Search results for "HBc"
showing 10 items of 44 documents
Hepatīta B vīrusa morfoģenēzes pētījumi, izmantojot alfavīrusu ekspresijas sistēmu
2015
Darba mērķis bija pētīt hepatīta B vīrusa (HBV) kapsīda, subvirālo daļiņu un virionu izveides nosacījumus, izmantojot alfavīrusa ekspresijas sistēmu. Inficēto BHK-21 šūnu preparātu analīze tika veikta ar ELISA, imunoblotu un imunocitoķīmiju. Tika veiksmīgi izveidoti rekombinanti SFV1-HBV vīrusi – PG – pilna genoma HBV vīruss un HBC – vīruss, ko veido kapsīda proteīni, kā arī pārbaudīti laboratorijas kolekcijā esošais saīsināta kapsīda proteīna ΔC vīruss, un apvalka proteīna 1/L vīruss. Veicot BHK-21 šūnu infekciju ar 1/L vīrusu kombinācijā ar HBC, PG vai ΔC vīrusiem, bija jāņem vērā alfavīrusu konkurence. Tika novēroti dažāda brieduma kapsīdi ar atšķirīgu nukleīnskābju saturu ko raksturo at…
Smouldering hepatitis B virus replication in patients with chronic liver disease and hepatitis delta virus superinfection
1991
Hepatitis B virus deoxyribonucleic acid (HBV-DNA) was studied by Southern blot analysis in liver biopsy specimens from 75 HBsAg-positive patients with chronic liver disease living in southern Italy. Twenty-seven of the patients were hepatitis delta virus (HDV) superinfected. Intrahepatic HBV-DNA was detected in 54 (72%) patients, 32 (59%) of them with replicative forms. The presence of replicative forms was directly related to liver HBcAg and inversely related to liver HDAg, as shown by multivariate analysis. However, 14 patients with intrahepatic HBV-DNA non-replicative pattern and about half of HDV-infected patients were liver HBcAg and/or serum HBV-DNA positive, mostly in low amounts. Hi…
Can the serological status of anti-HBc alone be considered a sentinel marker for detection of occult HBV infection?
2008
Some individuals have “occult” infection with hepatitis B virus (HBV), defined as presence of HBV genome in the serum or liver tissue without HBV surface antigen (HBsAg) in the serum. The aim of this study was to investigate whether serum antibodies against HBV core antigen in isolation (“anti-HBc alone”) are a useful marker of “occult” HBV in patients with or without hepatitis C virus (HCV) infection. “Anti-HBc alone” was detected in the sera of 119/6,544 (1.8%) asymptomatic outpatients referred to the diagnostic laboratory for routine testing for viral hepatitis, 62/607 (10.2%) drug users, and 42/195 (21.5%) patients with hepatocellular carcinoma. Using three in-house nested-PCR amplifica…
Hepatitis B defective virus with rearrangements in the preS gene during chronic HBV infection.
1991
We have found a defective form of HBV2 in a HBsAg- and anti-HBe-positive patient with liver cancer. Viral deletions were identified in the preS coding region using PCR. The presence of deleted HBV forms was observed in serum, PBMC, and liver samples. After sequencing 12 clones were analyzed (subtype adr). In 9 out of 12 clones a 183-bp in-frame deletion was recorded in the preS1 region (2995 to 3177). Three out of 9 clones also yielded rearrangements of the preS2 N-terminal part. Four out of 9 showed numerous point mutations in the preS1 and preS2 sequence. In addition, 3 out of 12 clones, which did not show the 183-bp preS1 deletion were found to have small deletions and insertions in the …
Occult hepatitis B virus in liver tissue of individuals without hepatic disease
2008
Abstract BACKGROUND/AIMS: While many data are available concerning occult hepatitis B virus (HBV) infection in patients with hepatic disorders, there is little information about this cryptic infection in individuals without liver disease. The aim of this study was to investigate the prevalence of occult HBV in the general population by examining liver specimens from a large series of HBV-surface-antigen negative individuals with no clinical and biochemical evidence of liver disease. METHODS: The presence of HBV DNA was evaluated by testing, through polymerase chain reaction techniques, DNA extracts from 98 liver-disease-free individuals who underwent liver resection or needle biopsy during …
