Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0019158 (hepatitis)
 30,205 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

A mechanism of liver injury such as, viral hepatitis or autoimmune hepatitis is considered to involve the impairment of hepatocytes mainly mediated by T-cell immunity, but the roles of a variety of cytokines involved in regulation remain unclarified. We investigated the involvement of various cytokines, particularly, interleukin-10 (IL-10) which is considered to be an anti-inflammatory cytokine, in a murine model of experimental liver injury induced by Concanavalin A (Con A). The model of liver injury was made by intravenous injection of Con A (0.5 &mgr;g) through the caudal vein in 6-week-old female BALB/c mice weighting 20 g. By collecting blood before and at 1, 3, 6, 12 and 24 h after the injection of Con A, alanine aminotransferase (ALT) levels were sequentially measured, and liver tissue was sampled to examine liver injury. Furthermore, TNF-alpha, IL-4 and IL-10 levels were sequentially determined by enzyme-linked immunosorbent assay (ELISA). Serum ALT significantly increased between 3 and 24 h after the Con A injection, and spotty necrosis was histologically observed, suggesting mild liver injury. TNF-alpha and IL-4 increased soon after the injection of Con A. IL-10 increased bimodally soon after and at 12 h after the Con A injection. After neutralizing antibodies (1 &mgr;g) to IL-10 were intraperitoneally injected into the same model at 6 h before Con A treatment, serum ALT levels and the histology of the liver were examined 12 h after the Con A injection. ALT was significantly higher in the group treated with anti-IL-10 antibody (130.7+/-33.5 IU per I) than in the non-treated group (56.5+/-3.5 IU per I) (P<0.05). Histological examination showed spotty necrosis in the group treated with anti-IL-10 antibody. These results suggest that IL-10 has inhibitory effect on liver injury in a murine model of Con A-induced experimental liver injury mediated by cellular immunity.
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PMID:Involvement of IL-10, an anti-inflammatory cytokine in murine liver injury induced by Concanavalin A. 1134 58

Suppressor of cytokine signaling-1 (SOCS-1), also known as STAT-induced STAT inhibitor-1 (SSI-1), is a negative feedback molecule for cytokine signaling, and its in vivo deletion induces fulminant hepatitis. However, elimination of the STAT1 or STAT6 gene or deletion of NKT cells substantially prevented severe hepatitis in SOCS-1-deficient mice, while administration of IFN-gamma and IL-4 accelerated its development. SOCS-1 deficiency not only sustained IFN-gamma/IL-4 signaling but also eliminated the cross-inhibitory action of IFN-gamma on IL-4 signaling. These results suggest that SOCS-1 deficiency-induced persistent activation of STAT1 and STAT6, which would be inhibited by SOCS-1 under normal conditions, may induce abnormal activation of NKT cells, thus leading to lethal pathological changes in SOCS-1-deficient mice.
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PMID:SOCS-1/SSI-1-deficient NKT cells participate in severe hepatitis through dysregulated cross-talk inhibition of IFN-gamma and IL-4 signaling in vivo. 1137 56

Murine intrahepatic lymphocytes (IHL) are dominated by invariant TCR alpha-chain expressing CD1d-reactive NKT cells, which can cause model hepatitis. Invariant NKT (CD56(+/-)CD161(+)) and recently identified noninvariant CD1d-reactive T cells rapidly produce large amounts of IL-4 and/or IFN-gamma and can regulate Th1/Th2 responses. Human liver contains large numbers of CD56(+) NKT cells but few invariant NKT. Compared with matched peripheral blood T cell lines, primary IHL lines from patients with chronic hepatitis C had high levels of CD161 and CD1d reactivity, but the invariant TCR was rare. CD1d-reactive IHL were strikingly Th1 biased. IHL also demonstrated CD1d-specific cytotoxic activity. Hepatocytes and other liver cells express CD1d. These results identify a novel population of human T cells that could contribute to destructive as well as protective immune responses in the liver. CD1d-reactive T cells may have distinct roles in different tissues.
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PMID:Cutting edge: Compartmentalization of Th1-like noninvariant CD1d-reactive T cells in hepatitis C virus-infected liver. 1182 74

