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)

The aim was to assess the specificity and functional significance of liver-infiltrating and peripheral blood T cells in chronic hepatitis C. Peripheral blood mononuclear cells hepatitis C virus from 50 of 58 (86.2%) patients with chronic hepatitis C virus infection and 6 of 28 (21.4%) controls showed a proliferative T cell response to at least one of 16 synthetic peptides covering highly conserved regions of the core, envelope (El) and non-structural regions (NS4) of hepatitis C virus. However, six immunodominant peptides were exclusively recognized by the proliferating blood mononuclear cells from 46 patients with chronic hepatitis C virus infection (79.3%). Fine specificity and HLA-restriction were studied with 15 peptide-specific CD4+ T cell lines and 23 T cell clones isolated from liver tissue and peripheral blood of 12 patients with chronic hepatitis C. It was demonstrated that the peptide-specific response of CD4+ T cells was restricted to the presence of autologous accessory cells and HLA-DR and -DP molecules. Eight peptide-specific T cell lines and five T cell clones derived from liver tissue and peripheral blood, released interferon-gamma (200-6600 pg/ml) and tumor necrosis factor-alpha (100-400 pg/ml) and no or little interleukin-4 (< 140 pg/ml) after peptide-specific or mitogeneic stimulation, thus resembling a Th1-like cytokine profile. Patients with active liver disease showed significantly higher proliferative responses to hepatitis C virus core peptides than asymptomatic hepatitis C virus carriers or complete responders to interferon therapy. In conclusion, class II-restricted CD4+ T cell responses to some immunodominant epitopes within the hepatitis core region correlated with disease activity in chronic hepatitis C virus infection. Functionally, liver-infiltrating and peripheral blood T cells released Th1-like cytokines in response to the specific stimulus. Thus, it can be suggested that CD4+ T cells can mediate the pathogenesis of chronic hepatitis C virus induced liver disease.
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PMID:Liver-infiltrating and circulating CD4+ T cells in chronic hepatitis C: immunodominant epitopes, HLA-restriction and functional significance. 887 4

Peripheral blood mononuclear cells (PBMC) of patients with autoimmune hepatitis (AIH) and controls were studied for their proliferative response to six overlapping synthetic peptides covering the 33-amino acid immunodominant region of cytochrome P450IID6, the main target antigen of LKM-1 antibody-positive type II AIH. PBMC from 8 of 8 type II AIH patients (100%), 6 of 12 LKM-1 antibody-negative type I AIH patients (50%), but only 4 of 31 patients with chronic hepatitis C (12.9%) reacted with a 23-amino acid LKM peptide and mainly with a shorter 18-amino acid LKM peptide. Follow-up showed that LKM-specific T-cell responses decreased after immunosuppression had started. Fine specificity, HLA restriction, and cytokine release of LKM-specific T cells were analyzed with 16 CD4+ peptide-specific T-cell lines and 21 CD4+ T-cell clones isolated and expanded from blood and liver tissue of six AIH patients. Activated LKM-specific T cells released interferon gamma (IFN-gamma) but no or little interleukin-4. In three AIH patients, PBMC showed specific recognition of autologous LKM-specific T cells, suggesting the presence of a regulatory T-cell network. These T cells also showed the CD4+ phenotype and secreted large amounts of IFN-gamma. Furthermore, it was assessed that the regulatory T-cell response is clonotypic. To conclude, we describe a major T-cell epitope in AIH that was recognized by Th1 helper cells isolated from blood and liver tissue. This autoreactive T-cell response correlated widely with disease activity and LKM-1 antibody status and seemed to be regulated by anticlonotypic T cells.
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PMID:Autoreactive CD4+ LKM-specific and anticlonotypic T-cell responses in LKM-1 antibody-positive autoimmune hepatitis. 893 73

There is a growing body of evidence to suggest that cytokines may be involved in the aetiology of alcoholic hepatitis. To study the effects of chronic ethanol feeding on cytokine production we have maintained rats on the control and ethanol-containing forms of the Lieber-DeCarli liquid diet for six weeks. The animals were then given an i.v. injection of endotoxin to induce hepatitis. It was found that the ethanol-fed animals had biochemical and histological evidence of mild to severe liver damage whereas control-fed animals had minimal liver damage. When plasma levels of cytokines were measured, it was found that the ethanol-fed rats produced much higher levels of tumour necrosis factor and interleukin 6 bioactivity than the control-fed rats. However, elevated levels of interleukin 1 protein were not seen in the ethanol-fed animals.
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PMID:The effect of chronic ethanol feeding on cytokines in a rat model of alcoholic liver disease. 897 67

