sera (5 × 10 9 to 5.7 × 10 9 copies of viral genome/ml) harbored wild-type core promoter sequence, whereas 37 of 43 clones from low-viremia samples (0.2 × 10 7 to 4.6 × 10 7 copies/ml) were core promoter mutants. Of the 11 wild-type genomes and 14 core promoter mutants analyzed by transfection experiments in human hepatoma cell lines, 6 core promoter mutants but none of the wild-type genomes replicated at high levels. All had 1762/1764 mutations and an additional substitution at position 1753 (T to C), at position 1766 (C to T), or both. Moreover, these HBV clones varied greatly in their ability to secrete enveloped viral particles irrespective of the presence of core promoter mutations. High-replication clones with 1762/1764/1766 or 1753/1762/1764/1766 mutations expressed very low levels of HBeAg, whereas high-replication clones with 1753/1762/1764 triple mutations expressed high levels of HBeAg. Experiments with site-directed mutants revealed that both 1762/1764/1766 and 1753/1762/1764/1766 mutations conferred significantly higher viral replication and lower HBeAg expression than 1762/1764 mutations alone, whereas the 1753/1762/1764 triple mutant displayed only mild reduction in HBeAg expression similar to the 1762/1764 mutant. Thus, core promoter mutations other than those at positions 1762 and 1764 can have major impact on viral DNA replication and HBeAg expression.

The quantitation of serum levels of hepatitis C virus (HCV) RNA in chronic hepatitis C has been regarded as one of the most important indicators for the outcome of interferon (IFN) therapy. The AMPLICOR HCV MONITOR version 1.0 (AMPLICOR v1.0) assay is widely used for the evaluation of the HCV level. A new generation assay called the COBAS AMPLICOR HCV MONITOR version 2.0 (COBAS v2.0) assay, which is semiautomated and modified to amplify all genotypes equally, has been developed. The aim of this study was to evaluate the clinical relevance of the COBAS v2.0 assay in comparison with the AMPLICOR v1.0 assay and HCV core protein assay in patients with chronic hepatitis C before IFN therapy. HCV RNA was detectable in 230 cases (97.5%) and undetectable in 6 cases (2.5%) by the COBAS v2.0 assay. The RNA levels measured by the AMPLICOR v1.0 assay correlated significantly with those measured by the COBAS v2.0 assay, and the sensitivity of the new version 2.0 assay was better than that of version 1.0, especially in serotype 2. In relation to the outcome of IFN therapy, HCV RNA levels from virologically sustained responders by the AMPLICOR v1.0 assay were 82.3 ± 22.9 kcopies/ml in serotype 1 and 36.9 ± 13.4 kcopies/ml in serotype 2, and those from virologically nonsustained responders were 525.2 ± 48.6 kcopies/ml in serotype 1 and 76.7 ± 19.5 kcopies/ml in serotype 2.The rates of sustained response to