UMLS:C0019163 - FACTA Search

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Query: UMLS:C0019163 (hepatitis B)
38,309 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

To investigate the features of various hepatitis virus infection in intravenous drug users (IVDU), we conducted an epidemiological survey of hepatitis viruses including hepatitis B virus (HBV), hepatitis C virus (HCV), hepatitis D virus (HDV) and hepatitis G virus (HGV) in IVDU. The correlation of TH lymphocyte cytokine and hepatitis virus infection was examined. A study population of 406 IVDU consisted of 383 males and 23 females. HBV-DNA and HCV-RNA were detected by fluorescence quantitative polymerase chain reaction. HBsAg, HBeAg, anti-HBc, anti-HCV, HDV-Ag and anti-HGV were assayed by ELISA. The levels of cytokines of TH1 and TH2 were measured by ELISA. The similar indices taken from 102 healthy persons served as controls. The infection rate of each virus among IVDU was 36.45 % for HBV, 69.7 % for HCV, 2.22 % for HDV, and 1.97 % for HGV, respectively. The co-infection rate of HBV and HCV was detected in 113 of 406 (27.83 %). In contrast, among controls, the infection rate was 17.65 % for HBV and 0 % for the other hepatitis viruses. The levels of PHA-induced cytokines (IFN-gamma and IL-4) and the level of serum IL-2 were obviously decreased in IVDU. On the other hand, the level of serum IL-4 was increased. The IFN-gamma level was continuously decreased when the IVDU was infected with HBV/HCV. In conclusion, HBV and HCV infection were common in this population of IVDU and they had led to a high incidence of impaired TH1 cytokine levels.
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PMID:Epidemiology of hepatitis B, C, D and G viruses and cytokine levels among intravenous drug users. 1685 Jul 52

Alum has been in use since long as an adjuvant for vaccines. However, its use as a vaccine adjuvant offers limitation in supporting cell mediated response. Therefore, a new plant based product RLJ-NE-299A from Picrorhiza kurroa reported for its immunostimulatory activity, has been explored for its potential as an alternative adjuvant. In order to compare the adjuvant activity with alum, antigen-specific immune responses were evaluated following immunization with a formulation containing hepatitis B surface antigen (HBsAg) adjuvanted with RLJ-NE-299A and alum in mice. The adjuvant RLJ-NE-299A up-regulated remarkably the expression of Th1 cytokines IL-2, IL-12, IFN-gamma, TNF alpha and Th2 cytokine IL-4 in lymph node cell cultures after 2 weeks of primary immunization with HBsAg. Further, the levels of both immunoglobulins IgG2a (Th1) and IgG1 (Th2) subtypes increased profoundly in blood sera of mice immunized with HBsAg/RLJ-NE-299A. The results indicated that RLJ-NE-299A has strong potential to increase both cell mediated and humoral immune responses and is capable of sustaining the total antigen-specific antibody response. Besides, the RLJ-NE-299A provides a signal to gear up both CD4 helper cells (Th1 and Th2) and CD8 cells populations, which may have important implications for vaccination against hepatitis B virus. Variable doses of RLJ-NE-299A (0.312-40 microg) containing vaccine antigen (HBsAg) were well tolerated with optimum T cell response at 2.5 microg/ml. Not only this, the adjuvant was also able to induce cellular immune responses to HBsAg as evidenced by Th1 and Th2 cytokines upregulation, which enabled mice to overcome the unresponsiveness to antigen HBsAg encountered with alum-adjuvanted vaccine in otherwise non-responding mice population. The study presents evidence that the HPLC standardized fraction RLJ-NE-299A, is an adjuvant of choice over alum in improving and maintaining the improved immune status against HBsAg, and may also prove useful adjuvant candidate with other vaccine antigens, too.
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PMID:RLJ-NE-299A: a new plant based vaccine adjuvant. 1687 26

