Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UNIPROT:P43026 (lipopolysaccharide)
 62,215 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Dithiocarbamates and iron chelators were recently considered for the treatment of AIDS and neurodegenerative diseases. In this study, we show that dithiocarbamates and metal chelators can potently block the activation of nuclear factor kappa B (NF-kappa B), a transcription factor involved in human immunodeficiency virus type 1 (HIV-1) expression, signaling, and immediate early gene activation during inflammatory processes. Using cell cultures, the pyrrolidine derivative of dithiocarbamate (PDTC) was investigated in detail. Micromolar amounts of PDTC reversibly suppressed the release of the inhibitory subunit I kappa B from the latent cytoplasmic form of NF-kappa B in cells treated with phorbol ester, interleukin 1, and tumor necrosis factor alpha. Other DNA binding activities and the induction of AP-1 by phorbol ester were not affected. The antioxidant PDTC also blocked the activation of NF-kappa B by bacterial lipopolysaccharide (LPS), suggesting a role of oxygen radicals in the intracellular signaling of LPS. This idea was supported by demonstrating that treatment of pre-B and B cells with LPS induced the production of O2- and H2O2. PDTC prevented specifically the kappa B-dependent transactivation of reporter genes under the control of the HIV-1 long terminal repeat and simian virus 40 enhancer. The results from this study lend further support to the idea that oxygen radicals play an important role in the activation of NF-kappa B and HIV-1.
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PMID:Dithiocarbamates as potent inhibitors of nuclear factor kappa B activation in intact cells. 131 83

A recent addition to the lymphokine network is human IL-10 (hIL-10). This novel lymphokine has striking homology to BCRF1 protein, the product of a previously uncharacterized open-reading frame in the Epstein-Barr virus (EBV) genome. To date, IL-10 expression has been described in several T clones induced with anti-CD3 and phorbol myristate acetate (PMA), in monocytes stimulated with lipopolysaccharide (LPS), and in murine B-cell lymphomas. We sought to determine whether human B cells express hIL-10 and, if so, its relationship to EBV and to other B-cell lymphokines. We studied 21 EBV-positive B-cell lines derived from patients with acquired immunodeficiency syndrome (AIDS) and Burkitt's lymphoma (n = 6), American Burkitt's (n = 3), African Burkitt's (n = 5), and normal lymphoblastoid cell lines (n = 7), in comparison with seven EBV-negative cell lines. All cell lines were activated with the tumor promoters PMA and teleocidin and were studied by Northern blot analysis, reverse transcription-polymerase chain reaction (RT-PCR), and enzyme-linked immunoadsorbent assay (ELISA). We demonstrated that EBV-positive cell lines derived from patients with American Burkitt's lymphoma, and especially those from patients with AIDS, constitutively express large quantities of hIL-10 by Northern blot analysis and ELISA (range, 3,101 to 25,915 pg/mL), and that both teleocidin and PMA induce hIL-10 in these cell lines. In contrast, six of seven EBV-negative cell lines did not express hIL-10 even by RT-PCR, and hIL-10 was not triggered by PMA or teleocidin. To assure that the 350 bp amplified by PCR was hIL-10 and not BCRF1, we used PCR primers, which do not amplify a fragment from plasmid templates containing BCRF1. Cloning and sequencing of the 350 bp product also demonstrated that B-cell IL-10 is identical to hIL-10 from the T-cell clone B21. Correlation of hIL-10 with other B-cell lymphokines secreted by these B-cell lines demonstrated that hIL-10 secretor cell lines also constitutively secrete or can be induced to secrete IL-6, although to a much lesser amount. Since both lymphokines influence B-cell growth and differentiation, we suggest that hIL-10 may contribute to the polyclonal B-cell activation and hyperglobulinemia seen in AIDS patients. Finally, several reports support the hypothesis that EBV is an important cofactor in the development of human immunodeficiency virus type 1 (HIV-1)-related B-cell lymphomas. Detection of large quantities of hIL-10 in B-cell lines derived from AIDS patients, the close association between EBV and hIL-10 shown in this report, and the ability of BCRF1 to capture hIL-10 activities, make hIL-10/BCRF1 an attractive candidate as a factor causing B-cell growth and immortalization in patients with AIDS and B-cell lymphomas.
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PMID:Human B-cell interleukin-10: B-cell lines derived from patients with acquired immunodeficiency syndrome and Burkitt's lymphoma constitutively secrete large quantities of interleukin-10. 842 93

