Search results for "HBcAg"
showing 10 items of 32 documents
Liver diseases and hepatitis B virus antigens and antibodies in chronic HBsAg carriers in childhood
1980
Liver biopsies were obtained from 109 children who had been chronic carriers of HBsAg for more than 6 months. The specimens were examined for the presen Ice of intracellular HBsAg, HBcAg and HBeAg by direct immunofluorescence. Sera were tested for HBeAg, virus B specific DNA polymerase, anti-HBs, anti-HBe and anti-HBc. On the basis of accepted histological criteria we found chronic active hepatitis (CAH) in 56 and chronic persistent hepatitis (CPH) in 19 children. 15 cases had minimal changes (minimal hepatitis, MH) and 19 normal liver tissue (healthy HBsAg carriers, HC). Children with CAH and CPH had HBeAg, DNA polymerase and anti-HBc in their serum. HBcAg and HBeAg were found in 5-50% of …
Prevalence of antibodies to hepatitis C virus among patients with cryptogenic chronic hepatitis and cirrhosis
1992
Many cases of chronic hepatitis and cirrhosis cannot be attributed to a known cause and are collectively referred to as cryptogenic chronic liver disease. We have evaluated the role of the hepatitis C virus in the pathogenesis of this condition in a retrospective serum analysis for antibody to hepatitis C virus in 129 patients with cryptogenic liver disease. Other causes of chronic hepatitis and cirrhosis were ruled out by clinical, serum biochemical and serological techniques. All 129 patients were HBsAg negative, but 28 (22%) had antibody to HBcAg. Sera were tested by radioimmunoassays using recombinant peptides for antibodies to nonstructural (C 100-3 and C33c) and structural regions (C2…
Ultrastructural localization of interferon-producing cells in the livers of patients with chronic hepatitis B
1991
Cells expressing alpha- and gamma-interferon were localized in the liver tissue of patients with chronic hepatitis B by means of light and electron microscopy using monoclonal antibodies. Interferon-positive cells were regularly seen in the infiltrating mononuclear cells, and the number showed a good correlation with the degree of the necroinflammatory activity of the disease. In chronic persistent hepatitis and in normal livers, they were infrequent or virtually absent. alpha-Interferon was shown to be positive in lymphocytes, polymorphonuclear leukocytes and fibroblasts, Kupffer cells and, weakly, in the cytoplasm of a few hepatocytes in cases of active hepatitis, whereas gamma-interferon…
Recombinant virus-like particles as a carrier of B- and T-cell epitopes of hepatitis C virus (HCV)
2005
The major aim of the project was the development of virus-like particles (VLP) displaying B- and T-cell epitopes of hepatitis C virus (HCV) proteins. To this end, hepatitis B virus core (HBc) particles were used as a carrier of HCV epitopes. Fragments of HCV genes encoding core (aa 98) and NS3 (aa 155) proteins were fused to the 3' terminus of the truncated HBV core gene. All recombinant plasmids led to relatively high levels of expression of chimeric proteins in E. coli, which resulted in the formation of complete "mature" VLP. Chimeric HBc/HCV VLPs were purified by combination of gel filtration and sucrose gradient centrifugation, and used for immunogenicity studies in mice. All variants …
IN SITU HYBRIDIZATION FOR DETECTION OF HEPATITIS B VIRUS GENOMES IN LIVER TISSUE OF CHRONIC INFECTED CHILDREN
1990
Detection of hepatitis B virus (HBV)-DNA in the liver of chronic infected patients is presently the most sensitive marker of viral replication and infectivity. In situ hybridization (ISH) allows the direct visualization of HBV infected liver cells and distribution of the viral sequences. This study was done to establish ISH and correlate the findings with conventional markers for HBV infection. Methods. Liver biopsies of 50 patients (28 ♂, 22 ♀) aged 0.5-20 years (mean 10.3) with various histological diagnoses were tested by 1SH. The HBV-DNA probe was labeled by nick translation with 35S-CTP to a specific activity of 3-5×108 cpm/μg DNA. Results. HBV-DNA/mRNA could be demonstrated in 38 pati…
A molecular assembly system that renders antigens of choice highly repetitive for induction of protective B cell responses.