The function of Ag-specific central (T(CM)) and effector (T(EM)) memory CD4+ T lymphocytes remains poorly characterized in vivo in humans. Using CD154 as a marker of Ag-specific CD4+T cells, we studied the differentiation of memory subsets following anti-hepatitis B immunization. Hepatitis B surface Ag (HBs)-specific memory CD4+T cells were heterogeneous and included T(CM) (CCR7+CD27+) and T(EM) (CCR7(-)CD27(+/-)). HBs-specific T(CM) and T(EM) shared the capacity to produce multiple cytokines, including IL-2 and IFN-gamma. Several years postimmunization, approximately 10% of HBs-specific memory CD4+ T cells were in cycle (Ki67+) and the proliferating cells were CCR7+. These results suggest that the model of functional specialization of T(CM) and T(EM) cannot be applied to protein vaccine Ags and support the concept that T(CM) are capable of self-renewal and contribute to maintain the pool of memory cells.
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PMID:Antigen-specific central memory CD4+ T lymphocytes produce multiple cytokines and proliferate in vivo in humans. 1711 95

Plasmid DNA vaccines encoding the hepatitis B virus (HBV) surface and hepatitis C virus (HCV) envelope antigens, respectively, were constructed, and attempt were made to find the possibility of a divalent vaccine against HBV and HCV. The expression of each plasmid in Cos-1 cells was confirmed using immunocytochemistry. To measure the induced immune response by these plasmids in vivo, female BALB/c mice were immunized intramuscularly with 100 microg of either both or just one of the plasmids. Anti-HBV and HCV-specific antibodies and related cytokines were evaluated to investigate the generation of both humoral and cellular immune responses. As a result, specific anti-HBV and anti-HCV serum antibodies from mice immunized with these plasmids were observed using immunoblot. The levels of IL-2 and RANTES showing a Th1 immune response were significantly increased, but there was no change in the level of IL-4 (Th2 immune response) in any of the immunized groups. Compared with each plasmid DNA vaccine, the combined vaccine elicited similar immune responses in both humoral and cell-mediated immunities. These results suggest that the combined DNA vaccine can induce not only comparable immunity experimentally without antigenic interference, but also humoral and Th1 dominant cellular immune responses. Therefore, they could serve as candidates for a simultaneous bivalent vaccine against HBV and HCV infections.
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PMID:Modulation of immune response induced by co-administration of DNA vaccine encoding HBV surface antigen and HCV envelope antigen in BALB/c mice. 1714 74

After liver transplantation for hepatitis-B-related diseases, patients currently receive lifelong treatment with hepatitis B immunoglobulin to prevent endogenous reinfection with hepatitis B virus (HBV). Active immunization with hepatitis B vaccine would be a preferable alternative; however, most attempts to immunize these patients with standard vaccine have failed. A recent study with a new adjuvanted hepatitis B vaccine was exceptionally successful, leading to a high-titered long-lasting antibody response in 80% of all vaccinees. To identify the immunological mechanisms behind these unexpected results, the successfully vaccinated participants were tested for hepatitis B surface antigen (HBsAg)-specific T and B cells, and their cellular responses to revaccination with conventional vaccine were studied. HBsAg-specific CD4(+) T lymphocytes could be detected in 13 of 16 patients after immunization with the new vaccine. Unexpectedly, these T cells produced almost exclusively interleukin (IL)-10 and had a CD4(+)/CD25(+) phenotype. They were functionally active, suppressing cytokine secretion in HBsAg-specific (Th1) cells, thus representing antigen-specific regulatory T cells (T(Reg)). Following a booster dose with conventional vaccine 22-31 months after completion of the initial vaccination series, the T-cell pattern in the revaccinated individuals changed substantially: 7 days after revaccination 9 of 11 individuals showed a switch to a Th1-type immune response with HBsAg-specific T cells secreting IL-2, interferon gamma and tumor necrosis factor alpha as observed in healthy controls. Four weeks after the booster, 4 patients still showed a Th1-type cytokine pattern, whereas in 5 patients only IL-10-secreting cells were detectable. After 1 year, in 3 of 4 revaccinated individuals only IL-10-secreting cells could be found, whereas the specific T cells of the fourth patient still showed a Th1-type of response. HBsAg-specific T(Reg) cells could be demonstrated in HBV-positive liver transplant recipients successfully immunized with a new adjuvanted vaccine. Revaccination led to immediate disappearance of the these cells and the appearance of HBsAg-specific T cells with a Th1-type cytokine profile, which in most cases were replaced by the IL-10-secreting regulatory cells during the following months. The specific induction of T(Reg) cells could contribute to the poor response of liver transplant recipients to conventional vaccine. In conclusion,, for successful vaccination of these patients, a vaccine with a strong inhibitory effect on T(Reg) cells would be desirable.
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PMID:Vaccination against hepatitis B in liver transplant recipients: pilot analysis of cellular immune response shows evidence of HBsAg-specific regulatory T cells. 1731 60