HBV kapsīdu savākšanās inhibīcija ar mazmolekulāriem savienojumiem
2016
Hepatīta B vīrusa (HBV) infekcija hroniskā formā ir viena no bīstamākajām mūsdienu saslimšanām, tāpēc aktīvi tiek meklētas iedarbīgas zāles infekcijas ārstēšanai. Ar mērķi atrast efektīvu un netoksisku HBV nukleokapsīdu inhibitoru, ir veikta plaši pētīta Bay-41-4109 inhibitora un tā analogu pārbaude zīdītāju šūnās. Šajā darbā HBV kapsīdas proteīna (HBc) sintēze BHK-21 šūnās nodrošināta, izmantojot rekombinantu alfavīrusa replikonu. Ir pārbaudīta Bay-41-4109 un tā analogu citotoksicitāte šūnās. Izmantojot natīvās agarozes un SDS-PAA gēla elektroforēzes un imunoblota metodes tika salīdzināta inhibitoru ietekme uz HBc proteīna ekspresiju un nukleokapsīdu veidošanos šūnās. Atrasts, ka viens no …
Proliferative response of CD4+ T cells and hepatitis B virus clearance in chronic hepatitis with or without hepatitis B e-minus hepatitis B virus mut…
1995
To assess the significance of cell-mediated immunity, T cells were derived from the peripheral blood and liver tissue of hepatitis B virus (HBV)-infected patients and controls. The analysis of the 3H-thymidine-uptake in response to a panel of recombinant HBV antigens revealed that peripheral blood mononuclear cells (PBMC) of the 25 viremic patients with inflammatory active, chronic hepatitis B, 16 with wild-type and nine with HBe-minus HBV mutant infection, showed stronger proliferative responses to HBc and HBe antigens than 16 asymptomatic nonviremic HBsAg carriers with normal aminotransferase levels (HBc: SI 19.3 +/- 3.9 vs. 13.0 +/- 3.2 vs. 8.0 +/- 1.2; P.01 and HBe: SI 16.6 +/- 4.0 vs. …
Molecular Basis for the Interaction of the Hepatitis B Virus Core Antigen with the Surface Immunoglobulin Receptor on Naive B Cells
2001
ABSTRACTThe nucleocapsid of the hepatitis B virus (HBV) is composed of 180 to 240 copies of the HBV core (HBc) protein. HBc antigen (HBcAg) capsids are extremely immunogenic and can activate naive B cells by cross-linking their surface receptors. The molecular basis for the interaction between HBcAg and naive B cells is not known. The functionality of this activation was evidenced in that low concentrations of HBcAg, but not the nonparticulate homologue HBV envelope antigen (HBeAg), could prime naive B cells to produce anti-HBc in vitro with splenocytes from HBcAg- and HBeAg-specific T-cell receptor transgenic mice. The frequency of these HBcAg-binding B cells was estimated by both hybridom…
Highly specific auto-antibodies against claudin-18 isoform 2 induced by a chimeric HBcAg virus-like particle vaccine kill tumor cells and inhibit the…
2011
Abstract Strategies for antibody-mediated cancer immunotherapy, such as active immunization with virus-like particle (VLP)-based vaccines, are gaining increasing attention. We developed chimeric hepatitis B virus core antigen (HBcAg)-VLPs that display a surface epitope of the highly selective tumor-associated cell lineage marker claudin-18 isoform 2 (CLDN18.2) flanked by a mobility-increasing linker. Auto-antibodies elicited by immunization with these chimeric HBcAg-VLPs in 2 relevant species (mouse and rabbit) bind with high precision to native CLDN18.2 at physiologic densities on the surface of living cells but not to the corresponding epitope of the CLDN18.1 splice variant that differs b…
Cellular cytotoxicity against autologous hepatocytes in children with different forms of chronic hepatitis B.
1990
Cell-mediated immune reactions play the most important role in the pathogenesis of chronic viral and auto-immune hepatitis. Cellular cytotoxicity (CC) of peripheral blood lymphocytes against autologous hepatocytes isolated from liver biopsies was studied in 29 children with different types of hepatitis B surface antigen (HBsAg)-positive hepatitis. Children with chronic hepatitis B showed higher cytotoxicity than control patients. However, a correlation of cytotoxicity to serum amino-transferases, HBeAg-/Anti-HBe-status, and hepatitis B virus DNA in serum could not be found. Children with a higher percentage of hepatitis B core antigen (HBcAg) expression in their liver tissue presented lower…