Search results for "Hepatitis B Surface Antigens"
showing 10 items of 102 documents
One‐quarter of chronic hepatitis D patients reach HDV‐RNA decline or undetectability during the natural course of the disease
2021
BACKGROUND Spontaneous HDV-RNA fluctuations, assessed by nonstandardised in-house assays, have been reported during the course of chronic hepatitis delta (CHD). AIMS To evaluate changes in serum HDV-RNA concentrations in untreated CHD patients and correlate these changes with other HBV markers. METHODS A total of 323 consecutive serum samples from 56 CHD patients (detectable HDV-RNA) followed for >3 years were retested for HDV-RNA levels by a sensitive technique using the first WHO international HDV-RNA standard. Quantitative HBsAg, HBV-DNA, and HBV-RNA were also determined. RESULTS Most participants were male, middle-aged, white European, and HBeAg-negative (82%). Almost half had liver cir…
Baseline sero-epidemiology of hepatitis B virus infection in children and teenagers in Italy. A survey before mass hepatitis B vaccination
1991
During the period May 1987 to November 1989, the prevalence of hepatitis B virus (HBV) markers was determined by ELISA in serum samples of 7405 (55% male, 45% female) apparently healthy persons 3-19 years of age in Italy. Earlier studies of adults there had shown an intermediate degree of HBV endemicity (hepatitis B surface antigen carrier rate greater than 2%). Persons were selected by systematic cluster sampling in five different geographical areas of Italy. The overall prevalence of hepatitis B surface antigen (HBsAg) was 0.6%. The overall prevalence of at least one marker of HBV was 2.8%; it increased from 1.7% among children 3-5 years of age to 4.5% in teenagers 17-19 years of age (P l…
Hepatitis B virus infection in native versus immigrant or adopted children in Italy following the compulsory vaccination.
2001
Background: Compulsory vaccination of children against hepatitis B virus (HBV) infection was introduced in Italy in 1991. Patients and Methods: To evaluate the current importance of pediatric HBV infection, we studied 359 HBsAg-positive children admitted to 16 centers in Italy from 1991 to 1998. 185 patients were natives of Italy and 174 (39 immigrants and 135 adopted) came from highly endemic countries (eastern Europe: 60.9%, Asia: 16.7%, Africa: 14.9% and Central and South America: 5.7%). Results: Transaminase levels were moderately altered in both Italian (mean 134 UI/l) and foreign children (mean 168 UI/l). In total, 77% of Italian children and 88% of foreign children tested HBeAg posit…
Hepatitis B virus reactivation and alemtuzumab therapy
2005
Reactivation of hepatitis B virus infection in subjects receiving cytotoxic treatment for heamatological malignancies occurs in 21–53% of chronic HBsAg carriers and in an unknown number of HBsAg negative subjects harbouring occult HBV infection. Immmunotherapy with alemtuzumab, a humanized monoclonal antibody against CD52 epitopes on lymphocytes cells produces deep immunosuppression. We describe two subjects with chronic lymphocytic leukaemia and occult HBV infection who developed a virological and biochemical flare of hepatitis B following immunotherapy with alemtuzumab. One of them developed full blown hepatitis with seroreversion from anti-HBs to HBsAg after four weeks of alemtuzumab the…
Antibody persistence and immune memory elicited by combined hepatitis A and B vaccination in older adults.
2007
Response to hepatitis A and B vaccines has been reported to decline with age. This open, prospective, single-site study examined the long-term response to the combined hepatitis A/B vaccine Twinrix in 98 primary responders aged 45-67 years. Levels of antibody against hepatitis A virus (HAV) and hepatitis B surface antigen (HBs) were tested 30 months after initial vaccination. At this stage, all participants remained seropositive for anti-HAV and 70% for anti-HBs. A booster vaccination was offered to those who had responded to the first vaccination but then lost protective levels of anti-HBs. An anamnestic response was observed in all cases.
Serologic control against hepatitis B virus among dental students of the University of Granada, Spain
2015
Background: To evaluate the immunological situation against hepatitis B virus (HBV) of a cohort of dentistry students, to analyze the behavior of the levels of hepatitis B surface antigen (anti-HBs) after the administration of one or three vaccine doses, and to determine the influence of age and sex on the immune response. Material and Methods: This retrospective cohort study included students attending the School of Dentistry of the institution where the study was performed from 2005 to 2012 who had completed the public health vaccination calendar for HBV at the age of 12-13. Data on age, sex, basal anti-HBs levels, post-vaccination anti-HBs results and final anti-HBs levels were collected…
Hepatocellular carcinoma after thorotrast exposure: establishment of a new cell line (Mz-Hep-1).
1985
A human hepatoma cell line, associated with thorotrast exposure, from an hepatitis B marker-negative patient was established as a permanent cell line (Mz-Hep-1) in tissue culture. Histology of the primary tumor, as well as phase contrast, transmission and scanning electron microscopy of the cultured cells showed typical characteristics of liver cells. Mz-Hep-1 cells secreted complement components (C2, C3, C4), carcinoembryonic antigen, lactate dehydrogenase, chymotrypsin, haptoglobin and retinol-binding protein and expressed HLA-, transferrin-, blood group B-related determinants and complement component C5 and carcinoembryonic antigen on their cell surface. Mz-Hep-1 cells represent the firs…
Reduced virus specific T helper cell induction by autologous dendritic cells in patients with chronic hepatitis B-restoration by exogenous interleuki…
2002
SUMMARYInsufficient stimulatory capacities of autologous dendritic cells (DC) may contribute in part to impaired T cell stimulation and therefore viral persistence in patients with chronic hepatitis B virus (HBV) infection. In order to characterize the antigen presenting functions of DC from chronic HBV carriers and controls antigen specific T cell responses were analysed. CD34+ peripheral blood progenitor cells were differentiated to immature DC in the presence of GM-CSF, IL-6/IL-6R fusion protein and stem cell factor. Proliferative CD4+ T cell responses and specific cytokine release were analysed in co-cultures of DC pulsed with HBV surface and core antigens or tetanus toxoid and autologo…
Properties of modified hepatitis B virus surface antigen particles carrying preS epitopes
1995
The current hepatitis B virus (HBV) vaccines contain the small (S) and middle (M) viral envelope proteins in particulate form but lack the large (L) protein. Although these particles elicit protective immunity to HBV, inclusion of the immunogenic preS1 region of the L protein may enhance their efficacy. To present preS1-derived epitopes on secretable subviral particles we rearranged the HBV envelope ORF by fusing part or all of the preS1 region to either the N or C terminus of the S protein. Fusion of the first 42 residues of preS1 to either site allowed efficient secretion of the modified particles and rendered the linked sequence accessible at the surface of the particle. Conversely, fusi…
Intracellular accumulation of incompletely processed transforming growth factor-alpha polypeptides in ground glass hepatocytes of chronic hepatitis B…
1996
Abstract Background: Transforming growth factor-alpha is an intracellularly processed and secreted polypeptide that induces a proliferative response in epithelial target cells and represents a potential regulatory factor in embryonic development, liver regeneration, and also hepatocarcinogenesis. We have observed focal transforming growth factor-alpha expression in liver tissues with chronic hepatitis B virus infection. Methods: To further elucidate the nature of this focal transforming growth factor-alpha accumulation were have analyzed overall 23 different liver tissues with chronic hepatitis B virus and hepatitis C virus infection as well as normal liver tissues by immunohistology, ELISA…