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)

Inoculation of mice with most neurotropic strains of the coronavirus mouse hepatitis virus results in an immune response-mediated demyelinating disease that serves as an excellent animal model for the human disease multiple sclerosis. Recent work has shown that either virus-specific CD4(+) or CD8(+) T cells are able to mediate demyelination and also that the antibody response is crucial for clearing infectious virus. Another exciting advance is the development of recombinant coronaviruses, which, for the first time, will allow genetic manipulation of the entire viral genome.
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PMID:Mouse hepatitis virus. 1149 12

In the present study, we evaluated the role of CCR2 in a model of viral-induced neurologic disease. An orchestrated expression of chemokines, including the CCR2 ligands monocyte chemoattractant protein-1/CCL2 and monocyte chemoattractant protein-3/CCL7, occurs within the CNS following infection with mouse hepatitis virus (MHV). Infection of mice lacking CCR2 (CCR2(-/-)) with MHV resulted in increased mortality and enhanced viral recovery from the brain that correlated with reduced (p < or = 0.04) T cell and macrophage/microglial (determined by F4/80 Ag expression, p < or = 0.004) infiltration into the CNS. Moreover, MHV-infected CCR2(-/-) mice displayed a significant decrease in Th1-associated factors IFN-gamma (p < or = 0.001) and RANTES/CCL5 (p < or = 0.002) within the CNS as compared with CCR2(+/+) mice. Further, peripheral CD4(+) and CD8(+) T cells from immunized CCR2(-/-) mice displayed a marked reduction in IFN-gamma production in response to viral Ag and did not migrate into the CNS of MHV-infected recombination-activating gene (RAG)1(-/-) mice following adoptive transfer. In addition, macrophage/microglial infiltration into the CNS of RAG1(-/-) mice receiving CCR2(-/-) splenocytes was reduced (p < or = 0.05), which correlated with a reduction in the severity of demyelination (p < or = 0.001) as compared with RAG1(-/-) mice receiving splenocytes from CCR2(+/+) mice. Collectively, these results indicate an important role for CCR2 in host defense and disease by regulating leukocyte activation and trafficking.
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PMID:Lack of CCR2 results in increased mortality and impaired leukocyte activation and trafficking following infection of the central nervous system with a neurotropic coronavirus. 1159 87

Mouse hepatitis virus (MHV) provides an excellent animal model for the study of the immunopathological mechanisms involved in hepatic viral diseases. We previously generated an attenuated viral variant, YAC-MHV3, which induces a subclinical disease and recovery within 15 days. In contrast, the L2-MHV3 strain induces the development of a fulminant hepatitis, leading to death within 3 days. In this paper, we document intrahepatic and splenic T cell subpopulations involved in the hepatitis process and viral elimination identified in attenuated or pathogenic MHV3-infected C57BL/6 mice. Percentages of intrahepatic CD4(+) cells decreased in attenuated YAC-MHV3-infected mice, while they increased in mice infected with pathogenic L2-MHV3, compared with uninfected animals. Moreover, in YAC-MHV3-infected mice, the percentages of intrahepatic CD8(+) cells slightly decreased at 24 h pi, then increased until 15 days pi. In contrast, the CD4/CD8 ratios of splenic lymphoid subpopulations increased in the first days of infection and returned to normal values at 15 days pi. Intrahepatic NK1.1(+)alphabeta - TCR(inter) cells decreased in both virally infected groups of mice, while CD4(+)alphabeta - TCR(inter) LFA-1(high) cells increased in L2-MHV3-infected mice, in contrast with what was seen in YAC-MHV3-infected mice. However, these cells became anergic following Con A or PHA stimulation. Ex vivo studies showed that only the intrahepatic CD8(+) cells that were increased in YAC-MHV3-infected mice could be stimulated by lectins. In addition, in vitro viral infections revealed that L2-MHV3 viral infection led to an increase of intrahepatic CD4(+)alphabeta - TCR(inter) cells in the absence of CD8(+) cells only. These results indicate that the attenuated phenotype of the YAC-MHV3 virus is related to two different mechanisms: the first involves no increase of intrahepatic CD4(+)alphabeta - TCR(inter) or NK-T cells, while the second favors the recruitment and activation of CD8(+) cells in liver. The results are discussed in relation to the integrity of intrahepatic immune tolerance mechanisms and immune-mediated viral elimination.
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PMID:Recovery from mouse hepatitis virus infection depends on recruitment of CD8(+) cells rather than activation of intrahepatic CD4(+)alphabeta(-)TCR(inter) or NK-T cells. 1172 27

