scholarly journals Gamma Interferon and Lipopolysaccharide Interact at the Level of Transcription To Induce Tumor Necrosis Factor Alpha Expression

2001 ◽  
Vol 69 (5) ◽  
pp. 2847-2852 ◽  
Author(s):  
Julia Y. Lee ◽  
Kathleen E. Sullivan

ABSTRACT Lipopolysaccharide (LPS) is a very potent inducer of tumor necrosis factor alpha (TNF-α) expression from monocytes and macrophages. Another inflammatory cytokine, gamma interferon (IFN-γ), can potentiate the effects of LPS, but the mechanism is not thoroughly understood. Previous reports emphasized the ability of IFN-γ to upregulate CD14 expression (the receptor for LPS), and nearly all studies have utilized sequential stimulation with IFN-γ followed by LPS to exploit this phenomenon. This study demonstrates that IFN-γ can upregulate the effect of LPS at the level of transcription. Human monoblastic Mono-Mac-6 cells produced up to threefold-greater levels of TNF-α when simultaneously stimulated with LPS and IFN-γ compared to treatment with LPS alone. RNase protection studies showed a similar increase in RNA beginning as early as within 30 min. The synthesis of TNF-α mRNA in IFN-γ- and LPS-treated Mono-Mac-6 cells was also temporally prolonged even though the message turnover rate was identical to that seen in LPS stimulated cells. The modulatory effect of IFN-γ may be mediated by Jak2.

2010 ◽  
Vol 18 (1) ◽  
pp. 95-104 ◽  
Author(s):  
Danielle Freches ◽  
Marta Romano ◽  
Hannelie Korf ◽  
Jean-Christophe Renauld ◽  
Jacques Van Snick ◽  
...  

ABSTRACTInterleukin-12 (IL-12) and IL-23 (which share a p40 subunit) are pivotal cytokines in the generation of protective Th1/Th17-type immune responses upon infection with the intracellular pathogenMycobacterium tuberculosis. The role of IL-12 and IL-23 in protection conferred by the tuberculosis vaccineMycobacterium bovisbacillus Calmette-Guérin (BCG) is, however, less well documented. By using an autovaccine approach, i.e., IL-12p70 cross-linked with ovalbumin and PADRE peptide formulated with the GSK proprietary adjuvant system AS02V, we could specifically neutralize IL-12 while leaving the IL-23 axis intact. Neutralization of IL-12 beforeM. tuberculosischallenge rendered C57BL/6 mice highly susceptible, resulting in 30-fold-higher CFU in spleen and lungs and accelerated mortality. In contrast, neutralization of IL-12 in BCG-vaccinated mice prior toM. tuberculosischallenge only marginally affected vaccine-mediated protection. Analysis of cytokine production in spleen and lungs 3 weeks post-TB challenge by enzyme-linked immunosorbent assay and functional and flow cytometric assays showed significantly reduced mycobacterium-specific gamma interferon (IFN-γ) responses inM. tuberculosis-infected and BCG-vaccinated mice that had been treated with the autovaccine. Purified protein derivative-induced tumor necrosis factor alpha (TNF-α), IL-6, and IL-17A levels, however, were highest in lungs from BCG-vaccinated/IL-12-neutralized animals, and even unstimulated lung cells from these mice produced significant levels of the three cytokines. Mycobacterium-specific IL-4 and IL-5 production levels were overall very low, but IL-12 neutralization resulted in increased concanavalin A-triggered polyclonal secretion of these Th2-type cytokines. These results suggest that TNF-α, IL-6, and IL-17A may be more important pulmonary effector molecules of BCG-mediated protection than IFN-γ in a context of IL-12 deficiency.


2003 ◽  
Vol 10 (1) ◽  
pp. 44-52 ◽  
Author(s):  
John A. Christopherson ◽  
Erik L. Munson ◽  
Douglas M. England ◽  
Cindy L. Croke ◽  
Monica C. Remington ◽  
...  