There is a clinical need for a more effective vaccine against hepatitis B, and in particular vaccines that may be suitable for therapeutic administration. This study assesses the potential of cationic surfactant vesicle based formulations using two agents; the cationic amine containing [N-(N',N'-dimethylaminoethane)-carbamoyl] cholesterol (DC-Chol) or dimethyl dioctadecylammonium bromide (DDA) with hepatitis B surface antigen (HBsAg). Synthetic mycobacterial cord factor, trehalose 6,6'-dibehenate (TDB) has been used as an adjuvant and the addition of 1-monopalmitoyl glycerol (C16:0) (MP) and cholesterol (Chol) to DDA-TDB is assessed for its potential to facilitate formation of dehydration-rehydration vesicles (DRV) at room temperature, and the effect of this on immune responses. A DRV formulation is directly compared to an adsorbed formulation of the same composition and preparation protocol (MP:dioleoyl phosphoethanolamine (DOPE):Chol:DC-Chol) and the direct substitution of MP with phosphatidylcholine (PC) is also compared in DRV antigen-entrapped formulations. MP and Chol were shown to facilitate the use of DDA-TDB in DRV formulations prepared at room temperature, whilst there was marginal alteration of immunogenicity (a reduction in HBsAg-specific IL-2). The HBsAg adsorbed DRV formulation was not significantly different from the HBsAg entrapped DRV formulation. Overall, DDA formulations incorporating TDB showed markedly increased antigen specific splenocyte proliferation and elicited cytokine production concomitant with a strong T cell driven response, delineating formulations that may be useful for further evaluation of their clinical potential.
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PMID:Comparison of vesicle based antigen delivery systems for delivery of hepatitis B surface antigen. 1733 10

DNA vaccines have been shown to elicit both cellular and humoral immune responses and to be effective in a variety of preclinical bacterial, viral, and parasitic animal models. We have recently described a needle-free method of vaccination, transcutaneous immunization, based on topical application of vaccine antigens on intact skin using a novel carrier system, namely transfersomes. In the present study, a novel modified version of transfersomes, i.e., cationic transfersomes for topical DNA vaccine delivery has been developed. Cationic transfersomes composed of cationic lipid DOTMA and sodium deoxycholate as constitutive lipids were prepared and optimized for their size, shape, zeta potentials, deformability and loading efficiency. Plasmid DNA encoding hepatitis B surface antigen (HBsAg) was loaded in the cationic transfersomes using charge neutralization method. The immune stimulating activity was studied by measuring serum anti-HBsAg titer and cytokines level (IL-2 and IFN-gamma) following topical applications of plasmid DNA loaded cationic transfersomes in Balb/c mice and results were compared with naked DNA applied topically as well as naked DNA and pure recombinant HBsAg administered intramuscularly. Results revealed that DNA loaded cationic transfersomes elicited significantly (*P<0.05) higher anti-HBsAg antibody titer and cytokines level as compared to naked DNA. It was also observed that topical application of DNA loaded cationic transfersomes elicited a comparable serum antibody titer and endogenous cytokines levels as produced after intramuscular recombinant HBsAg administration. The study signifies the potential of cationic transfersomes as DNA vaccine carriers for effective topical immunization.
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PMID:Cationic transfersomes based topical genetic vaccine against hepatitis B. 1744 15

Immunopathogenesis of chronic viral hepatitides was studied by modern immunological, molecular, genetic methods. We revealed an imbalance in the production of immunoregulatory cytokines by mononuclear leukocytes (primarily of the Th2 type). The risk of progression and chronic course of viral hepatitides in Caucasian population was associated with alleles of promoter regions -330G and -592A in the IL-2 and IL-10 genes, respectively, as well as with the T/T genotype of the polymorphic region C590T in the IL-4 gene. The C/C genotype of the IL-10 gene promoter region C592A was shown to be a factor determining resistance to long-term persistence of hepatitis B and C viruses.
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PMID:Role of genetically determined production of immunoregulatory cytokines in immunopathogenesis of chronic viral hepatitides. 1823 7

