Induction of effective immune responses may help prevent cancer progression. Tumor-specific antigens, such as those of human papillomaviruses involved in cervical cancer, are targets with limited intrinsic immunogenicity. Here we show that immunization with low doses (10(6) infectious units/dose) of a recombinant human adenovirus type 5 encoding a fusion of the E7 oncoprotein of human papilloma...

We extend well-known mathematical models of viral infection to examine the response of cytotoxic T lymphocytes (CTL) to both conserved and variable viral epitopes. Because most viruses are subject to error-prone reproduction, CTL recognition may be faced with highly variable epitopes, while other CTL epitopes may remain conserved across viral strains. In this paper we examine the steady state c...

BACKGROUND Epitopes can be defined as the molecular structures bound by specific receptors, which are recognized during immune responses. The Immune Epitope Database and Analysis Resource (IEDB) project will catalog and organize information regarding antibody and T cell epitopes from infectious pathogens, experimental antigens and self-antigens, with a priority on NIAID Category A-C pathogens (...

Quantification of serum hepatitis B surface antigen (HBsAg) helps the management of patients with chronic hepatitis B virus (HBV) infection. Median HBsAg levels differ significantly during the natural history of HBV infection, progressively declining from immune tolerance to inactive phase. The combination of an HBsAg <1000 IU/mL and HBV DNA <2000 IU/mL at a single time point accurately identif...

Early vaccination is necessary to protect infants from various infectious diseases. However, this is often unsuccessful largely due to the immaturity of the neonatal immune system. Furthermore, maternally derived antibodies can interfere with active immunization. We have previously shown in young mice that immune responses against several different antigens can be improved by the addition of ol...

In this report we define the parameters of the human immune response after immunization with hepatitis B vaccine. 2 wk after booster immunization, there is significant spontaneous secretion of antibody to hepatitis B surface antigen (anti-HBs IgG), which is not further augmented by stimulation with antigen or pokeweed mitogen (PWM). By 4 wk there is little spontaneous secretion of specific anti...

HBs protein is encoded by the pre-S and S genome, and the detection of HBs antigen (HBsAg) in sera is an initial step for the diagnosis of hepatitis B virus (HBV) infection. The “a” determinant region (amino acid residues 124–147) is the main epitope for inducing a protective immune response. Mutations in the “a” determinant region, known as escape mutants, affect antigenicity and hinder attemp...

BACKGROUND Occult hepatitis B infection (OBI) is a form of hepatitis in which there is an absence of detectable HBsAg, despite the presence of HBV-DNA in the peripheral blood of patients. It seems that non-effective or attenuated immune system responses against HBV lead to the development of OBI. Previous studies showed that the Fas/Fas ligand (FasL) system is an important death signaling pathw...

BACKGROUND The current clinical practice on chronic hepatitis B (CHB) requires better on-treatment monitoring of viral persistence. Quantified assays for hepatitis B surface antigen (HBsAg) and core-related antigen (HBcrAg) hold promise for further optimization of therapy. Here, we aimed to characterize HBcrAg during the natural course of CHB. METHODS Four-hundred and forty four treatment naï...

Alginate coated chitosan nanoparticles were previously developed with the aim of protecting the antigen, adsorbed on the surface of those chitosan nanoparticles, from enzymatic degradation at mucosal surfaces. In this work, this new delivery system was loaded with the recombinant hepatitis B surface antigen (HBsAg) and applied to mice by the intranasal route. Adjuvant effect of the delivery sys...