Mice infected with the murine coronavirus, mouse hepatitis virus, strain JHM (MHV) develop an immune-mediated demyelinating encephalomyelitis. We showed previously that adoptive transfer of MHV-immune splenocytes depleted of either CD4 or CD8 T cells to infected RAG1(-/-) recipients (mice deficient in recombination activation gene 1) resulted in demyelination. Herein we show that transfer of CD8 T cell-enriched splenocytes from MHV-immune IFN-gamma(-/-) donors resulted in a substantial decrease in demyelination (4.8% of the white matter of the spinal cord compared with 26.3% in those receiving cells from C57BL/6 donors). Similar numbers of lymphocytes were present in the CNS of recipients of either C57BL/6 or IFN-gamma(-/-) CD8 T cells, suggesting that IFN-gamma was not crucial for lymphocyte entry into the CNS. Rather, IFN-gamma was critical for optimal activation or migration of macrophages or microglia into the white matter in the context of CD8 T cell-mediated demyelination.
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PMID:Cutting edge: CD8 T cell-mediated demyelination is IFN-gamma dependent in mice infected with a neurotropic coronavirus. 1182 80

IFN-gamma-inducible protein 10 (IP-10, CXCL10), a chemokine secreted from cells stimulated with type I and II IFNs and LPS, is a chemoattractant for activated T cells. Expression of IP-10 is seen in many Th1-type inflammatory diseases, where it is thought to play an important role in recruiting activated T cells into sites of tissue inflammation. To determine the in vivo function of IP-10, we constructed an IP-10-deficient mouse (IP-10(-/-)) by targeted gene disruption. Immunological analysis revealed that IP-10(-/-) mice had impaired T cell responses. T cell proliferation to allogeneic and antigenic stimulation and IFN-gamma secretion in response to antigenic challenge were impaired in IP-10(-/-) mice. In addition, IP-10(-/-) mice exhibited an impaired contact hypersensitivity response, characterized by decreased ear swelling and reduced inflammatory cell infiltrates. T cells recovered from draining lymph nodes also had a decreased proliferative response to Ag restimulation. Furthermore, IP-10(-/-) mice infected with a neurotropic mouse hepatitis virus had an impaired ability to control viral replication in the brain. This was associated with decreased recruitment of CD4(+) and CD8(+) lymphocytes into the brain, reduced levels of IFN-gamma and the IFN-gamma-induced chemokines monokine induced by IFN-gamma (Mig, CXCL9) and IFN-inducible T cell alpha chemoattractant (I-TAC, CXCL11) in the brain, decreased numbers of virus-specific IFN-gamma-secreting CD8(+) cells in the spleen, and reduced levels of demyelination in the CNS. Taken together, our data suggest a role for IP-10 in both effector T cell generation and trafficking in vivo.
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PMID:IFN-gamma-inducible protein 10 (IP-10; CXCL10)-deficient mice reveal a role for IP-10 in effector T cell generation and trafficking. 1190 72