ABSTRACT We found that Borrelia burgdorferi-vaccinated gamma interferon-deficient (IFN-γ0) mice challenged with B. burgdorferi developed prominent chronic destructive osteoarthropathy. When these mice were treated with anti-tumor necrosis factor alpha (TNF-α) antibody, the severity of the destructive osteoarthritis was enhanced and affected the mobility of the animals. In addition, extensive swelling of the hind paws occurred. In contrast, treatment of B. burgdorferi-vaccinated, challenged IFN-γ0 mice with recombinant TNF-α (rTNF-α) inhibited the development of arthritis, including swelling of the hind paws. Moreover, treatment of vaccinated, challenged IFN-γ0 mice with anti-TNF-α inhibited fourfold the production of an antibody that kills B. burgdorferi, while treatment of vaccinated, challenged IFN-γ0 mice with rTNF-α slightly elevated the level of the borreliacidal antibody. These results suggest that the level of TNF-α directly or indirectly regulates the production of borreliacidal antibody and the development of vaccine-induced destructive Lyme osteoarthritis. Studies are in progress to determine the mechanism by which TNF-α-dependent cytokines generate the destructive arthritis.


2001 ◽  
Vol 69 (11) ◽  
pp. 6580-6587 ◽  
Author(s):  
Jan Warwick-Davies ◽  
Amanda J. Watson ◽  
George E. Griffin ◽  
Sanjeev Krishna ◽  
Robin J. Shattock

ABSTRACT Mycobacterium tuberculosis alone induces small, donor-variable amounts of tumor necrosis factor alpha (TNF-α) from primary human monocytes in vitro. However, TNF-α release is increased 5- to 500-fold when fixed activated T cells (FAT) or their isolated, unfixed membranes are added to this system. This FAT-induced synergy was at least as potent as that induced by gamma interferon (IFN-γ) at 100 U/ml. FAT-enhanced TNF-α production is at least in part transcriptionally mediated, as reflected by quantitative changes in TNF-α mRNA between 2 and 6 h poststimulation. Unlike IFN-γ-cocultured cells, FAT-treated monocytes appeared not to have enhanced TNF-α message stability, suggesting that de novo transcription may be involved in this effect. Furthermore, M. tuberculosis alone induced only minimal DNA binding of monocyte NF-κB, but cells treated with M. tuberculosis and FAT potentiated NF-κB activity more effectively. It is therefore possible that one mechanism by which FAT synergize with M. tuberculosis to stimulate TNF-α production is via NF-κB-enhanced transcription. These data strongly suggest that in the interaction of cells involved in the immune response to M. tuberculosis, T-cell stimulation of monocyte TNF-α production involves a surface membrane interaction(s) as well as soluble mediators.


2003 ◽  
Vol 71 (1) ◽  
pp. 267-270 ◽  
Author(s):  
Stephen J. Rogerson ◽  
Heidi C. Brown ◽  
Elena Pollina ◽  
Elizabeth T. Abrams ◽  
Eyob Tadesse ◽  
...  

ABSTRACT Malaria in pregnancy predisposes to maternal anemia and low birth weight (LBW). We examined the possible roles of the cytokines tumor necrosis factor alpha (TNF-α) and gamma interferon (IFN-γ) in these adverse outcomes. We measured cytokine concentrations in placental, peripheral, and cord blood plasma in relation to malaria parasitemia and placental monocyte accumulation in 276 Malawian women. Maternal hemoglobin concentration, human immunodeficiency virus status, and infant birth weight were determined. Concentrations of TNF-α in placental blood were correlated with densities of Plasmodium falciparum-infected erythrocytes (P < 0.0001) and of intervillous monocyte infiltrates (P < 0.0001) on placental histology. Peripheral blood TNF-α concentrations were relatively low and were weakly associated with malaria. TNF-α concentrations were higher in placental blood, where they were strongly associated with malaria. Placental plasma TNF-α levels were higher in women who had LBW babies (P = 0.0027), women with febrile symptoms (P < 0.0001), and teenage mothers (P = 0.04) than in other women. The presence of TNF-α in cord blood was not associated with malaria infection. IFN-γ levels were infrequently elevated, and elevated IFN-γ levels were not associated with poor pregnancy outcomes. Placental production of TNF-α, but not of IFN-γ, may be implicated in impaired fetal growth in Malawian women.


