Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: UMLS:C0023890 (cirrhosis)
 42,195 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

An improved ability to monitor hepatitis C virus (HCV)-specific T cell immunity in infected patients may provide novel information regarding the pathogenesis and prognosis of this infection. We used an ELISPOT assay to analyze a cross-section of HCV-infected humans. HCV-infected patients without cirrhosis, those with cirrhosis, and controls with other liver diseases were tested for recall responses to HCV Core and NS3 proteins. Peripheral blood lymphocytes (PBLs) from HCV-infected patients without cirrhosis responded to NS3 and Core proteins, producing predominantly IFN-gamma, with little IL-4 or IL-5. In contrast, PBLs from HCV-infected patients with cirrhosis responded to NS3, but not to the Core protein, suggesting a selectively altered immune state during cirrhosis. Our data provide support for the notion that HCV-specific IFN-gamma-producing immunity is important in the pathogenesis of progressing HCV-related disease.
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PMID:ELISPOT analysis of hepatitis C virus protein-specific IFN-gamma-producing peripheral blood lymphocytes in infected humans with and without cirrhosis. 1131 95

The mechanism by which Hepatitis C virus(HCV) infection promotes the development of hepatocellular carcinoma(HCC) is not known exactly. HCV related HCC occurs frequency in the patients with cirrhosis. There have been reports indicating that Th2-type cytokines down-regulated antitumor immunity, and the activation of type 1 T cell responses produced antitumor immunity. We thought Th1/Th2 imbalance in HCV-related liver cirrhosis might be closely related to the development of HCC. In this study, therefore, we investigated the Th1/Th2 balance at the single lymphocyte level of the patients with HCV-related liver cirrhosis and compared with normal controls by using flow cytometry. Th1-type cytokines(IFN-gamma, IL-2) production was significantly decreased in patients with cirrhosis, whereas Th2-type cytokine production(IL-10) was increased. These suggest Th1/Th2 imbalance in HCV-related cirrhosis would decrease the antitumor immunity and its improvement might present the protective effect from HCC.
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PMID:[Th1/Th2 imbalance in HCV-related liver cirrhosis]. 1149 34

Persistent infection with hepatitis C virus (HCV) is a major cause of chronic hepatitis, liver cirrhosis, and hepatocellular carcinoma. All treatments known so far rely on the antiviral activity of interferon alfa (IFN-alpha) that is given alone or in combination with ribavirin. Unfortunately, only a fraction of the patients clear the virus during therapy and for those who do not respond there is currently no alternative treatment. Selectable subgenomic HCV RNAs (replicons) have been recently used to investigate the effect of IFN-alpha on HCV replication. However, it has not yet been analyzed whether other cytokines also play a role in the innate immune response against HCV. Here we show that IFN-gamma inhibits protein synthesis and RNA replication of subgenomic and genomic HCV replicons. We further show that the inhibitory action of IFN-gamma does not rely on the production of nitric oxide or the depletion of tryptophan. In conclusion, our results suggest that cytotoxic T cells and natural killer cells may contribute to HCV clearance not only by cell killing but also by producing IFN-gamma, thereby enhancing the intracellular inhibition of viral replication.
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PMID:Interferon-gamma inhibits replication of subgenomic and genomic hepatitis C virus RNAs. 1187 Mar 86

