Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0023890 (cirrhosis)
 42,195 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Structural and nonstructural regions of the HCV-encoded polyprotein have been expressed in recombinant yeast, bacteria, or insect cells and used to capture and measure reactive antibodies circulating in different individuals. The putative nucleocapsid protein (C) and nonstructural proteins 3-5 (NS3-NS5) were found to contain the most immunodominant epitopes. The NS3, NS4, and C regions were expressed in yeast in the form of a fused, chimeric polyprotein (C25) and a capture assay for reactive antibody was developed. This anti-C25 assay detects all previously identified HCV-seropositive cases and provides a substantially more sensitive diagnostic for both acute and chronic HCV infections than the current anti-C100-3 (NS4) assay. Anti-C25 was detected more frequently than anti-C100-3 in chronic, transfusion-associated non-A, non-B hepatitis patients from the United States (95% vs. 71%) and Japan (98% vs. 82%), in cryptogenic cirrhosis patients from the United States (62% vs. 28%), and in hepatitis B surface antigen-negative cases of hepatocellular carcinoma from Japan (83% vs. 63%). These data indicate that HCV has a greater role in these liver diseases than was previously thought. In volunteer United States blood donors sampled following the introduction of anti-C100-3 screening, the prevalence of anti-C25 and anti-C100-3 was 0.5% and 0.08%, respectively.
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PMID:Diagnosis of hepatitis C virus (HCV) infection using an immunodominant chimeric polyprotein to capture circulating antibodies: reevaluation of the role of HCV in liver disease. 127 66

Eighty patients with chronic hepatitis C who completed a previously reported randomized controlled trial on the efficacy of interferon-alpha 2b were followed up for at least 36 mo after therapy discontinuation. Seventeen patients (21.2%) maintained normal ALT values throughout the follow-up; 63 (78.8%) either did not normalize the levels of ALT or relapsed during the follow-up. A significantly greater proportion of patients treated with 3 million units of interferon three times a week subcutaneously for 48 wk were long-term responders compared with patients treated for 24 wk. Sex, age, hepatitis C virus antibody status, source of infection and pretreatment levels of ALT were not predictive of long-term response. Cirrhosis was found to be an unfavorable predictive factor. After 3 yr of follow-up, clearance of viremia was observed in 58.9% of the 17 long-term responders but in none of the non-responders (p = 0.002). E2-NS1 antibody tested negative in 88.2% of long-term responders and in 14.3% of nonresponders (p = 0.001). Fifty-nine percent of long-term responders tested negative for C100-NS4 antibody compared with 14.3% of nonresponders (p = 0.031). No significant change was observed in other antibodies. Four long-term responders underwent liver biopsy 2 yr after discontinuation of therapy. All four patients had normal liver histology compared with baseline assessment of chronic active hepatitis in three and chronic persistent hepatitis in the other. Three of the four were negative for serum hepatitis C virus RNA.
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PMID:Long-term follow-up of patients with chronic hepatitis C treated with different doses of interferon-alpha 2b. 769 94

The presence of the "Japanese type" NS4 region was investigated in two series of patients (53 from Italy and 58 from Japan) with hepatitis C virus (HCV)-related chronic liver disease. The two populations were homogeneous as regard to age, male/female ratio, histological diagnosis, and serum aminotransferase activities. Genomic amplification was carried out by "nested" polymerase chain reaction (PCR) with a pair of primers synthesized according to the sequence of JK-1 isolated in Japan. The presence of viral replication was confirmed further by PCR amplification of the 5'NC region. The NS4 region of the Japanese strain was detected in 24 sera (45%) from Italy and in 44 (71%) from Japan. NS4-positive patients were significantly older and showed an ALT serum level significantly lower (P < 0.01) than NS4 negative cases in each group. Cirrhosis was significantly (P < 0.0007) more common in NS4-positive than in NS4-negative patients. The HCV genotype was subsequently obtained according to Okamoto. All the NS4-positive patients were infected by Type II, whereas in NS4-negative patients all four genotypes were present though Type II still constituted the majority. Cirrhosis was associated exclusively with Type II both in NS4-positive and -negative subjects. These data indicate that, although the positivity for NS4 "Japanese" region seems to be associated with a more aggressive liver disease, the most prevalent Type II predicts more specifically those who are likely to develop cirrhosis.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Different genotypes of hepatitis C virus are associated with different severity of chronic liver disease. 793 Nov 91

