Search results for "CAG"
showing 10 items of 492 documents
Hepatīta B serdes antigēna vīrusveidīgajās daļiņās spontāni iepakoto RNS noteikšana un raksturošana dažādu E. coli producentu celmos
2018
Šajā darbā tika analizētas E. coli producētu HBcAg VVD iepakotās RNS atkarībā no izvēlētās HBcAg ekspresijas plazmīdas un to monomēru vai dimēru formas, izvēlētājiem E. coli celmiem un kultivēšanas barotnes. Pavisam tika analizētas 12 dažādas šo parametru kombinācijas. Tika apskatīti gan kultūru augšanas parametri (kultūru optiskais blīvums un īpatnējā HBcAg produkcija), gan arī analizēta VVD pakotā RNS pēc tās fragmentu garuma un kvalitatīvā sastāva. Trim eksperimenta variantiem arī tika veikta NGS datu analīze. Eksperimenta rezultāti parāda, ka visiem 12 eksperimenta variantiem kvantitatīvi un kvalitatīvi atšķirās VVD iepakotā RNS, bet, lai iegūtu pilnīgāku priekštatu par pakošanas atšķir…
Relationship of pre-S encoded antigens in liver and clinical manifestations of chronic hepatitis B infection.
2008
Pre-S1 and pre-S2 encoded antigens of hepatitis B virus were localized in liver tissue using monoclonal antibodies. They were found to be exclusively expressed in the cytoplasm of liver cells. Cell bound pre-S1 encoded protein was often detected in patients with chronic liver disease and viremia. Only a small number of the HBsAg positive cells also contained pre-S1 antigen. There was no correlation with nuclear HBcAg. Livers of non-viremic HBsAg carriers contained many HBsAg expressing liver cells, that were frequently also positive for pre-S2 encoded protein but contained no detectable pre-S1 encoded protein at all. It remains open whether cell bound pre-S2 containing proteins of middle si…
HBV-specific immune defect in chronic hepatitis B (CHB) is correlated with a dysregulation of pro- and anti-inflammatory cytokines.
1999
SUMMARY The aim of this study was to examine the immunomodulating effects of rhIL-12 on the immune response induced by hepatitis B virus (HBV) antigens in clinical subgroups of patients with HBV infection. Peripheral blood mononuclear cells (PBMC) of 80 patients were stimulated with HBsAg, HBcAg, pre-S1Ag and tetanus toxoid in the absence or presence of IL-12 (0.01, 0.1 and 1 ng/ml). Stimulation by anti-CD3 + anti-CD28 and lipopolysaccharide (LPS) were used as controls. Proliferation and cytokine production were determined by 3H-thymidine uptake and ELISA after 72 h. After stimulation with HBV antigens only, production of tumour necrosis factor-alpha (TNF-α) or IL-10 was observed in all pat…
Immunohistochemical Characterization of 130 Cases of Primary Hepatic Carcinomas
1987
Primary liver carcinoma (PLC) may express a certain number of markers. Here we communicate results of an analysis of five such markers (alpha-1-antitrypsin--AAT--, carcino-embryonic antigen --CEA--, alpha-fetoprotein --AFP--, and superficial --HBsAg-- and core --HBcAg-- antigens of hepatitis B virus) by means of PAP techniques in 130 cases of PLC, comparing the neoplastic tissue and the non-tumorous liver. Three variants of PLC are distinguished: hepatocarcinoma (HC) (108 cases); cholangiocarcinoma (CC) (19 cases); and three cases of hepatocholangiocarcinoma (HCC). AAT was positive in 29 HC, 2 HCC, and negative in all 19 CC. CEA appeared positive in 16 HC, 16 CC and only one HCC. AFP was po…
The diagnostic significance of intrahepatocellular hepatitis-B-surface-antigen (HB s Ag), hepatitis-B-core-antigen (HB c Ag) and IgG for the classifi…
1975
Liver biopsies of patients with inflammatory liver diseases and clinically healthy HBsAg-carriers were examined for presence of intracellular HBsAg, HBcAg and IgG by direct immunofluorescence. The studies revealed the following results: 1. In most cases healthy HBsAg-carriers had HBsAg in the cytoplasm, but they did never show HBcAg in the nuclei of hepatocytes. 2. In the early phase some patients with HBsAg-positive acute hepatitis had HBcAg and/or HBsAg in their hepatocytes. In a normal course with complete recovery the immunoelimination may clear either phenomenon at variable stages of the disease. 3. Cases one year after complete recovery of acute virus B-hepatitis had no HB-components …