2002 ◽  
Vol 70 (4) ◽  
pp. 2082-2089 ◽  
Author(s):  
Sherilyn Smith ◽  
Denny Liggitt ◽  
Elizabeth Jeromsky ◽  
Xiaoxia Tan ◽  
Shawn J. Skerrett ◽  
...  

ABSTRACT The local intrapulmonary role of tumor necrosis factor alpha (TNF-α) in a protective host response during acute and chronic infection with Mycobacterium tuberculosis is incompletely understood. To directly assess its role in the intrapulmonary immune response, we compared the responses of transgenic mice with a local pulmonary blockade of TNF-α (SPCTNFRIIFc mice) to mice with globally inhibited TNF-α (TNFRKO mice) and mice with normal immune systems (control mice). Consistent with previous reports, 100% of TNFRKO mice died by 28 days after aerosol infection, and these mice had markedly increased numbers of bacteria and widespread tissue necrosis in their lungs compared to controls. The median survival time of the SPCTNFRIIFc mice was 142 days, and 75% died by 180 days. Even though the numbers of bacteria in the lungs of the SPCTNFRIIFc mice were marginally increased compared to controls, these mice had a persistent neutrophilic inflammatory response and increased expression of proinflammatory cytokines (interleukin-1α/β [IL-1α/β], IL-18, gamma interferon, IL-6, and macrophage migration inhibitory factor) and chemokines (eotaxin, macrophage inflammatory protein 1α/β, gamma interferon-inducible protein 10, macrophage chemotaxic protein 1, and TCA-3) in their lungs. These studies with the SPCTNFRIIFc mice provide direct evidence for the local importance of TNF-α in the proper regulation of host defense to M. tuberculosis. The studies also suggest that when the local actions of TNF-α are selectively impaired in the lungs, tissue destruction and death ensue, at least in part, due to persistent expression of proinflammatory mediators that would normally be downregulated.


2011 ◽  
Vol 44 (13) ◽  
pp. S298
Author(s):  
Faryabi Mohamad Reza ◽  
Kamali-Sarvestani Eskandar ◽  
Namian Ali-Mohammad ◽  
Shahbaz Shima ◽  
Salmanpoor Rahmatolah

1999 ◽  
Vol 67 (1) ◽  
pp. 206-212 ◽  
Author(s):  
Thomas K. Held ◽  
Xiao Weihua ◽  
Liang Yuan ◽  
Dhananjaya V. Kalvakolanu ◽  
Alan S. Cross

ABSTRACT When given in the presence of gamma interferon (IFN-γ), otherwise nontoxic doses of lipopolysaccharide (LPS or endotoxin) become highly lethal for mice. The mechanisms of this synergistic toxicity are not known. We considered the possibility that an interaction between the LPS-induced NF-κB and IFN-γ-induced JAK-STAT pathways at the pretranscriptional level may enhance the LPS-induced signals. To test this hypothesis, we incubated murine macrophage RAW 264.7 cells with IFN-γ for 2 h before addition of different doses of LPS. Consistent with the synergistic induction of inducible nitric oxide synthase mRNA and nitric oxide production by a combination of LPS and IFN-γ, IFN-γ strongly augmented LPS-induced NF-κB activation and accelerated the binding of NF-κB to DNA to as early as 5 min. In agreement with this, IFN-γ pretreatment promoted rapid degradation of IκB-α but not that of IκB-β. Inhibition of protein synthesis during IFN-γ treatment suppressed LPS-initiated NF-κB binding. A rapidly induced protein appeared to be involved in IFN-γ priming. Preincubation of cells with antibodies to tumor necrosis factor alpha or the interleukin-1 receptor partially reduced the priming effect of IFN-γ. In a complementary manner, LPS enhanced the activation of signal-transducing activator of transcription 1 by IFN-γ. These data suggest novel mechanisms for the synergy between IFN-γ and LPS by which they cross-regulate the signal-transducing molecules. Through this mechanism, IFN-γ may transform a given dose of LPS into a lethal stimulus capable of causing sepsis. It may also serve a beneficial purpose by enabling the host to respond quickly to relatively low doses of LPS and thereby activating antibacterial defenses.