Recurrent chronic hepatitis, cholestatic hepatitis, and acute rejection in conjunction with hepatitis C virus (HCV) recurrence are well-recognized clinical sequelae of reinfection of the hepatic allograft with HCV. The aim of this study is to characterize intrahepatic cytokine responses associated with reinfection of the allograft with HCV in these settings. Intrahepatic messenger RNA expression of T helper cell subtype 1 (TH1) cytokines interleukin-2 (IL-2), interferon-gamma, and tumor necrosis factor-alpha and TH2 cytokines IL-4 and IL-10 was measured by real-time polymerase chain reaction system using TaqMan probes in 53 liver specimens from six groups of patients. These were: (1) recurrent chronic hepatitis C (CH-I; n = 15), (2) cholestatic hepatitis (n = 6), (3) acute rejection associated with HCV recurrence (AR-HCV; n = 12), (4) acute rejection in non-HCV-infected allografts (AR non-HCV; n = 5), (5) patients with chronic hepatitis C who did not undergo transplantation (CH-C; n = 10), and (6) non-diseased liver tissue (n = 6). Intrahepatic viral loads were measured using an Amplicor monitor assay (Roche Diagnostic Systems, Branchburg, NJ). The CH-I and CH-C groups had similar TH1 intrahepatic cytokine profiles. Compared with the CH-I group, the cholestatic group expressed increased levels of the TH2 cytokines IL-10 (P =.024) and IL-4 (P =.0024). The AR-HCV group also expressed more TH2 cytokines IL-10 (P =.014) and IL-4 (P =.034) compared with the CH-I group. Both the AR-HCV and AR non-HCV groups showed similar intrahepatic cytokine profiles. Intrahepatic viral loads were highest in the cholestatic group compared with the AR-HCV, CH-I, and CH-C groups (P =.0007). In conclusion, a novel observation is that the cholestatic group showed upregulation of the TH2 cytokines IL-10 and IL-4, in addition to high viral loads. In this setting, the TH2 immune response may favor viral replication and graft damage.
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PMID:Intrahepatic cytokine profiles associated with posttransplantation hepatitis C virus-related liver injury. 1191 May 76

Real-time polymerase chain reaction (PCR) assays were developed for woodchuck leukocyte cluster of differentiation (CD) and cytokine mRNA expression. Plasmid DNA standards of each marker (CD3, CD4, CD8, IL-2, IFN-gamma, TNF-alpha, IL-4, IL-10), and RNA standards from mitogen-stimulated woodchuck peripheral blood mononuclear cells (PBMCs) were used to validate and optimize the assays for TaqMan 7700 and iCycler PCR instruments. The complementary DNAs (cDNAs) produced by reverse transcription (RT) of RNA were quantified by real-time PCR against the plasmid DNA standards (6-8 log range) with detection of as few as 10-50 copies of amplicon cDNA per reaction. Analysis of unstimulated and concanavalin A-stimulated woodchuck PBMC demonstrated increased CD and cytokine mRNA expression following mitogenic activation. A liver sample from a woodchuck hepatitis virus (WHV) infected woodchuck with histologically confirmed acute hepatitis had increased intrahepatic CD and cytokine mRNAs compared to liver from an uninfected control woodchuck. The real-time PCR assays were highly specific for the woodchuck markers in PBMC and liver samples and were equally applicable for use in alternate real-time PCR instrumentation. These assays will enable the high-throughput analyses of mRNA markers during WHV infection, and thereby facilitate continued modelling of the immunopathogenesis and immunotherapy of human hepatitis B virus (HBV) infection.
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PMID:Real-time polymerase chain reaction assays for leukocyte CD and cytokine mRNAs of the Eastern woodchuck (Marmota monax). 1205 47

The activation of T-cells and macrophages and subsequent induction of cytokines are critical factors in the development of hepatitis. Up-regulation of pro-inflammatory cytokines, e.g. TNF has been shown to induce liver injury while counter regulation by anti-inflammatory cytokines, e.g. IL-10 is protective. We compared the induction of liver injury and the expression pattern of a variety of cytokines in T-cell- versus non-T-cell-dependent mouse models of liver injury. TNF, IFNgamma, IL-2, IL-4, IL-6, IL-10 and IL-12 were measured in plasma and liver tissue after either Concanavalin A (Con A), D-galactosamine/lipopolysaccharide (GalN/LPS) or high dose LPS induced liver injury. Additionally, the intra-hepatic expression of the putative pathogenicity factor high mobility group 1 protein (HMG-1) was compared in all three models.
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PMID:Cytokine expression in three mouse models of experimental hepatitis. 1224 77

The immunoregulatory roles of interleukin-2 (IL-2), IL-4, IL-10, gamma interferon (IFN-gamma), tumor necrosis factor alpha (TNF-alpha), the soluble form of the IL-2 receptor (sIL-2R), and the soluble form of CD30 (sCD30) were evaluated in patients with hepatitis B virus (HBV) infection. Two groups of subjects were studied: 15 healthy individuals without hepatitis antecedents and 15 patients with HBV infection. Blood samples were taken during the acute and convalescent phases. The analysis of the samples was done by the enzyme-linked immunosorbent assay technique. IFN-gamma and TNF-alpha levels decreased in the convalescent phase. IL-10, IL-2, and sIL-2R levels increased in the acute and convalescent phases, while sCD30 levels increased during the acute phase. The IL-4 concentrations decreased in both phases. During the acute phase, IFN-gamma and TNF-alpha induced increases in IL-2, sIL-2R, IL-10, and sCD30 levels in serum, which allowed the development of immunity characterized by the nonreactivity of the HBV surface antigen, the onset of antibodies to the HBV surface antigen (anti-HBs), and normal alanine aminotransferase levels during the convalescent phase. Increased IL-2 levels during the acute phase would stimulate the activities of NK cells and CD8(+) lymphocytes, which are responsible for viral clearing. The raised sIL-2R levels reveal activation of T lymphocytes and control of the IL-2-dependent immune response. The sCD30 increment during the acute phase reflects the greater activation of the Th2 cellular phenotype. Its decrease in the convalescent phase points out the decrease in the level of HBV replication. The increase in IL-10 levels could result in a decrease in IL-4 levels and modulate IFN-gamma and TNF-alpha levels during both phases of disease, allowing the maintenance of anti-HBs concentrations.
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PMID:Concentrations of cytokines, soluble interleukin-2 receptor, and soluble CD30 in sera of patients with hepatitis B virus infection during acute and convalescent phases. 1241 77