Hepatitis C virus (HCV) genotypes (groups I and II) were determined by a newly developed C14 assay in which antibodies against group-specific recombinant proteins of the NS4 region were measured by ELISA (enzyme-linked immunosorbent assay). The genotypes determined by the C14 assay were compared to those determined by a polymerase chain reaction (PCR) in 50 patients. The HCV genotypes determined by both methods were consistent in 78% of the patients. The results of the assays were not contradictory in any patient. The sensitivity of the C14 assay was as high as over 90%. Frequency of HCV genotypes was studied in 300 patients with chronic liver diseases type C by using the C14 assay. The prevalence of groups I and that of II in patients with chronic hepatitis were 73% and 21%, the correspondence figures in those with liver cirrhosis 80% and 13%, and in those with hepatocellular carcinoma 81% and 13%, respectively. The clinical characteristics were similar between the patients with group I and II HCV infections in each disease category. In conclusion, the C14 assay is useful for epidemiological studies of HCV genotypes, and group I is a major HCV genotype of chronic liver diseases type C in Japan.
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PMID:Prevalence of hepatitis C virus with different genotypes determined by a group-specific antibody assay in Japanese patients with chronic liver diseases due to hepatitis C virus infection. 796 59

With current therapeutic regimens, sustained responses occur in no more than 25% of patients with chronic hepatitis C who are treated with interferon. Relapses occur usually within 6 months from therapy suspension, but clinical and virologic recurrencies can be observed as late as after 3 years of follow up. The rate of long-term responses seems to depend on the dosage and the period of administration of interferon, but the best therapeutic protocol remains unknown. As a direct marker of permanent recovery is not available, indirect signs of disease resolution are: (i) continuously normal alanine aminotransferase levels; (ii) clearance of HCV-RNA; (iii) disappearance of anti-C100/NS4; and (iv) significant histological improvements assessed at least 2 years after therapy withdrawal. Known baseline predictive features of long-term response are the absence of cirrhosis, low viraemic levels and infection with HCV of type III or IV genotype (Okamoto's classification). According to recent reports, the lower the heterogeneity of the hypervariable region of the envelope 2 gene of HCV, the higher the chance of a sustained remission. There is not yet any consensus on the efficacy of a second therapeutic course of interferon in inducing a permanent response, and controlled trials are needed to clarify this issue.
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PMID:The long-term efficacy of interferon alfa in chronic hepatitis C patients: a critical review. 858 Apr 12

Infection with the hepatitis C virus (HCV) commonly causes persistent disease, which may lead to cirrhosis and hepatocellular carcinoma. The pathogenesis of HCV infection is not well understood. It is most likely that both viral and host factors contribute to HCV persistence. This review focuses on the host's immune response to HCV in an attempt to present the current knowledge and concepts of the interactions between the virus and the host during HCV infection. Expansion of B lymphocytes and antibody production to virtually any HCV protein can be detected in most infected patients. However, observations in HCV-infected humans as well as experimental infections in chimpanzees suggest that natural HCV infection does not induce protective immunity, and reinfection can readily be demonstrated after inoculation with homologous or independent strains in HCV-seroconverted animals. Nevertheless, the immune system may gain partial control over HCV even in patients with chronic infection, as HCV infection in severely immunocompromised patients runs a particular cholestatic course which may rapidly lead to death from liver failure. Cytotoxic CD8+ T lymphocyte responses to HCV proteins have been characterized in peripheral blood and liver tissue and were found to be remarkably polyclonal and multispecific. Epitopes were identified on all of the putative HCV proteins, although only few major histocompatibility complex molecules were considered restriction elements. Immunoregulation may be particularly important in HCV infection. The HCV core and NS4 proteins appear to be most immunogenic for peripheral blood lymphocytes, and NS4 specific CD4+ lymphocytes are preferentially compartmentalized to the liver. However, there is an inverse relationship between CD4+ lymphocyte responses and antibody levels in infected patients. Furthermore, a strong cellular response to the HCV core protein apparently favors a benign course of infection. This unusual T-B cell relationship may be the consequence of an altered cytokine release during HCV infection. Alternatively, this virus may have found devices that can disturb immunoregulation in infected patients. A better understanding of these immunological mechanisms induced by HCV infection should make it possible to develop more effective strategies for the prevention and treatment of this insidious disease.
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PMID:Immune responses in hepatitis C virus infection. 883 85