IgM-Antikörper gegen Hepatitis B core-Antigen (anti-HBc IgM) bei “gesunden” HBsAg-Trägern. Eine Verlaufsstudie bei 75 Fällen
1981
In 75 healthy HBsAg carriers with normal liver tissue who were followed over a four years period, anti-HBc IgM was determined by ELISA. 61 HBsAg carriers (81%) were positive for anti-HBc IgM at first investigation. 54 individuals demonstrated persistence of anti-HBc IgM, 7 became anti-HBc IgM-negative within the observation period. 12 persons were persistent anti-HBc IgM-negative, and 2 developed anti-HBc IgM of low quantities. 3 of 4 individuals with HBsAg clearance demonstrated a considerable decrease of anti-HBc IgM concentration. Although signs of liver damage or development of chronic liver diseases were not observed at the time of control biopsy the existence of anti-HBcIgM indicates …
Analysis of the precore DNA sequence and detection of precore antigen in liver specimens from patients with anti-hepatitis b e—positive chronic hepat…
1995
A number of naturally occurring hepatitis B virus (HBV) mutants unable to synthesize the hepatitis B e antigen (HBeAg) have been identified in patients characterized by HBV DNA and anti-HBe in their serum. Because the analysis of the HBV-associated DNA and antigens in the liver tissue is still not complete, we investigated the precore sequence of HBV DNA and its encoded proteins in the liver tissue of 32 patients positive for HBV DNA and anti-HBe in their serum. Three different groups of patients were identified. Group I (n = 14) was characterized by viral DNA sequences with a G-A transition in the distal precore gene region, thus creating a termination codon (TAG). Liver tissue from this g…
Mixed cryoglobulinemia type II in chronic hepatitis B associated with HBe-minus HBV mutant: Cellular immune reactions and response to interferon trea…
1994
The case of a young female patient with chronic active hepatitis B, vasculitic purpura, edema, and circulating immune complexes due to mixed Cryoglobulinemia is described. Serum transami-nases were elevated. Serological assays showed hepatitis B surface antigen (HBsAg), antibody to hepatitis B e antigen (anti-HBe), and antibody to hepatitis B core antigen (anti-HBc) antibodies but no antibody to hepatitis C virus (anti-HCV) or antibody to hepatitis delta virus (anti-HDV) antibodies. Using hepatitis B virus-polymerase chain reaction (HBV-PCR) and direct sequencing a precore/core (preC/C) mutant unable to synthesize HBeAg was detected in serum. HBV antigens were demonstrated in the circulatin…
The presence of high amounts of HBV-DNA in serum is associated with suppressed costimulatory effects of interleukin 12 on HBV-induced immune response
1999
Abstract Background/Aims: The aim of this study was to examine the influence of the viral load on costimulatory effects of rhIL-12 on the hepatitis B virus (HBV)-induced immune response. Methods: Peripheral blood mononuclear cells of HBsAg positive patients without cirrhosis were stimulated with HBsAg, HBcAg, preSlAg and tetanus toxoid in the absence or presence of IL-12 (0.01, 0.1 and 1 ng/ml). Stimulation by α-CD3+α-CD28, pokeweed mitogen (PWM) and lipopolysaccharide (LPS) were used as controls. Then, proliferation and cytokine production were determined by 3 H-thymidine uptake and ELISA after 72 h. The patients were divided into group 1 ( n =21): HBV-DNA: not detectable, group 2 ( n =13)…
Priming of cytotoxic T cell responses to exogenous hepatitis B virus core antigen is B cell dependent
2003
The hepatitis B virus (HBV) core antigen (HBcAg) has a unique ability to bind a high frequency of naive human and murine B cells. The role of HBcAg-binding naive B cells in the immunogenicity of HBcAg is not clear. The HBcAg-binding properties of naive B cells were characterized using HBcAg particles with mutated spike region (residues 76-85) sequences. Deletion of residues 76-85 (HBcDelta76-85) destroyed naive B cell binding, whereas deletion of residues 79-85 did not. HBcAg particles with an Ile instead of the natural Ala at position 80 did not bind naive B cells, whereas reversion of Ile80--Ala restored B cell binding. Destroying the B cell-binding ability of HBcAg had a marginal effect …