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)

The effects of Staphylococcus aureus enterotoxin A (SEA) and lipopolysaccharide (LPS) in cytokine production were assessed at the single cell level in cells obtained from healthy blood donors. Cytokine production was studied with UV-microscopy of fixed and permeabilized cells stained with cytokine specific monoclonal antibodies. The cytokines evaluated included tumour necrosis factor (TNF)-alpha, interleukin (IL)-1 alpha, IL-1 beta, IL-6, IL-8, IL-10, IL-2, IL-4, interferon (IFN)-gamma and TNF-beta. LPS exhibited marked production of IL-1 alpha, IL-1 beta, TNF-alpha, IL-6 and IL-8. After LPS stimulation IL-1 alpha, IL-1 beta, TNF-alpha and IL-8 were the dominating products, all peaking at or before 4 hours after cell stimulation. In addition, IL-10 production was evident after 12 hours of cell stimulation. The T-lymphocyte-derived cytokines TNF-beta, IL-2, IFN-gamma and IL-4 were never detected in the cultures. All cytokine production, except IL-8, was downregulated at 96 hours. In contrast, peak production of IL-1 alpha, IL-1 beta and IL-8, which were the dominant products, occurred after 12 hours in the SEA-stimulated cultures. Further, a significant T-lymphocyte production of TNF-beta, TNF-alpha, IFN-gamma and IL-2 was found with peak production 12-48 hours after initiation. Only low amounts of IL-6 were evident. The two types of cytokine pattern and kinetics found may correspond to the different clinical conditions after invasive Gram-negative Escherichia coli vs Gram-positive Staphylococcus aureus infections in humans, with a much more rapid onset of disease after E. coli infections.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Endotoxin and Staphylococcus aureus enterotoxin A induce different patterns of cytokines. 129 33

In vitro plasma perfusion experiments were performed using small columns containing either resin or charcoal adsorbents to assess the removal of cytokines and endotoxin. 125I-labelled tumor necrosis factor-alpha (TNF-alpha; 500 pg/ml) and interleukin-6 (IL-6; 10 ng/ml) were added individually to human plasma. Over 4 hr of perfusion, Amberlite XAD-7 resin removed 32.5% +/- 3.3% (n = 5) of the initial amount of TNF-alpha and 71.4% +/- 3.8% (n = 5) of the initial amount of IL-6. DHP-1 polyhema-coated activated charcoal removed 17.2% +/- 6.2% (n = 5) of TNF-alpha and 48.5% +/- 7.4% (n = 5) of IL-6. Preliminary experiments were performed with lipopolysaccharide (LPS; 100 ng/ml) and interleukin-1 alpha (IL-1 alpha; 500 pg/ml), which showed that, over 4 hr, Amberlite XAD-7 removed 10.3% of the initial LPS and 29.1% of IL-1 alpha, whereas DHP-1 charcoal removed 23.2% of the initial LPS and 65.3% of IL-1 alpha. In vitro plasma ultrafiltration with either polysulfone or polyacrylonitrile membranes, as used clinically in haemodialysis, was performed with recirculation of plasma containing LPS or TNF-alpha. Neither of the substances was filtered to a significant degree. In conclusion, direct removal of these inflammatory mediators from the circulation of patients with multiorgan failure due to fulminant hepatic failure or sepsis would be possible by perfusion of plasma through adsorbents but not by haemodialysis.
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PMID:In vitro plasma perfusion through adsorbents and plasma ultrafiltration to remove endotoxin and cytokines. 129 81

Fu-Ling, the sclederma of Poria cocos (Schw.) Wolf, has long been used as a sedative and diuretic. However, data in this report suggest that Fu-Ling is a potential suppressor of cytokine secretion from human peripheral blood monocytes under in vitro condition. Monocyte culture medium containing 10% of Fu-Ling extract significantly inhibited secretion of TNF-alpha, IL-beta, IL-6 and GM-CSF from the monocyte monolayer. However, as Fu-Ling extract content was gradually reduced, cytokine secretion was augmented in comparison with the cytokine secretion in drug-free controls. This augmentative effect resulted from the trace amount (1.24 ng/ml in 0.62% of Fu-Ling extract) of lipopolysaccharide (LPS) which contaminated the Fu-Ling extract during the preparation process, since TNF-alpha, IL-1 beta and IL-6 secretion induced by 0.62% Fu-Ling extract could be significantly inhibited by polymyxin B, an LPS inhibitor. Furthermore, the amounts of TNF-alpha IL-1 beta and IL-6 induced by 1 ng/ml of LPS without the presence of drug were more than that induced by 0.62% of Fu-Ling extract. Thus, cytokine secretion induced by LPS contamination (1.24 ng/ml) in the Fu-Ling extract was partially suppressed by 0.62% of the Fu-Ling extract itself. GM-CSF secretion in the medium containing 0.62% of Fu-Ling extract was not induced by LPS since: a) GM-CSF induced by 0.62% Fu-Ling extract could not be inhibited by polymyxin B; b) LPS at 1 ng/ml showed no activity indicating induction of GM-CSF secretion.
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PMID:Suppression of tumor necrosis factor-alpha, interleukin-1 beta, interleukin-6 and granulocyte-monocyte colony stimulating factor secretion from human monocytes by an extract of Poria cocos. 130 45