Hepatitis C Virus infection accounts for the majority of post-transfusion and sporadic hepatitis. In Western Europe, anti-HCV is detected in 0.4-1.5% of healthy blood donors. There is a high frequency of progressive chronic hepatitis, ranging from 50 to 80%, which leads to cirrhosis in 20-50% of patients after 10-20 years. Viremic patients with minimal biochemical abnormalities may have chronic liver disease histologically. There is growing evidence that virological features of HCV are associated with different clinical manifestations and response to therapy. The RNA genome consists of a 5' and 3' Untranslated Region, a structural domain encoding the core and envelope proteins, and a non-structural domain. Different HCV isolates show a high sequence heterogeneity, which has led to the classification of currently six genotypes and several subtypes. There is a marked difference in the geographic distribution of HCV genotypes, with types 1, 2 and 3a being most frequently found in western countries. In The Netherlands, subtype 1b accounts for approximately 60% of all cases of chronic HCV. Serologic diagnosis based on recombinant C-100 antigens (first generation immunoassays) only reliably detected type 1, due to the heterogeneity of the NS4 region; inclusion of more conserved proteins c22 and c33 (second generation assays) has largely improved sensitivity of anti-HCV testing. Genotype 1b is associated with more severe liver disease and with lower response rates for antiviral therapy, compared with types 2 and 3. Quasispecies nature and escape mutants may enable viral persistence and the development of chronic liver disease. As cross-reactivity between genotypes is unlikely, prevention of HCV disease may be dependent on the development of multivalent vaccines.
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PMID:Hepatitis C virus: biological and clinical consequences of genetic heterogeneity. 886 60

Sixteen medical institutions in Japan collaborated in this study of the epidemiology of hepatitis C virus (HCV) genotypes. A total of 4176 patients with type C chronic liver disease, from the four main islands of Japan, were evaluated. Of those evaluated, 2794 had chronic hepatitis, 727 had liver cirrhosis and 655 had hepatocellular carcinoma. The HCV genotype of the patients was determined by an enzyme-linked immunosorbent assay based on serological genotype 1- and 2-specific recombinant peptides (SG-1 and SG-2, respectively) of the NS4 region. The prevalence of SG-1 and SG-2 HCV was similar in the four main islands of Japan. SG-1 HCV predominated in each disease category (69-76%). The percentage of patients with SG-1 HCV increased by 7%, while that of patients with SG-2 HCV decreased by 7%, as liver disease progressed in severity from chronic hepatitis to carcinoma (P < 0.001). Patients with either SG-1 or SG-2 had a similar mean age and history of blood transfusion. In conclusion, SG-1 HCV was found to predominate in Japan, and the HCV genotype was found to be related to the stage of hepatitis C disease.
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PMID:Epidemiology of genotypes of hepatitis C virus in Japanese patients with type C chronic liver diseases: a multi-institution analysis. 896 29

Evidence is emerging that hepatitis C virus genotypes have different carcinogenic potentials. The hepatocarcinogenicity of genotype 5, the predominant subtype in hepatitis C virus isolates in South Africa, is not known. We have compared the prevalence of genotype 5 of hepatitis C virus in 44 southern African blacks with hepatitis C virus-related hepatocellular carcinoma with that in a comparable group of patients with hepatitis C virus-induced chronic liver disease (cirrhosis or chronic hepatitis) in the absence of cancer. Hepatitis C virus serotypes 1 to 6 were identified by measuring type-specific antibodies to NS4-derived peptide antigens. Serotype 5 was present in 48% (21/44) of the patients with hepatocellular carcinoma and 37% (15/41) of those with liver disease in the absence of hepatocellular carcinoma, an insignificant difference. Although the numbers of the other genotypes were small, the differences in the prevalence rates of these serotypes between the two groups of patients were also not significant. We conclude that genotype 5 of the hepatitis C virus is neither more nor less carcinogenic than other genotypes found in isolates in South Africa.
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PMID:Hepatocarcinogenic potential of genotype 5 of hepatitis C virus. 961 95

Using 4 McAbs to HCV-C, E, NS3 and NS4 regions' antigens and PcAb to HBsAg, 59 cases of hepatocellular carcinoma(HCC) and 35 cases of liver cirrhosis(LC) were tested by immunohistochemistry technique. Positive reactions for hepatitis C virus were mainly present in the cytoplasm of hepatocytes and tumor cells with fine granules. The positive rates of HCV were 17.2% in HCC(29 cases) of Beijing, 26.7% in HCC(30 cases) of Shenyang and 14.3% in LC(35 cases) of Shenyang. C region's McAb had the highest positive rate of detection, which suggested that C region's protein had a high level expression. The positive rates of hepatitis B virus surface antigen were 63.0% in HCC(29 cases) of Beijing, 73.3% in HCC(30 cases) of Shenyang and 54.3% in LC(35 cases) of Shenyang, all of which were higher than their positive rate for HCV detected. In HCC and LC, HBV and HCV inclined to suppress the opposite side.
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PMID:[Detection of hepatitis C virus-C, E, NS3 and NS4 regions' antigens in hepatocellular carcinoma and liver cirrhosis]. 1252 45


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