Subpopulation of cytotoxic lymphocytes CD8 having both secretory and cytolytic antiviral activity is supposed to play the essential role in the virus elimination. Inflammatory reactions are also of importance in the hepatitis C pathogenesis, their intensity being regulated by anti-inflammatory cytokins. This study was aimed at determination of lymphocyte subpopulation indices--the relative content of cells carrying markers CD4, CD8, CD16, CD19, CD72, the parameters of the phagocytic activity of granulocytes and monocytes, as well as serum concentrations of anti-inflammatory cytokines IL-1, IL-6 and TNF-alpha. These indices were evaluated in a group 132 patients with confirmed hepatitis C or mixed hepatitis B + C diagnosis, depending on the disease form and markers of the infectious process activity (as determined in the PCR test for hepatitis C virus RNA) in comparison with a group of healthy donors. In patients with variant hepatitis under study a growth in anti-inflammatory mediators concentration was observed along with decreased indices of lymphocyte subpopulations responsible for cell-mediated immunity and the phagocytosis parameters. In the case of mixed hepatitis these differences were shown to be more manifested.
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PMID:[Lymphocyte subpopulations and level of the proinflammatory cytokines in the blood of patients with hepatitis C and with combined variant of hepatitis C and B]. 1194 53

Previous work has shown that stimulation of APCs via CD40 strongly influences the outcome of a CD8 T cell response. In this study, we examined the effect of CD40 ligation on peripheral tolerance induction of self-reactive CD8 T cells in an adoptive transfer model. Naive CD8 T cells from TCR-transgenic (tg) mice specific for the gp33 epitope of lymphocytic choriomeningitis virus were tolerized when transferred into H8-tg mice expressing the gp33 epitope under the control of a MHC class I promoter. However, if the H8 recipient mice were treated with agonistic anti-CD40 Abs, TCR-tg cells vigorously proliferated, and induced destruction of lymphoid organs and hepatitis. Break of peripheral tolerance induction was B cell independent and did not require CD28/B7 interactions. These findings provide further in vivo evidence for the crucial role of the activation state of the APC in peripheral tolerance induction and suggest the need for caution in systemically activating APC via CD40 ligation in the presence of self-reactive T cells.
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PMID:CD40 ligation in the presence of self-reactive CD8 T cells leads to severe immunopathology. 1199 66

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

Mice infected with the murine coronavirus, mouse hepatitis virus, strain JHM (MHV) develop an immune-mediated demyelinating encephalomyelitis. Adoptive transfer of MHV-immune splenocytes depleted of either CD4 or CD8 T cells to infected mice deficient in recombination activation gene 1 resulted in demyelination. We showed previously that the process of CD8 T-cell-mediated demyelination was strongly dependent on the expression of gamma interferon (IFN-gamma) by donor cells. In this report, we show, in contrast, that demyelination and lymphocyte infiltration were increased in recipients of IFN-gamma(-/-) CD4 T cells when compared to levels in mice receiving C57BL/6 CD4 T cells.
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PMID:CD4 T-cell-mediated demyelination is increased in the absence of gamma interferon in mice infected with mouse hepatitis virus. 1207 31

T cell recruitment to the infected liver is an essential step for the efficient elimination of hepatitis viruses. The surface expression of CC chemokine receptor (CCR) 1, CCR4, and CCR5 on peripheral blood T lymphocytes and their responsiveness to the chemokines macrophage inflammatory proteins (MIP)-1alpha, MIP-1beta, and RANTES (regulated on activation, normally T cell-expressed and secreted) was analyzed in patients with chronic hepatitis C and hepatitis B infection and compared with healthy subjects. Although CCR4 surface expression was not altered, hepatitis C virus (HCV)-infected patients had lower proportions of CD8 T cells with CCR1 and CCR5 surface expression (P<.05). Migration of CD8 T cells in response to MIP-1alpha, MIP-1beta, and RANTES was significantly reduced in HCV-infected patients (P<.05). Intracellular CCR1 and CCR5 protein and messenger RNA levels in peripheral blood T cells did not indicate reduced chemokine receptor biosynthesis in hepatitis C infection. Thus, chronic hepatitis C, but not hepatitis B, infection alters surface expression of distinct CCRs, resulting in lower CC chemokine responsiveness.
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PMID:Reduced CC chemokine receptor (CCR) 1 and CCR5 surface expression on peripheral blood T lymphocytes from patients with chronic hepatitis C infection. 1208 29


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