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Virus Markers (virus + marker)

Distribution by Scientific Domains
Medical Sciences50%

Kinds of Virus Markers

  • b virus marker
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  • hepatitis b virus marker
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    Selected Abstracts

    Serum hepatitis B surface antigen and hepatitis B e antigen titers: Disease phase influences correlation with viral load and intrahepatic hepatitis B virus markers,,

    HEPATOLOGY, Issue 6 2010
    Alexander J.V. Thompson
    Although threshold levels for hepatitis B surface antigen (HBsAg) and hepatitis B e antigen (HBeAg) titers have recently been proposed to guide therapy for chronic hepatitis B (CHB), their relationship to circulating hepatitis B virus (HBV) DNA and intrahepatic HBV replicative intermediates, and the significance of emerging viral variants, remains unclear. We therefore tested the hypothesis that HBsAg and HBeAg titers may vary independently of viral replication in vivo. In all, 149 treatment-naďve CHB patients were recruited (HBeAg-positive, n = 71; HBeAg-negative, n = 78). Quantification of HBeAg and HBsAg was performed by enzyme immunoassay. Virological characterization included serum HBV DNA load, HBV genotype, basal core promoter (BCP)/precore (PC) sequence, and, in a subset (n = 44), measurement of intrahepatic covalently closed circular DNA (cccDNA) and total HBV DNA, as well as quantitative immunohistochemical (IHC) staining for HBsAg. In HBeAg-positive CHB, HBsAg was positively correlated with serum HBV DNA and intrahepatic cccDNA and total HBV DNA (r = 0.69, 0.71, 0.76, P < 0.01). HBeAg correlated with serum HBV DNA (r = 0.60, P < 0.0001), although emerging BCP/PC variants reduced HBeAg titer independent of viral replication. In HBeAg-negative CHB, HBsAg correlated poorly with serum HBV DNA (r = 0.28, P = 0.01) and did not correlate with intrahepatic cccDNA nor total HBV DNA. Quantitative IHC for hepatocyte HBsAg confirmed a relationship with viral replication only in HBeAg-positive patients. Conclusion: The correlation between quantitative HBsAg titer and serum and intrahepatic markers of HBV replication differs between patients with HBeAg-positive and HBeAg-negative CHB. HBeAg titers may fall independent of viral replication as HBeAg-defective variants emerge prior to HBeAg seroconversion. These findings provide new insights into viral pathogenesis and have practical implications for the use of quantitative serology as a clinical biomarker. (HEPATOLOGY 2010) [source]

    Perinatal and intrafamily transmission of hepatitis B virus in three generations of a low-prevalence population

    JOURNAL OF MEDICAL VIROLOGY, Issue 2 2003
    Katalin Ördög
    Abstract Family members of 47 hepatitis B virus (HBV)-carrier pregnant women were tested for the presence of hepatitis B surface antigen (HBsAg), other markers of HBV infection, and hepatitis A virus (HAV) antibodies. Eleven members of six families were found to be HBV DNA positive. Five of the anti-HBe-positive persons were found to be HBV DNA carriers, too. The mean age of the HBV DNA carriers was found to be lower than that of Hbe carriers; therefore, it is suggested that seroconversion to HBe occurs before the resolution of HBV DNA carrier state. Superinfection with hepatitis A virus was not found to influence the elimination of HBV-carrier state, as there was no correlation found between the hepatitis A exposure and the hepatitis B virus markers in the families. The low HBV prevalence in the population (0.3%) was in contrast to the high prevalence of the families of the HBV-carrier mothers (27.1%) and family members with HBV markers (50.4%). Significant positive correlation was found in the proportion of HBV-positive children, and the HBV history of their parents. When fathers were shown to be seronegative, the probability of HBV transmission was reduced by a factor of 6 (12.5% instead of 75%) probably due to reduced viral load and possibly by other factors. Several results indicate, that the noncytocidal hepatitis B virus clearing mechanism suggested by Guidotti et al. [1996, 1999] was effective also in the HBV-carrier human population. J. Med. Virol. 70: 194,204, 2003. © 2003 Wiley-Liss, Inc. [source]