We examined the effect of lipopolysaccharide (LPS) on dextran bead-induced lung granulomas using LPS responder (C3H/HeN) and nonresponder (C3H/HeJ) mice. LPS augmented granuloma sizes, TNF-alpha and N-acetyl-beta-D-glucosaminidase levels of lung extracts in C3H/HeN, but not in C3H/HeJ mice. Granuloma macrophages of C3H/HeN mice produced higher levels of superoxide anion and TNF-alpha than those of C3H/HeJ mice. Taken together with our previous report that macrophages and macrophage-derived cytokines are essential for the development of lesions, the present results suggest that activation of macrophages plays an important role in the development and augmentation of pulmonary granulomas.
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PMID:Augmentation of pulmonary foreign body granulomatous inflammation in mice by lipopolysaccharide: involvement of macrophage activation and tumor necrosis factor-alpha. 131 16

Tumor necrosis factor (TNF), interleukin 1 (IL-1) and interleukin 6 (IL-6) are central mediators of the inflammatory response. We investigated the modulation of these cytokines by hormones in vitro. Murine adherent peritoneal exudate cells (PEC) were exposed to various concentrations of hormones followed by lipopolysaccharide (LPS, 10 micrograms/ml). TNF, IL-1 and IL-6 production were assessed by bioassays, enzyme-linked immunosorbent assays (ELISA) or Western blot, and specific RNA transcripts by Northern blot. Hydrocortisone in concentrations as low as 10 ng/ml had dramatic inhibitory effects on supernatant levels of TNF and IL-1 and on TNF, IL-1 and IL-6 transcript number. Supernatant levels of IL-6 were only slightly diminished by hydrocortisone. Adrenocorticotrophic hormone (ACTH) and insulin increased supernatant levels of TNF bioactivity in response to LPS, while each decreased available TNF-alpha gene transcripts. Thus TNF protein production was affected at a post-transcriptional level. ACTH and insulin increased supernatant levels of IL-6 produced in response to LPS without altering available transcripts. Corticotrophin-releasing factor (CRF), epinephrine and glucagon had no effect on supernatant levels of cytokine. Thus, physiological and pharmacological concentrations of hydrocortisone had dramatic inhibitory effects on the supernatant levels of TNF and IL-1, and on the number of available TNF, IL-1 and IL-6 transcripts in PEC exposed to LPS, but had minimal effects on supernatant levels of IL-6 bioactivity. This hydrocortisone action may be a specific negative feedback system for IL-1 and TNF, with relative sparing of IL-6.
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PMID:Hormonal regulation of inflammatory cell cytokine transcript and bioactivity production in response to endotoxin. 131 63

The mechanisms underlying the effects of alcohol (ethanol, ETOH) on host defense are poorly understood. ETOH modulation of the cytokine regulatory network is one possible way by which ETOH could alter nonspecific immune function. In this study we examined the ability of acute alcohol intoxication to alter lipopolysaccharide (LPS)-induced changes in tumor necrosis factor (TNF)-alpha binding to neutrophils and isolated liver plasma membranes. Rats were injected intravenously with a primed constant infusion of ETOH for 7 hr to maintain blood ETOH concentration at approximately 35 mM. Four hours after the start of ETOH infusion, the animals received intravenously either sterile saline or LPS (100 micrograms/100 g body weight) and were sacrificed at the end of ETOH infusion. Blood neutrophils and liver plasma membranes were isolated, and TNF-alpha binding characteristics determined using recombinant human [125I]TNF-alpha. ETOH treatment alone induced a significant decrease (51%) of neutrophil Bmax for TNF-alpha, without affecting the cytokine binding to plasma membranes. LPS, with or without ETOH, significantly decreased (61%) neutrophil Bmax for TNF-alpha and increased (115%) its binding to liver plasma membranes. The KD values of binding to either neutrophils or liver plasma membranes were not altered by ETOH or LPS treatment of animals. By decreasing the cytokine binding to neutrophils, ETOH may impair the control exerted by TNF-alpha on cell function, thus damaging host defense.
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PMID:Effect of acute alcohol administration on TNF-alpha binding to neutrophils and isolated liver plasma membranes. 132 Aug 7