The influence of mononuclear cell supernatants (MNCS) from nine healthy donors and 35 HIV-infected patients (17 with lymphoadenopathy syndrome (LAS), 15 with ARC and three with AIDS) on functional activity of polymorphonuclear neutrophils (PMN) from healthy donors was investigated. MNC after short-term cultivation (24 h) produced factors which enhanced chemiluminescence (CL) and chemotaxis of PMN. This augmentation did not depend on stimulation of MNC by mitogens (lipopolysaccharide Escherichia coli (LPS) and concanavalin A (Con A)) or on activation of PMN by FMLP. After 48 h of cultivation only MNC stimulated by LPS produced these factors. MNCS from HIV-infected patients provoked a more pronounced augmentation of PMN CL compared with MNCS from healthy subjects. This enhancement was observed in patients at all stages of infection, but was more pronounced in patients with LAS. MNCS impact on PMN CL was not connected with proliferative activity of MNC but was correlated with the level of CD4 cells. It was shown that removal of adherent cells from MNC fraction resulted in decreased MNCS impact. Treatment of MNCS by antibody to IL-1 beta, IL-8, interferon-alpha (IFN-alpha) and tumour necrosis factor-alpha (TNF-alpha) did not decrease MNCS impact on PMN CL.
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PMID:Mononuclear cells from HIV-infected patients produce factors which enhance functional activity of polymorphonuclear neutrophils from healthy subjects. 132 4

The effect of HIV infection on the production of tumor necrosis factor-alpha (TNF-alpha) was examined in patients with advanced human immunodeficiency virus (HIV) infection in the absence of AIDS-related secondary infections. Serum TNF-alpha and TNF-alpha production in vitro were measured by enzyme-linked immunosorbent assay in 26 male homosexuals with CDC stage IV HIV infection without active AIDS-related secondary infections. In vitro TNF-alpha production was assayed from cultured peripheral blood mononuclear cells (PBMs) or whole blood cultures under conditions for minimising endotoxin contamination. PBMs and whole blood were cultured with and without lipopolysaccharide (LPS). Results were compared with those for 13 HIV-seronegative age- and sex-matched controls. Serum TNF-alpha concentrations were 5 +/- 16 pg/ml in HIV-infected patients and 12 +/- 17 pg/ml in controls. TNF-alpha levels in unstimulated cultures of PBMs obtained from patients were 426 +/- 511 pg/ml and 456 +/- 428 pg/ml in control cultures. There was no difference between groups in the maximal responses of cultured PBMs to stimulation with LPS (2,229 +/- 1,593 pg/ml vs. 2,504 +/- 961 pg/ml). TNF-alpha levels from unstimulated and LPS-stimulated whole blood cultures were not significantly different after adjusting for the number of cultured monocytes (2,038 +/- 1,469 pg/ml vs. 1,511 +/- 488 pg/ml). In 10 patients (38%) the TNF-alpha levels from stimulated whole blood cultures were greater than the 95% confidence interval of the control group. TNF-alpha levels in patients were not significantly altered by antiretroviral therapy.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Tumor necrosis factor-alpha in advanced HIV infection in the absence of AIDS-related secondary infections. 145 35