TNF-alpha is a pleiotropic cytokine that exists both as a 26-kDa cell-associated and a 17-kDa soluble form. Recently, a class of matrix metalloproteinase inhibitors has been identified that can prevent the processing by TNF convertase of 26-kDa TNF-alpha to its 17-kDa form and can reduce mortality from normally lethal doses of D-galactosamine plus LPS (D-GalN/LPS). Here we report that a matrix metalloproteinase inhibitor, GM-6001, improves survival but does not protect against liver injury from D-GalN/LPS-induced shock in the mouse. In Con A-induced hepatitis, GM-6001 actually exacerbates hepatocellular necrosis and apoptosis despite greater than 90% reduction in plasma TNF-alpha concentrations. Treatment with GM-6001 also has minimal effect on the concentration of membrane-associated TNF-alpha in the livers of animals with Con A induced hepatitis. In contrast, a TNF binding protein (TNF-bp), which neutralizes both membrane-associated and soluble TNF-alpha, prevents D-GalN/LPS- and Con A-induced hepatitis. Our studies suggest that cell-associated TNF-alpha plays a role in the hepatocellular necrosis and apoptosis that accompany D-GalN/LPS- or Con A-induced hepatitis, and that matrix metalloproteinase inhibitors are ineffective in preventing this hepatic injury.
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PMID:Involvement of 26-kDa cell-associated TNF-alpha in experimental hepatitis and exacerbation of liver injury with a matrix metalloproteinase inhibitor. 897 17

To investigate the relationship between intrahepatic cytokine expression and interferon (IFN) response in chronic hepatitis C [CH(C)], interleukin (IL)-1 beta, -2, -4, -6, -8, interferon (IFN)-gamma, tumor necrosis factor (TNF)-alpha and TNF-beta mRNAs were investigated semiquantitatively by reverse transcription polymerase chain reaction using serial liver biopsies taken before and after IFN-alpha treatment from 24 patients with CH(C), including 12 responders and 12 non-responders. Before IFN treatment, IL-2, TNF-beta, IFN-gamma and IL-8 mRNA were associated with severe hepatitis activity whereas IL-4 mRNA was associated with weak hepatitis activity, regardless of IFN response. IL-2, TNF-beta and IFN-gamma mRNAs were significantly greater in IFN non-responders. After IFN treatment a complete response to IFN was significantly associated with the disappearance of these pro-inflammatory cytokines, whereas non-responders retained the expression of cytokine mRNA as before IFN treatment. Our results indicated that IFN-alpha treatment may modulate the intrahepatic cytokine network, and this may be one mechanism of IFN-alpha that reduces hepatitis activity, aside from an anti-viral effect. A difference in cytokine network may be involved in IFN response in CH(C).
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PMID:Intrahepatic expression of pro-inflammatory cytokine mRNAs and interferon efficacy in chronic hepatitis C. 902 19

A 17-year-old female patient who had been taking oral minocycline (50 mg twice daily) for 3 weeks for acne developed an eruption that progressed to an exfoliative dermatitis. This illness was also characterized by fever, lymphadenopathy, pharyngitis, a leukemoid reaction, lymphocytosis, eosinophilia, hepatitis, and noncardiogenic pulmonary edema. Dramatic improvement followed institution of corticosteroid therapy. Studies for infectious and collagen vascular diseases were negative. This severe illness was likely caused by minocycline, and we speculate that minocycline may have acted as a superantigen, causing lymphocyte over-activation and massive cytokine release.
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PMID:Fever, lymphadenopathy, eosinophilia, lymphocytosis, hepatitis, and dermatitis: a severe adverse reaction to minocycline. 944 27