A randomised, double-blind study assessing the potential of four adjuvants in combination with recombinant hepatitis B surface antigen has been conducted to evaluate humoral and cell-mediated immune responses in healthy adults after three vaccine doses at months 0, 1 and 10. Three Adjuvant Systems (AS) contained 3-O-desacyl-4'-monophosphoryl lipid A (MPL) and QS21, formulated either with an oil-in-water emulsion (AS02B and AS02V) or with liposomes (AS01B). The fourth adjuvant was CpG oligonucleotide. High levels of antibodies were induced by all adjuvants, whereas cell-mediated immune responses, including cytolytic T cells and strong and persistent CD4(+) T cell response were mainly observed with the three MPL/QS21-containing Adjuvant Systems. The CD4(+) T cell response was characterised in vitro by vigorous lymphoproliferation, high IFN-gamma and moderate IL-5 production. Antigen-specific T cell immune response was further confirmed ex vivo by detection of IL-2- and IFN-gamma-producing CD4(+) T cells, and in vivo by measuring increased levels of IFN-gamma in the serum and delayed-type hypersensitivity (DTH) responses. The CpG adjuvanted vaccine induced consistently lower immune responses for all parameters. All vaccine adjuvants were shown to be safe with acceptable reactogenicity profiles. The majority of subjects reported local reactions at the injection site after vaccination while general reactions were recorded less frequently. No vaccine-related serious adverse event was reported. Importantly, no increase in markers of auto-immunity and allergy was detected over the whole study course. In conclusion, the Adjuvant Systems containing MPL/QS21, in combination with hepatitis B surface antigen, induced very strong humoral and cellular immune responses in healthy adults. The AS01B-adjuvanted vaccine induced the strongest and most durable specific cellular immune responses after two doses. These Adjuvant Systems, when added to recombinant protein antigens, can be fundamental to develop effective prophylactic vaccines against complex pathogens, e.g. malaria, HIV infection and tuberculosis, and for special target populations such as subjects with an impaired immune response, due to age or medical conditions.
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PMID:Vaccine adjuvant systems containing monophosphoryl lipid A and QS21 induce strong and persistent humoral and T cell responses against hepatitis B surface antigen in healthy adult volunteers. 1827 64

Serologic responses to T cell-dependent vaccinations are severely attenuated in patients with ESRD, but the reasons for this is unknown. In this study, a detailed analysis of antigen-specific T cell responses was performed. Patients on hemodialysis and age- and gender-matched healthy control subjects were vaccinated with hepatitis B surface antigen (HBsAg), antigen-specific CD4(+) T cells were monitored at regular intervals with intracellular cytokine staining and proliferation assays. IL-2-and IFN-gamma-producing CD4(+) T cells were identified as either central or effector memory CD4(+) T cells using antibodies directed against CD45RO and the chemokine receptor CCR7. Control subjects mounted a memory T cell response comprising both central and effector memory CD4(+) T cells, with the central memory response occurring 1 wk before the effector memory response. IL-2(+) HBsAg-specific memory CD4(+) T cells were primarily detected within the effector population. Patients with ESRD showed a delayed response of IL-2-and IFN-gamma-producing central memory CD4(+) T cells, but their maximal responses were similar to those of control subjects. In contrast, patients with ESRD produced only 6.3% of the IL-2(+) HBsAg-specific effector memory CD4(+) T cells produced by control subjects (0.5 +/- 0.2 x 10(4)/L versus 8 +/- 3.5 x 10(4)/L; P < 0.001), and this impaired response correlated with antigen-specific T cell proliferation and anti-HBsAg IgG titers. In conclusion, the production of antigen-specific effector memory CD4(+) T cells after vaccination, which is critical to achieve an adequate humoral response, is severely impaired in patients with ESRD.
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PMID:Impaired immune responses and antigen-specific memory CD4+ T cells in hemodialysis patients. 1848 Mar 14

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