Dimethylhydrazine (DMH) induces colonic cancer and angiosarcomas in mice. In order to determine pertinence of mouse angiosarcoma as a model to AIDS associated Kaposi's sarcoma (KS), we investigated if immune dysfunction occurred during tumor development by DMH. Outbred CD1 male mice received once weekly DMH a 20 mg/kg body weight dose s.c. for 33 weeks. Every two weeks initially and then every week groups of DMH-treated and control animals were sacrificed to determine a) peripheral blood and splenic T cell subset ratio b) 4-day plaque forming cell (PFC) response to i.p. sheep red blood cells (SRBC) and c) mitogenic response of spleen cells to Concanavalin A (Con A) and lipopolysaccharide (LPS). No change in T helper/T suppressor + cytotoxic T cell (Th/Tsupp. + CTL) and mitogenic response to spleen cells to Con A was noted whereas PFC response of animals to SRBC and mitogenic response of spleen cells to LPS decreased. These data suggest that either infection with T cell depleting virus such as LP:BM5 or immunosuppressive drugs affecting T cell function, such as steroids may be required to bring the immune status of DMH treated animals closer to that of AIDS associated KS bearing human subjects.
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PMID:An animal model of Kaposi's sarcoma. I. Immune status of CD1 mice undergoing dimethyl hydrazine treatment to induce angiosarcomas and other malignancies. 156 54

Macrophages and microglia are the principal target cells for human immunodeficiency virus (HIV) in brain, and as such, are likely participants in the neuropathology of HIV infection. In a model system for this process, we found that fluids from human monocyte cultures enhanced survival and differentiation of the neurons in fetal rat brain explants. In contrast, fluids from HIV-infected monocyte cultures were strongly toxic to neurons and paradoxically enhanced the proliferation of glial cells. Further, neuronotoxic activity in these fluids was mediated through activation of NMDA binding receptors on the neurons and was inhibited by any of several different NMDA antagonists. Neuronotoxic activity was directly related to contamination of the HIV virus stock with Mycoplasma arginini and M. hominis. Pure cultures of mycoplasma, bacterial lipopolysaccharide (LPS), or murine recombinant tumor necrosis factor alpha (rTNF alpha) each induced neuronotoxicity which exactly mirrored that induced by the contaminated HIV stock. It is likely that mycoplasma or components of the mycoplasma plasma membrane stimulate TNF alpha production by the glial cells in the brain explants. Indeed, careful depletion of glial cells in these explants prevented mycoplasma or LPS-mediated neuronotoxicity. No neuronotoxicity was evident with HIV-1 virus stock, HIV-1 gp120, or culture fluids from HIV-infected T cells or monocytes when these preparations were free of contamination by mycoplasma and LPS. These findings suggest caution in interpretation of those experiments in which similar contamination has not been rigorously excluded.
AIDS Res Hum Retroviruses 1992 Apr
PMID:No direct neuronotoxicity by HIV-1 virions or culture fluids from HIV-1-infected T cells or monocytes. 159 56

Tuberculosis is a major cause of mortality worldwide and incidence is increasing as a result of the AIDS epidemic. Cytokines such as tumor necrosis factor (TNF) are important in the host response to Mycobacterium tuberculosis. TNF is involved in both granuloma formation and has direct anti-mycobacterial activity. This study investigated the secretion of interleukin (IL)-8 following phagocytosis of M. tuberculosis by a human monocytic cell line and by a more phenotypically mature macrophage-like cell line. M. tuberculosis is shown to be a more potent inducer of IL-8 but not of TNF than bacterial lipopolysaccharide in vitro in both cell types. IL-8 production is partly a consequence of accumulation of mRNA coding for this cytokine. Secretion of IL-8 is not a simple consequence of the phagocytic process but due to the specific interaction M. tuberculosis and the monocyte. IL-8 production was independent of TNF and of virulence of the strain of M. tuberculosis. IL-8 secretion following phagocytosis of M. tuberculosis suggests that this cytokine may be involved in granuloma formation in vivo, possibly acting, in part, as a T cell chemoattractant.
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PMID:Secretion of interleukin-8 following phagocytosis of Mycobacterium tuberculosis by human monocyte cell lines. 160 Oct 32