Patients with hepatitis C virus (HCV) related-liver cirrhosis (LC) often develop hepatoma. The type 1 helper T cell (Th1) response presents an antitumor effect. We evaluated the Th1 response in patients with HCV-related LC at the single-cell level and examined the influence of transforming growth factor (TGF)-beta, an immunosuppressive cytokine, on the Th1 response. We determined the ratios of Th1-type cytokine (IFN-gamma, IL-2)-producing cells to CD3-positive cells in 14 patients (LC group) and in 16 normal controls using flow cytometry and measured serum TGF-beta(1) and TGF-beta(2) levels by ELISA. We then incubated, peripheral blood mononuclear cells from seven healthy volunteers with recombinant TGF-beta(1) or TGF-beta(2) for 48 h, and determined the ratio of IFN-gamma producing cells to CD3-positive cells. The IFN-gamma ratio was significantly lower in the LC group (29.7+/-0.3 vs. 44.2+/-15.0%, P<0.01). The serum TGF-beta(2) level was significantly increased in the LC group (601+/-232 vs. 329+/-118 pg/ml, P<0.001). TGF-beta(2) significantly suppressed IFN-gamma production at the single-cell level (10.0+/-4.3 vs. 7.3+/-2.0%, P<0.05). These findings indicated that the enhanced down-regulation of Th1 by TGF-beta(2) in patients with HCV-related LC might be effective against hepatoma.
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PMID:Th1 down-regulation at the single-lymphocyte level in HCV-related liver cirrhosis and the effect of TGF-beta on Th1 response: possible implications for the development of hepatoma. 1239 30

The HBx-derived, HLA-A2.1 restricted peptides, XEP-3, XEP-4, and XEP-6, induced activation of specific CTLs from patients with HBV in vitro. XEP-6 peptide induced the strongest response among the three peptides in CTLs from the blood samples of patients that were HBsAg positive. It was not clear whether the stage of disease (chronic infection, cirrhosis or hepatoma) was related to the responsiveness of the CTLs to each peptide. We vaccinated HLA-A2/K(b) transgenic mice with these peptides encapsulated in pH-sensitive liposomes at various concentrations and tested their ability to protect against challenge with rVV-HBx. Mice immunized with encapsulated peptides were protected against viral challenge whereas those immunized with empty liposomes were not. In general, 5 micro g of each peptide per head inoculation was sufficient to give protection after 2 weeks. After 3 weeks, this protective effect was increased. This effect of time was more important on the level of protection than the initial dose of the peptide. To explain the protective effect, IFN-gamma secreting CD8(+) cells isolated from mice 3 weeks after immunization were analyzed ex vivo. There was little dose dependency of peptide on IFN-gamma secretion except for XEP-3. The variations in the results may reflect the chemical properties of the peptides, such as solubility and binding affinity. In conclusion, epitope peptides derived from HBx can induce specific CTL activation and lead to cellular immunity in vitro and in vivo by inducing the peptide-specific CD8(+) CTLs. Thus, pH-sensitive liposomes increase the immune response following immunization with a peptide vaccine. This could be used for the treatment of HBV-related disease.
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PMID:HLA-A2 1 restricted peptides from the HBx antigen induce specific CTL responses in vitro and in vivo. 1239 8

The liver plays an important physiological role in lipopolysaccharide (LPS) detoxification and, in particular, hepatocytes are involved in the clearance of endotoxin of intestinal derivation. In experimental shock models, tumor necrosis factor (TNF)-alpha induces hepatocyte apoptosis and lethal effects are due to secreted TNF-alpha and not to cell-associated TNF-alpha. An exaggerated production of TNF-alpha has been reported in murine viral infections, in which mice become sensitized to low amounts of LPS and both interferon (IFN)-gamma and IFN-alpha/beta are involved in the macrophage-induced release of TNF-alpha. The prominent role of LPS and TNF-alpha in liver injury is also supported by studies of ethanol-induced hepatic damage. In humans, evidence of LPS-induced hepatic injury has been reported in cirrhosis, autoimmune hepatitis, and primary biliary cirrhosis and a decreased phagocytic activity of the reticulo-endothelial system has been found in these diseases. The origin of endotoxemia in hepatitis C virus (HCV) infected patients seems to be multifactorial and LPS may be of exogenous or endogenous derivation. In endotoxemic HCV-positive patients responsive to a combined treatment with IFN-alpha/ribavirin (RIB), endotoxemia was no longer detected at the end of the therapeutic regimen. By contrast, 48% of the non-responders to this treatment were still endotoxemic and their monocytes displayed higher intracellular TNF-alpha and interleukin (IL)-1beta levels than responders. Moreover, in responders, an equilibrium between IFN-gamma and IL-10 serum levels was attained. In the non-responders, serum levels of IL-10 did not increase following treatment. This may imply that an imbalance between T helper (Th)1 and Th2 derived cytokines could be envisaged in the non-responders.
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PMID:The role of the liver in the response to LPS: experimental and clinical findings. 1253 90

