Search results for "HEPATITIS B"

Occult Hepatitis B and Infliximab-induced HBV Reactivation

2007

Three-dimensional structure of hepatitis B virus core particles determined by electron cryomicroscopy

1994

Human hepatitis B virus core protein expressed in E. coli assembles into two sizes of particle. We have determined their three-dimensional structures by electron cryomicroscopy and image processing. The large and small particles correspond to triangulation number T = 4 and T = 3 dimer clustered packings, containing 240 and 180 protein subunits, respectively. The local packing of subunits is very similar in the two sizes of particle and shows holes or channels through the shell. The native viral core particle packages RNA and is active in reverse transcription to DNA. The holes we observe may provide access for the necessary small molecules. Shells assembled from the intact core protein cont…

Low frequency of cytotoxic liver-infiltrating T lymphocytes specific for endogenous processed surface and core proteins in chronic hepatitis B.

1993

To investigate the role of hepatitis B virus (HBV)-specific CD8+ T cells in chronic hepatitis B, the lytic activity of peripheral blood mononuclear cells (PBMC) and liver-infiltrating T cell clones and cytotoxic T cell (CTL) lines stimulated by recombinant vaccinia virus-infected cells were analyzed. Autologous and allogeneic Epstein-Barr virus-transformed B cells infected with vaccinia vectors (VAC) that contain sequences of the surface (S), secretory core (E), cytoplasmatic core (C) VAC antigen of HBV, or the wild-type (WT) VAC served as target cells. ELISA and immunoblotting showed HBV antigen expression in infected cells. Neither PBMC nor C- or E-VAC-stimulated CTL lines showed specific…

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…

H-2(d) mice born to and reared by HBeAg-transgenic mothers do not develop T cell tolerance toward the hepatitis B virus core gene products.

2000

The function of the secretory core gene product (HBeAg) of the human hepatitis B virus (HBV) is unknown. It has been proposed that this protein may be passed from the mother to her offspring at the perinatal stage where it might induce immune tolerance. In a previous study we have shown that the murine placenta presents an efficient barrier for the HBe protein and that H-2(b) mice born to HBeAg-positive transgenic mothers do not develop tolerance of specific cytotoxic T cells. In the present work we demonstrate that transgenic mice expressing high serum levels of HBeAg secrete only small amounts of this protein into their milk and excrete minute amounts of the viral gene product in their ur…

Association of hepatitis Be antigen (HBeAg) with the core of the hepatitis B virus (HBcAg).

2008

— Three substances (pronase E, sodium dodecylsulfate (SDS) and guanidine hydrochloride) with different chemical actions partially convert HBcAg to HBeAg. This process retains the integrity of the HBcAg particle, which was not different between HBcAg subpopulations, and does not generate HBcAg or HBeAg sub-units. DNA polymerase activity was destroyed by SDS and guanidine hydrochloride, but not by pronase E. Serum HBeAg could not be converted into HBcAg, suggesting that this might be an irreversible process. The data are consistent with the assumption that HBcAg and HBeAg are coded for by the same gene (C gene of the HBV-DNA).

Demonstration and partial characterization of an intermediate HBcAG (Dane particle) population.

1981

Abstract Hepatitis-B core antigen (HBcAg) was released from Dane particles previously separated from anti-HBc by repeated pelleting through sucrose gradients separated into three HBcAg populations when analysed by cesium chloride density gradient centrifugation. Heavy HBcAg particles banded at a density of 1.355 gm/ml, intermediate HBcAg particles at a density of 1.33 gm/ml, and light mediate HBcAg particles at a density of 1.30 gm/ml. Like heavy HBcAg particles, intermediate HBcAg particles contained DNA polymerase activity, but the ratio of HBcAg to DNA polymerase activity was significantly different in both populations. Intermediate HBcAg particles could not be separated from heavy HBcAg…

Interferon-alpha 2a increases serum concentration of hyaluronic acid and type III procollagen aminoterminal propeptide in patients with chronic hepat…

1994

Interferon-alpha (IFN-alpha) has become an important drug for the treatment of chronic viral liver diseases. However, the action of IFN-alpha remains unclear. We investigated whether human recombinant IFN-alpha modulates serum concentrations of hyaluronic acid (HA) and type III procollagen aminoterminal propeptide (P-III-NP) in 56 patients with chronic hepatitis-B under IFN-alpha therapy. IFN-alpha increased the HA serum level in 44 of 46 patients and, after cessation of treatment, HA serum levels returned to the pretherapy levels. The increase of HA serum level was higher in patients with active cirrhosis (aC) than in patients with chronic persistent hepatitis (CPH) and in patients with se…

Spread of hepatitis B virus infection among family contacts of asymptomatic HBsAg carriers

1979

Family members of 34 asymptomatic HBsAg carriers were tested for different hepatitis B virus (HBV) markers. Among 67 family members tested 24 (36%) presented signs of a past or ongoing HBV-infection. Spread of HBV-infection was particularly high in those families in which the HBsAg carrier was positive for HBeAg and Dane particle-associated DNA polymerase activity. Non-parenteral “horizontal” transmission of HBV among spouses and brothers and sisters and probably parenteral vertical transmission of HBV from carrier mothers to their infants occurred in approximately the same frequency. Fathers transmitted HBV unfrequently to their offsprings. The results show that the risk to acquire a HBV-i…

Occurrence of hepatocellular carcinoma and decompensation in western european patients with cirrhosis type B

1995

To examine the morbidity of compensated cirrhosis type B, a cohort of 349 Western European, white patients (86% men; mean age, 44 years) with biopsy-proven cirrhosis was followed up for a mean period of 73 months and was studied for occurrence of hepatocellular carcinoma (HCC) and decompensation. At entry into the study all patients were tested for hepatitis B e antigen (HBeAg; 34% of patients were HBeAg-positive) and antibody to hepatitis delta virus (anti-HDV; 20% of patients were anti-HDV-positive); 48% of 252 patients tested were hepatitis B virus (HBV)-DNA-positive. During follow-up HCC developed in 32 (9%) of the 349 patients and decompensation was observed in 88 (28%) of 317 tumor-fr…