Alveolar macrophages in AIDS patients have a marked increase in tumor necrosis factor release in active Pneumocystis carinii pneumonia. We have demonstrated that pentamidine, an aromatic diamidine currently used to treat AIDS-related P. carinii pneumonia, is an effective inhibitor of cellular tumor necrosis factor release from lipopolysaccharide-stimulated rat alveolar macrophages at concentrations greater than 10(-8) M. Inhibition of release is not dependent upon the continued presence of pentamidine in the culture medium during the release phase. In addition, this blockage occurs at neither the transcriptional level as determined by Northern blot analysis nor the translational level as determined by Western blot analysis. Timed addition studies suggest that pentamidine is targeting relatively early events following lipopolysaccharide administration. Pentamidine appears to alter early lipopolysaccharide-induced cellular processes associated with the release of tumor necrosis factor from macrophages.
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PMID:Modulation of tumor necrosis factor release from alveolar macrophages treated with pentamidine isethionate. 162 13

The effects of therapy with the immunomodulator diethyldithiocarbamate (DTC) on the manifestation and natural history of LP-BM5 murine retrovirus infection in adult C57 Black 6 mice was investigated. DTC itself, had limited effects on the spleen weight, serum IgM, or mitogen responses of the non-virus-infected control mice when evaluated over a 9-week period. The virus inoculum administered was such that there was approximately a twofold increase in serum IgM and a halving of phytohemagglutinin (PHA) and lipopolysaccharide (LPS) responses in about two weeks and death of all animals by about 26 weeks postinfection. Doses of DTC of 20 and 200 mg/kg weekly or 5 days per week (intraperitoneally) in mice with LP-BM5 infection did not alter the manifestations or course of the disease. Doses of 400 or 600 mg/kg given 5 days per week, starting either 2 weeks before or the day of virus inoculation significantly reduced hypergammaglobulinemia, spleen weight, lymphadenopathy, and also prolonged survival. A dose of 400 mg/kg started 2 weeks after virus inoculation resulted in partial prevention of hypergammaglobulinemia, splenomegaly, and lymphadenopathy as well as 100% survival compared with 12.5% in non-drug-treated controls at 23 weeks after virus inoculation. The 9 surviving animals in the treated group were then allocated to continue treatment or stop treatment. In the animals without further treatment, lymphadenopathy and mortality occurred starting within 6 weeks after cessation of therapy while the animals with continued treatment remained in good condition for 40 weeks. There was only a very limited and transient effect of DTC therapy on the decline of the proliferative responses to phytohemagglutinin or lipopolysaccharide in any of the treated groups in the above described experiments.(ABSTRACT TRUNCATED AT 250 WORDS)
AIDS Res Hum Retroviruses 1991 Jun
PMID:Effective therapy of the LP-BM5 murine retrovirus-induced lymphoproliferative immunodeficiency disease with diethyldithiocarbamate. 165 74

Treatment of mice with cyclophosphamide causes immunosuppression and an enhancement of murine cytomegalovirus infection. In chemotherapy experiments, animals received cyclophosphamide (100 mg/kg by intraperitoneal [ip] injection) every 3-4 days starting 1 day before viral challenge. Once-daily ip treatments with ganciclovir (12.5, 25, and 50 mg/kg) for 5 or 10 days starting 24 h after viral challenge delayed but did not prevent death. In each case the animals died 8-12 days after the last dose of drug was given. Murine cytomegalovirus titers in tissues were suppressed during ganciclovir treatments but rose with discontinuation of therapy. Concanavalin A (T cell blastogenic) responses and, to a lesser extent, lipopolysaccharide (B cell blastogenic) responses were increased in ganciclovir-treated mice compared with the placebo group. Because of the progressive nature of the infection after termination of drug treatment, this model mimics the situation encountered in AIDS patients. The cyclophosphamide model will be useful to study drug treatment regimens.
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PMID:Progressive murine cytomegalovirus disease after termination of ganciclovir therapy in mice immunosuppressed by cyclophosphamide treatment. 165 60


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