2000 ◽  
Vol 68 (7) ◽  
pp. 4075-4083 ◽  
Author(s):  
Christoph Hölscher ◽  
Markus Mohrs ◽  
Wen Juan Dai ◽  
Gabriele Köhler ◽  
Bernhard Ryffel ◽  
...  

ABSTRACT Using interleukin-10 (IL-10)-deficient (IL-10−/−) mice, previous studies revealed a pathological immune response after infection with Trypanosoma cruzi that is associated with CD4+ T cells and overproduction of proinflammatory cytokines. In this study we further investigate the pathology and potential mediators for the mortality in infected animals. T. cruzi-infected IL-10−/− mice showed reduced parasitemia accompanied by increased systemic release of gamma interferon (IFN-γ), IL-12, and reactive nitrogen intermediates and overproduction of tumor necrosis factor alpha (TNF-α). Despite this early resistance, IL-10−/− mice died within the third week of infection, whereas all control mice survived acute infection. The clinical manifestation with weight loss, hypothermia, hypoglycemia, hyperkalemia, and increased liver-derived enzymes in the blood together with hepatic necrosis and intravascular coagulation in moribund mice indicated a toxic shock-like syndrome, possibly mediated by the systemic TNF-α overproduction. Indeed, high production of systemic TNF-α significantly correlated with mortality, and moribund mice died with critically high TNF-α concentrations in the blood. Consequent treatment with anti-TNF-α antiserum attenuated pathological changes in T. cruzi-infected IL-10−/− mice and significantly prolonged survival; the mice died during the fourth week postinfection, again with a striking correlation between regaining high systemic TNF-α concentrations and the time of death. Since elevated serum IL-12 and IFN-γ concentrations were not affected by the administration of antiserum, these studies suggest that TNF-α is the direct mediator of this toxic shock syndrome. In conclusion, induction of endogenous IL-10 during experimentally induced Chagas' disease seems to be crucial for counterregulating an overshooting proinflammatory cytokine response resulting in TNF-α-mediated toxic shock.


2000 ◽  
Vol 68 (5) ◽  
pp. 2827-2836 ◽  
Author(s):  
Gael Fenhalls ◽  
Anthony Wong ◽  
Juanita Bezuidenhout ◽  
Paul van Helden ◽  
Philip Bardin ◽  
...  

ABSTRACT Human tuberculous granulomas from five adults undergoing surgery for hemoptysis were analyzed by nonradioactive in situ hybridization for tumor necrosis factor alpha (TNF-α), gamma interferon (IFN-γ), and interleukin-4 (IL-4) gene expression. All of the patients produced TNF-α mRNA. Three patients stained positive for both IFN-γ and IL-4 mRNA; the other two stained positive for IFN-γ but not IL-4 mRNA. Heterogeneity between the granulomas was observed in those patients staining positive for both IFN-γ and IL-4 mRNA; these patients exhibited granulomas having IFN-γ and not IL-4 mRNA as well as granulomas positive for both cytokine mRNAs. There was no evidence of caseation in these granulomas, and the cytokine patterns may represent events in the evolution of the granuloma. However, in those granulomas exhibiting caseous necrosis, very little IFN-γ or IL-4 mRNA was observed, implying that progression of the granuloma is accompanied by a down regulation of T-cell responses. TNF-α mRNA expression was highest in patients with both IFN-γ and IL-4 mRNA. Populations of CD68 positive macrophage-like cells within the granulomas produce mRNA for TNF-α, IFN-γ, and IL-4. This implies that macrophages within the tuberculous granuloma may not be dependent on T-cell cytokines for modulation of their function but may be able to regulate their own activation state and that of the surrounding T cells. These findings have implications on the delivery of immunotherapies to patients with tuberculosis.


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