Chronic hepatitis B virus (HBV) infection can cause a broad spectrum diseases, including from asymptomatic HBV carriers or cryptic hepatitis, to acute hepatitis, chronic hepatitis, Liver cirrhosis and primary hepatocellular carcinoma. The variable pattern and clinical outcome of the infection were mainly determined by virological itself factors, host immunological factors and genetic factors as well as the experimental factors. Among the human genetic factors, major candidate or identified genes involved in the process of HBV infection fall into the following categories: (1) genes that mediate the processes of viral entry into hepatocytes, including genes involved in viral binding, fusion with cellular membrane and transportation in target cells; (2) genes that modulate or control the immune response to HBV infection; (3) genes that participate in the pathological alterations in liver tissue; (4) genes involved in the development of liver cirrhosis and hepatocellular carcinoma associated with chronic HBV infection, including genes related to mother-to-infant transmission of HBV infection; and (5) those that contribute to resistance to antiviral therapies. Most of the reports of human genes associated with HBV infection have currently focused on HLA associations. For example, some investigators reported the association of the HLA class II alleles such as DRB1*1302 or HLA-DR13 or DQA1*0501-DQB1*0301-DQB1*1102 haplotypes with acute and/or chronic hepatitis B virus infection, respectively. Several pro-inflammatory cytokines such as Th1 cytokines (including IL-2 and IFN-gamma) and TNF-alpha have been identified to participate the process of viral clearance and host immune response to HBV. In contrast, the Th2 cytokine IL-10 serves as a potent inhibitor of Th1 effector cells in HBV diseases. The MBP polymorphisms in its encoding region were found to be involved in chronic infection. Thus, reports from various laboratories have shown some inconsistencies with regard to the effects of host genetic factors on HBV clearance and persistence. Since genetic interactions are complex, it is unlikely that a single allelic variant is responsible for HBV resistance or susceptibility. However, the collective influence of several single nucleotide polymorphisms (SNPs) or haplotype (s) may underlie the natural combinational or synergistic protection against HBV. The future study including the multi-cohort collaboration will be needed to clarify these preliminary associations and identify other potential candidate genes. The ongoing study of the distributions and functions of the implicated allele polymorphisms will not only provide insight into the pathogenesis of HBV infection, but may also provide a novel rationale for new methods of diagnosis and therapeutic strategies.
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PMID:Current status and prospects of studies on human genetic alleles associated with hepatitis B virus infection. 1267 1

IL-18 is a pleiotropic cytokine and is produced by various types of cells including activated macrophages, particularly Kupffer cells. IL-18 has potential to activate inflammatory responses through induction of IFN-gamma production in collaboration with IL-12. Somewhat paradoxically, IL-18 also has the capacity to induce allergic responses via induction of IL-4 production by T helper cells and to activate mast cells and basophils to release atopic effector molecules such as histamine. Indeed, IL-18 is involved in inflammatory tissue injuries, such as Crohn's disease and atherosclerosis, and also in hyper IgE and atopic dermatitis. IL-18 is particularly important for induction of experimental liver diseases. Endotoxin-induced liver injury or Fas ligand-induced hepatitis is caused by endogenous IL-18 in mice. Moreover, patients with liver diseases such as fulminant hepatitis, liver cirrhosis due to hepatitis virus infection and primary biliary cirrhosis show elevation of serum levels of IL-18, that correlates with the corresponding disease severity. Therefore, endogenous IL-18 plays a major role in induction of some types of liver injuries in mice and human. NKT cells that express both T cell receptor and NK cell marker are abundant in the liver of mice and human. Recent studies have revealed that NKT cells participate in some types of liver injuries, such as concanavalin A-induced T cell-mediated hepatitis and malaria hepatitis. In this review article, we focus on IL-18-involving liver damages and NKT-cell-mediated liver injuries.
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PMID:Cytokine-induced inflammatory liver injuries. 1452 86

