Search results for "Hepatitis B Vaccines"
showing 10 items of 47 documents
N-terminal myristoylation-dependent masking of neutralizing epitopes in the preS1 attachment site of hepatitis B virus
2011
The N-terminally myristoylated preS1 domain of the large hepatitis B surface protein (LHBs) mediates specific attachment of hepatitis B virus (HBV) to hepatocytes. Its B-cell epitopes leading to neutralization of infectivity are not yet characterized.We inserted C- and N-terminal preS1 peptides into the most immunogenic region of HBV core particles, therewith immunized Balb/c mice and determined binding properties and neutralization potential of resulting antibodies in vitro.The particles with preS1 inserts were highly immunogenic and the corresponding anti-preS antibodies strongly bound to HBV particles from chronic carriers infected with different HBV genotypes A-F. However, antibodies bi…
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 …
Mosaic particles formed by wild-type hepatitis B virus core protein and its deletion variants consist of both homo- and heterodimers.
2003
AbstractCo-expression in Escherichia coli of wild-type (wt) hepatitis B virus core protein (HBc) and its naturally occurring variants with deletions at amino acid positions 77–93 or 86–93 leads to formation of mosaic particles, which consist of three dimer subunit compositions. These compositions are wt/variant HBc heterodimers and two types of homodimers, formed by wt HBc or the variant HBc themselves. Mosaic particles were found also when both HBc deletion variants 77–93 and 86–93 were co-expressed in E. coli. These findings are discussed in terms of their significance for hepatitis B virus pathogenesis and prospective use of mosaic particles in vaccine development.
Long-term pertussis-specific immunity after primary vaccination with a combined diphtheria, tetanus, tricomponent acellular pertussis, and hepatitis …
2001
ABSTRACT The aim of this study was to compare pertussis-specific humoral and cellular immunity in children 5 years after a primary vaccination with a combined diphtheria, tetanus, tricomponent acellular pertussis, and hepatitis B vaccine (DTaP-HBV; InfanrixHepB; SmithKline Beecham) with immunity after natural infection. The subjects were 38 children aged 5 to 6 years who received DTaP-HBV at 3, 5, and 11 months of life and 21 subjects of similar ages and sex who acquired pertussis in the first year of life. Immunoglobulin G (IgG) antibody titers against Bordetella pertussis antigens, peripheral blood mononuclear cell-specific proliferation, and the secretion of cytokines were evaluated. Aft…
Long-term pertussis-specific immune responses to a combined diphtheria, tetanus, tricomponent acellular pertussis and hepatitis B vaccine in pre-term…
2002
Abstract Immunoglobulin G (IgG) antibody titres against pertussis antigens, Bordetella pertussis-specific proliferation and cytokine production by peripheral blood mononuclear cells (PBMCs) were evaluated at the age of 5–6 years in 13 children who had been pre-term infants with a gestational age (GA) of ≤31 weeks, 10 who had been pre-term infants with a GA of 32–37 weeks, and 15 who had been term infants with a GA of 38–42 weeks. All of the infants had been immunised with a combined diphtheria, tetanus, tricomponent acellular pertussis and hepatitis B vaccine (DTaP–HBV) at 3, 5, and 11 months of post-natal age. Our results show that the long-term immune responses induced by primary pertussi…
The effect of granulocyte-macrophage colony-stimulating factor (GM-CSF) on hepatitis B vaccination in haemodialysis patients.
1996
Haemodialysis patients often fail to respond to hepatitis B vaccination. In this pilot study, 15 patients previously non-responsive to at least three 40 micrograms doses of hepatitis B vaccine were given 0.5, 5 or 10 micrograms kg-1 granulocyte-macrophage colony-stimulating factor (GM-CSF) subcutaneously 24 h prior to booster vaccination with a hepatitis B vaccine. Seven of the 15 patients developed antibody to hepatitis B surface antigen (HBsAb) (35-7240 IU L-1) upon initial vaccination with GM-CSF and two of four individuals responded with low HBsAb titres of 15 and 60 IU L-1 when revaccinated with hepatitis B surface antigen (HBsAg) and twice the dose of GM-CSF. The application of GM-CSF…
Safety, reactogenicity and immunogenicity of a combined hexavalent tetanus, diphtheria, acellular pertussis, hepatitis B, inactivated poliovirus vacc…
2003
Safety, reactogenicity and immunogenicity of GSK Biologicals` hexavalent DTPa-HBV-IPV/Hib vaccine (Infanrix(R)hexa) was assessed when used for primary vaccination at 3, 4 and 5 months of age (N = 2163), compared to the separate administration of DTPa-IPV/Hib and HBV vaccines (N = 720). A similar safety and reactogenicity profile was demonstrated for both vaccine regimens, as well as a good immune response for all antigen components. By offering protection against six diseases in it series of single injections, the hexavalent DTPa-HBV-IPV/Hib vaccine was shown to be a safe, well tolerated and immunogenic alternative to primary immunization with licensed separately administered vaccines. (C) …
Active hepatitis B vaccination of dialysis patients and medical staff
1984
AbstractActive hepatitis B vaccination of dialysis patients and medical staff. One hundred six patients with terminal renal insufficiency and 29 medical personnel were given three doses of hepatitis B vaccine at an interval of 0, 1, and 6 months (Merck, Sharp and Dohme, West Point, Pennsylvania, part of a joint study no. 649). Chronic hemodialysis patients (N = 99) received 40 µg vaccine (V) i.m. Uremic patients, who were just about to start chronic dialysis treatment (N = 7), were given 40 µg V, and at the first vaccination 3ml hyperimmune globulin (HBIG) in addition. The medical personnel was alternately vaccinated with 20 µg V (N = 8), 40 µg (N = 11), 40 µg V, and 3ml HBIG at the first v…
Two versus three doses of a meningococcal C conjugate vaccine concomitantly administered with a hexavalent DTaP-IPV-HBV/Hib vaccine in healthy infant…
2007
The immunogenicity and reactogenicity of a meningococcal serogroup C (MenC) conjugate vaccine given concomitantly with DTaP-IPV-HBV/Hib vaccine according to a two- or three-dose schedule in healthy infants was evaluated. At 1 month post-vaccination, 98% (two doses) and 100% (three doses) of subjects had serum bactericidal antibody using human complement assay (hSBA) titres > or =1:8; at 12 months of age > or =89% of subjects in each group remained seroprotected. Induction of immunological memory, as evaluated by administration of a meningococcal serogroup A/C polysaccharide vaccine challenge dose, was similar for both regimens and no interference was observed in the immune response to MenC …
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…