2002
Virus like particles (VLPs) are known to induce potent B cell responses in the absence of adjuvants. Moreover, epitope-specific antibody responses may be induced by VLPs that contain peptides inserted in their immunodominant regions. However, due to steric problems, the size of the peptides capable of being incorporated into VLPs while still permitting capsid assembly, is rather limited. While peptides genetically fused to either the N- or C-terminus of VLPs present fewer assembly problems, the immune responses obtained against such epitopes are often limited, most likely because the epitopes are not optimally exposed. In addition, such particles may be less stable in vivo. Here, we show th…
New chimaeric hepatitis B virus core particles carrying hantavirus (serotype Puumala) epitopes: immunogenicity and protection against virus challenge
1999
Virus-like particles generated by the heterologous expression of virus structural proteins are able to potentiate the immunogenicity of foreign epitopes presented on their surface. In recent years epitopes of various origin have been inserted into the core antigen of hepatitis B virus (HBV) allowing the formation of chimaeric HBV core particles. Chimaeric core particles carrying the 45 N-terminal amino acids of the Puumala hantavirus nucleocapsid protein induced protective immunity in bank voles, the natural host of this hantavirus. Particles applied in the absence of adjuvant are still immunogenic and partially protective in bank voles. Although a C-terminally truncated core antigen of HBV…
Phenotype and function of monocyte derived dendritic cells in chronic hepatitis B virus infection.
2004
The antiviral T cell failure of patients with chronic hepatitis B virus (HBV) infection was suggested to be caused by a T cell stimulation defect of dendritic cells (DC). To address this hypothesis, monocyte derived DC (MDDC) of patients with chronic or resolved acute HBV infection and healthy controls were studied phenotypically by FACS analyses and functionally by mixed lymphocyte reaction, ELISA, ELISpot and proliferation assays of MDDC cultures or co-cultures with an allogeneic HBc-specific Th cell clone. HBV infection of MDDC was studied by quantitative PCR. MDDC from HBV patients seemed to be infected by the HBV, showed a reduced surface expression of HLA DR and CD40 and exhibited a r…
Modification of the immune response against hepatitis B virus by the human immunodeficiency virus.
1989
Hepatitis B virus and the human immunodeficiency virus are similarly transmitted. Individuals with preexisting HIV infection have a higher chance to become HBsAg carriers than do anti-HIV negative persons. Cytotoxic T cells with specificity for HBcAg, that are under the control of HBcAg-specific helper T cells, are responsible for liver injury. There is good evidence that HIV infection lowers inflammatory activity, is associated with milder liver histology, high levels of viral replication and low seroconversion rates. In addition interferon alpha therapy is less effective in anti-HIV positive subjects. The immune response against HBsAg is helper T-cell dependent and vaccination against hep…
Hepatīta B kora antigēna veidoto vīrusveidīgo daļiņu modificēšana vakcīnu prototipa izstrādei
2017
DENV vakcīnu izveide balstās galvenokārt, izmantojot dzīvus novājinātus vīrusus. 2015. gadā tika reģistrēta pirmā tetravalenta novājināta denges vīrusa vakcīna. Kā drošāks vakcīnas veids ir subvienību vakcīnas. Daudzsološākais DENV antigēns subvienību vakcīnas izveidē ir apvalka proteīna III domēns. Lai palielinātu antigēna subvienības imunogenitāti, tiek izmantotas vīrusveidīgās daļiņas (VLP) kā svešu antigēnu nesēji. Tā kā VLP ir pašnereplicējošas, tās tiek uzskatītas par drošākiem kandidātiem vakcīnu izveidē, salīdzinot ar dzīviem novājinātiem vīrusiem. Maģistra darba mērķis bija iegūt 2. serotipa denges vīrusa apvalka III domēnu (DV2-III) prezentējošas mutantās HBc VLP. Pētījumā tika pā…