Alterations in immunological defense in the gut may lead to the bacterial infection that is frequently associated with cirrhosis of the liver. The aim of this study was to investigate the changes in distribution and function of intestinal intraepithelial lymphocytes (IELs) in relation to intestinal barrier dysfunction in experimental cirrhosis. Cirrhosis was induced in mice by treatment with carbon tetrachloride (CCl4) intraperitoneally with 5% alcohol in drinking water for 12 weeks. Bacterial translocation was assessed in mesenteric lymph nodes (MLNs) by the transport of fluorescence-labeled latex beads and by bacteriological cultures. The lymphocyte subpopulation was compared in three groups (cirrhosis, alcohol alone and controls). IFN-gamma production from isolated IELs was determined by ELISA after stimulation with anti-CD3 or IL-12/IL-18. The total number of IELs significantly increased in the cirrhosis and alcohol groups. There was a preferential increase in TCRgammadelta+CD8+ population in the alcohol group, but no change in cirrhosis. Bacterial translocation was negative in the control group, and a small number was noted in the alcohol group, whereas it was significantly noted in the cirrhosis group. Although the number of IEL was significantly increased in the cirrhosis group, their proliferative response was decreased, and IFN-gamma production from each IEL was markedly diminished in either stimulation by anti-CD3 or IL-12/IL-18. These changes were more remarkable in the cirrhosis group than in the alcohol group. In conclusion, bacterial translocation due to intestinal barrier dysfunction in cirrhosis may be closely correlated with the alteration of the immune function in IELs.
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PMID:Alteration of intestinal intraepithelial lymphocytes and increased bacterial translocation in a murine model of cirrhosis. 1461 1

In patients with hepatocellular carcinoma (HCC), natural killer (NK) cell activity decreases significantly, and the reduced activity may be associated with the progression of HCC. In this study we evaluated the effects of pulsing with interleukin (IL)-2 and/or IL-12 on the activation of freshly isolated peripheral blood lymphocytes (PBL) derived from patients with HCC. PBL obtained from 9 HCC patients, 4 liver cirrhosis patients, and 9 normal subjects were cultured in the presence of IL-2 and/or IL-12. After 24 h of incubation, the levels of interferon (IFN)-gamma and tumor necrosis factor (TNF)-alpha presented in the supernatants were determined by enzyme-linked immunosorbent assay (ELISA). The IFN-gamma and TNF-alpha production of PBL pulsed by a combination of IL-2 and IL-12 was significantly higher than those of PBL stimulated by either IL-2 or IL-12 alone. The mRNA encoding perforin, granzyme B, as well as IFN-gamma and TNF-alpha, were markedly enhanced in PBL stimulated with a combination of IL-12 and IL-2. The pulsing procedure of IL-12 in combination with IL-2 resulted in the increase of IFN-gamma and TNF-alpha, and the expression of perforin and granzyme B mRNA in PBL obtained from HCC patients, as well as in those obtained from normal subjects. These results indicate that adoptive immunotherapy based on PBL pulsed with a combination of IL-2 and IL-12 may be a promising adjunctive strategy for HCC treatment.
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PMID:Effects of pulsing procedure of interleukin-12 in combination with interleukin-2 on the activation of peripheral blood lymphocytes derived from patients with hepatocellular carcinoma. 1472 65


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