Alfa-Galactosyl Ceramide was isolated from Ocean sponge which has antitumor effect against several tumors in in vivo animal model with no cytotoxicity. KRN7000(KRN) is the most potent alpha-Galactosyl Ceramide modified from the one isolated from Ocean sponge. KRN is also active against metastatic tumors through the activation ofanimal immune system. Research efforts in learning the mechanism of action, we found the important role of dendritic cells(DC) and NKT cells. NKT cells was first characterized in 1988 which is overlap some part with NK cells and T-Cells and majority is different from NK and T. KRN is active through the activation of DC and NKT in giving antigen specific immune stimulation in animal. This antigen specific stimulation is memorized by immune system and can reject second tumor challenge. KRN is not active in nude mice and NKT deficient animal. NKT cells level in blood is lower in patients with autoimmune disease, cancer, HIV positive or aplastic anemia. NKT rapidly releases IL-4 and IFN-gamma at high level when activated. NKT is CD1d and TCR restricted. NKT plays important role in autoimmune disease such as Type 1 Diabetes, Scleroderma and Systemic Lupus Erythematosus, infections such as Mycobacteria, Listeria and Malaria, GVHD control and tumor rejection. NKT acts as double edge sword, aggressive and suppressive ways. KRN can prevent the onset of Type 1 Diabetes, inhibit replication of hepatitis virus B in liver and suppress malaria replication in activating NKT cells. KRN can activate NKT through DC and activated NKT activates NK, T and macrophage. KRN also expands NKT cells and expanded NKT has full function. Although the exact role of DC and NKT is not clear, KRN clinical study results in conjunction with DC and NKT cell activation are expected.
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PMID:Role of NKT cells and alpha-galactosyl ceramide. 1243 Aug 64

In autoimmune hepatitis, strong TGF-beta1 expression is found in the inflamed liver. TGF-beta overexpression may be part of a regulatory immune response attempting to suppress autoreactive T cells. To test this hypothesis, we determined whether impairment of TGF-beta signaling in T cells leads to increased susceptibility to experimental autoimmune hepatitis (EAH). Transgenic mice of strain FVB/N were generated expressing a dominant-negative TGF-beta type II receptor in T cells under the control of the human CD2 promoter/locus control region. On induction of EAH, transgenic mice showed markedly increased portal and periportal leukocytic infiltrations with hepatocellular necroses compared with wild-type mice (median histological score = 1.8 +/- 0.26 vs. 0.75 +/- 0.09 in wild-type mice; P < 0.01). Increased IFN-gamma production (118 vs. 45 ng/ml) and less IL-4 production (341 vs. 1,256 pg/ml) by mononuclear cells isolated from transgenic livers was seen. Impairment of TGF-beta signaling in T cells therefore leads to increased susceptibility to EAH in mice. This suggests an important role for TGF-beta in immune homeostasis in the liver and may teleologically explain TGF-beta upregulation in response to T cell-mediated liver injury.
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PMID:Impairment of TGF-beta signaling in T cells increases susceptibility to experimental autoimmune hepatitis in mice. 1246 45

Non-human primates could prove to be suitable models for the study of infectious diseases such as malaria, tuberculosis, and hepatitis; the molecules of their immune systems are in the process of being fully characterized. Due to the relevance of cytokines in the modulation of the immune response, a molecular analysis of these proteins in non-human primates from the Aotus genus was carried out. Peripheral blood mononuclear cells from four species of Aotusmonkey were obtained and their mRNAs for interleukin-2 (IL-2), IL-4, IL-6, IL-10, interferon-gamma (IFN), and tumor necrosis factor (TNF)-alpha were characterized. This study shows a high degree of conservation between nucleotide and amino acid sequences of cytokines from different Aotus species and those from humans. The TNF-alpha molecules were identical in amino acid sequences for both.
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PMID:Identification, cloning, and sequencing of different cytokine genes in four species of owl monkey. 1246 97


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