C-X-C chemokines are potent chemoattractants that are believed to mediate neutrophilic inflammation in several organs. Recent studies suggest a role for C-X-C chemokines in the pathogenesis of neutrophilic hepatitis but do not prove causation. We investigated the biological consequences of hepatic chemokine production in vivo by transiently overexpressing cytokine-induced neutrophil chemoattractant (CINC), a member of the C-X-C chemokine family, in intact rats. Rats were injected intraportally with a replication-defective recombinant adenovirus containing the CINC complementary DNA (cDNA). Within 4 days, treated animals had high levels of CINC in both liver tissue and plasma Rats overexpressing CINC exhibited an eightfold increase in circulating neutrophils; they also developed severe hepatic injury, characterized by a 6- to 25-fold increase in plasma transaminases and marked hepatic inflammation on biopsy. Liver disease in CINC-producing rats correlated positively with the number of neutrophils sequestered in the hepatic parenchyma. Tissue injury was attributed directly to chemokine overproduction, because control rats infected with adenoviruses lacking the CINC cDNA did not produce CINC and developed only minor hepatic abnormalities. These experiments provide direct evidence that C-X-C chemokines, when expressed in sufficient quantity in the liver in vivo, induce neutrophil recruitment and tissue invasion and provoke severe liver injury. The data suggest that C-X-C chemokines have important pathogenic potential in both clinical and experimental liver disease.
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PMID:Adenovirus-mediated expression of cytokine-induced neutrophil chemoattractant in rat liver induces a neutrophilic hepatitis. 904 9

Recombinant human IL-4 (rhuIL-4) has been evaluated in a series of preclinical studies. These studies have demonstrated that rhuIL-4 is a very potent cytokine with a wide range of pharmacologic and toxicologic effects. Target systems/organs included the cardiovascular system, liver, spleen, and bone marrow. The incidence and severity of effects correlated strongly with both the dose level and the duration of rhuIL-4 administration. The major dose-limiting toxicities identified included death, cardiac inflammation and necrosis, hepatitis, and hepatic necrosis and occurred at sc doses > or = 25 micrograms/kg/day, while a sc dose of 5 micrograms/kg/day was the highest tested that did not result in major dose-limiting toxicity. Clinical trials in humans have demonstrated that sc administration of Escherichia coli-derived rhuIL-4 is safe and well tolerated at doses up to and including 5 micrograms/kg/day and up to 10 micrograms/kg when administered 3 times/week.
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PMID:Safety evaluation of recombinant human interleukin-4. I. Preclinical studies. 907 26

The cytokine pattern secreted by T cells on viral antigen recognition is believed to exert a profound influence on both the type of disease caused by the infecting agent and the final outcome of the viral infection. To characterize the cytokine pattern associated with spontaneous resolution of acute hepatitis B, we analyzed interferon gamma (IFN-gamma), interleukin (IL)-4, and IL-5 production by a wide series of hepatitis B virus (HBV) nucleocapsid-specific T-cell lines (34 lines) and T-cell clones (71 clones) derived from the peripheral blood of 13 patients during the acute or recovery phase of hepatitis B (2 and 7 of them were studied only in the recovery or the acute phase, respectively, and 4 during both). Most T-cell lines (67%) and clones (77%) isolated during the acute phase of infection expressed a T-helper (Th) 1 cytokine profile dominated by the production of IFN-gamma. A larger proportion (74%) of T-cell lines produced several years after resolution of hepatitis was able to secrete not only IFN-gamma, but also IL-4 and IL-5 (Th0-like cells). Results indicate that the antigen-specific fraction of peripheral blood T cells in acute self-limited hepatitis B selectively secrete Th1-type eytokines, suggesting that Th1-mediated effects may contribute not only to liver cell injury, but probably also to recovery from disease and successful control of infection.
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PMID:Predominant T-helper 1 cytokine profile of hepatitis B virus nucleocapsid-specific T cells in acute self-limited hepatitis B. 909 14

Human natural immunoglobulin (HunIg) preparation for intravenous use has been used in various diseases. The most typical application of this preparation is agammaglobulinemia. Currently, however, this preparation is being used in the therapy of many other disorders. These include thrombocytopenia, Kawasaki disease, systemic vasculitis, several other disorders of autoimmune origin and systemic inflammation such as sepsis. In some diseases, the clinical improvement following use of HunIg has been dramatic, while in others its effect is not striking. Due to rarity of the side effects, the range of application of HunIg has been recently broadened. Such side effects include transmission of several diseases such as hepatitis and retroviral infections. Before it is recommended for use, however, and primarily due to expense, the efficacy of this drug should be carefully evaluated. The mechanism of action of HunIg is not fully understood. However, it has been suggested that its action may involve blockade of Fc-receptor, an anti-cytokine effect, or inhibition of complement activation. In this review, the mechanism of action of HunIgG and its application in human diseases are discussed.
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PMID:Therapeutic application of intravenous human natural immunoglobulin preparation. 915 42


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