    Hepatitis B virus markers in anti-HBc only positive individuals,

    JOURNAL OF MEDICAL VIROLOGY, Issue 3 2001
    Bernard Weber
    Abstract Isolated reactivity to hepatitis B virus (HBV) core antigen (anti-HBc) is observed relatively frequently in immunocompromised individuals, intravenous drug abusers (IVDA), and in the presence of HCV infection. The reason for the lack of HBsAg is not clear. The aim of the present study was to investigate which factors (genetic variability of S gene, low-level HBsAg, and immune complexes may be responsible for the failure of HBsAg detection with commercial HBsAg screening assays. Dilution series of two recombinant HBsAg escape mutants and dilutions of serum samples from chronic HBV carriers with multiple insertions in the a determinant and different HBsAg subtypes were tested with a highly sensitive assay that detects wild-type HBsAg (Elecsys HBsAg, Roche Diagnostics, Penzberg, Germany) and two assays that detect HBV wild-type and escape mutants (Murex HBsAg Version 3, Murex and Enzygnost HBsAg 5.0, Dade Behring, Marburg, Germany). Elecsys HBsAg showed in comparison to Murex HBsAg Version 3 and Enzygnost HBsAg 5.0 a reduced sensitivity for escape mutant detection. On the other hand, the best performance for HBsAg subtype detection was obtained with Elecsys HBsAg. In the second part of the study, a selected panel of isolated anti-HBc reactive (n,=,104) serum samples (AxSYM Core) was submitted to testing by Elecsys HBsAg, Murex HBsAg Version 3, Enzygnost HBsAg 5.0, and HBsAg detection after immune complex dissociation (ICD) and anti-HBs determination with two different assays (AxSYM Ausab and Elecsys Anti-HBs). To assess the specificity of anti-HBc test results, all the samples were tested by a second anti-HBc assay (Elecsys Anti-HBc). Quantitative HBV DNA detection was undertaken with a commercially available HBV PCR assay (Amplicor HBV Monitor). HCV infection was present in 65.4% of anti-HBc only reactive individuals. Five AxSYM Core positive samples were negative by Elecsys Anti-HBc. Overall, 15 (14.4%) AxSYM Ausab negative samples gave positive results with Elecsys Anti-HBs (median value: 21 IU/ml). No low-level HBsAg carrier was detected among the isolated anti-HBc reactive individuals with Elecsys HBsAg. There was no evidence for the presence of immune complexes. Only one sample was repeatedly reactive by the Murex HBsAg, suggesting that the a mutant form of HBsAg was responsible for the isolated anti-HBc reactivity, however neutralisation assay was not interpretable and HBV DNA PCR was negative. Fifteen (14.4%) anti-HBc only positive individuals were HBV DNA carriers with concentrations ranging from 800 to more than >4,000,000 copies of viral DNA/ml. In conclusion, the most probable explanations for isolated anti-HBc reactivity in our study group are a possible interference of HBsAg synthesis by HCV infection (65.4%) and divergence of results of anti-HBs assays (14.4%). There is no evidence for the presence of low-level HBsAg carriers and immune complexes. HBsAg mutants cannot be excluded definitively by the test strategy used in the present evaluation. J. Med. Virol. 64:312,319, 2001. © 2001 Wiley-Liss, Inc. [source]

    Hepatitis C virus infection in Egyptian children: single centre experience

    JOURNAL OF VIRAL HEPATITIS, Issue 5 2004
    M. S. El-Raziky
    Summary., The outcome of hepatitis C virus (HCV) infection acquired in childhood is uncertain because of the diversity of the epidemiological and clinical features of infection and disease. The aim of this study was to determine the outcome of HCV infection in 105 Egyptian children who tested positive for HCV antibody (anti-HCV). The data of 105 anti-HCV-positive children presenting to the Pediatric Hepatology Unit, Cairo University Children's Hospital, between 1995 and 2002, were retrospectively analysed for risk factors. Seventy-four children with available polymerase chain reaction results were further analysed clinically, serologically and histologically. The age range was 1.3,22 years, with a mean of 11.2 ± 4.9 years. History of blood transfusion was found in 81 children (77%). HCV RNA was detected in 58.1% of 74 children. Persistently elevated alanine aminotransferase (ALT) levels were present in 40 patients (54.1%). Hepatitis B virus markers (HBsAg and/or anti-HBc) were detected in 18 patients (24.3%). Twenty-six of the 43 HCV RNA-positive children underwent a diagnostic liver biopsy that showed chronic hepatitis in 19 patients (73.1%), cirrhosis in one case only (3.8%), and normal biopsy findings in seven children (26.9%). Blood transfusion remains a major risk of HCV transmission among Egyptian children. HCV infection is not always benign in the childhood period. ALT levels remain elevated in half of the children and histological abnormalities are detected in three quarters of HCV RNA-positive cases. [source]