Nitric oxide (NO), apart from its properties as a vasodilator, is a cytotoxic agent released from macrophages upon stimulation with immunomodulating agents such as interferon-gamma and endotoxin. In rat Kupffer cells endotoxin causes the release of NO as well as of tumor necrosis factor-alpha and prostaglandin E2 (PGE2). This eicosanoid and its second messenger, cyclic AMP, have been shown to increase nitric oxide formation in Kupffer cells treated with endotoxin (Gaillard et al. (1991) Pathobiology 59, 280-283). But not only added PGE2 but also the prostaglandin produced endogenously upon stimulation with endotoxin increases NO synthesis. Neither tumor necrosis factor-alpha nor interleukin-1 beta stimulate NO synthesis by themselves, but together with PGE2 they are as effective as lipopolysaccharide plus PGE2. To replace PGE2 in the combination with the cytokines, however, dibutyryl cAMP has to be present in higher concentrations than with LPS. Interleukin-6 alone or in combination with PGE2 or dibutyryl cAMP is without any effect. Anti-TNF-alpha as well as anti-PGE2 antibodies reduce the release of NO upon stimulation with LPS. Consequently, the effect of LPS on NO production seems to be in part due to the self-stimulating effect of PGE2 and some cytokines, both produced by Kupffer cells upon LPS stimulation.
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PMID:Regulation by prostaglandin E2 of cytokine-elicited nitric oxide synthesis in rat liver macrophages. 133 72

E. histolytica infections induce a state of transient suppression of cell-mediated immunity. As macrophages are involved in host defense in amebiasis, we determined whether soluble amebic lysates (Eh) can modulate TNF-alpha, IL-1 alpha/beta and c-fos gene expression in naive bone marrow-derived macrophages (BM delta). By Northern analysis, the RNA production of these genes after 0, 0.5, 1 and 3 h exposure to Eh was determined and compared to lipopolysaccharide (LPS) stimulation. In response to Eh, TNF-alpha mRNA was increased two fold while IL-1 alpha/beta RNA levels were increased 6- and 19-fold, respectively. Pretreatment of BM delta with H7, a PKC inhibitor, abrogated Eh induced TNF-delta gene expression and reduced IL-1 alpha/beta gene expression 3.5- to 4-fold over control levels. We conclude that E. histolytica stimulates BM delta to induce TNF-alpha gene expression through a PKC-dependent pathway and IL-1 alpha/beta gene expression partially through PKC and another yet undetermined pathway(s).
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PMID:Entamoeba histolytica modulates TNF-alpha, IL-1 alpha/beta and c-fos gene expression in macrophages. 134 Feb 79

In the present study, we have shown that the addition of culture supernatants from HIV-infected SupT1 cells (T4) but not from noninfected cells markedly increased the production of TNF-alpha by U937 promonocytic cells after stimulation with phorbol 12-myristate 13-acetate (PMA). Pretreatment of supernatants with the antibodies to granulocyte/macrophage colony-stimulating factor (GM-CSF) or TNF-alpha, but not interferon-gamma, significantly diminished this enhancing effect. These results suggest that HIV may play an indirect role by producing cytokines from infected T4 cells that can lead to an increased production of TNF-alpha by monocytic cells. Further, TNF-alpha produced by U937 cells following stimulation with PMA plus lipopolysaccharide or with phytohemagglutinin induced lysis of HIV-infected T cells. TNF-alpha-induced cytotoxicity was markedly higher toward HIV-infected than toward noninfected T4 cells. Addition of antibody to TNF-alpha during the cytotoxic phase of response resulted in a reduction of about 50% in the percentage of cytotoxicity, indicating TNF-alpha as one of the lytic mediators.
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PMID:TNF-alpha production by U937 promonocytes is enhanced by factors released from HIV-infected T4 lymphocytes: TNF-alpha is one of the mediators causing lysis of HIV-infected T4 cells. 134

Leukosialin (CD43) is a sialic acid-rich molecule with a relative molecular mass (M(r)) of 140,000 highly represented on polymorphonuclear neutrophils (PMN) and on most leukocytes. One of its functions may be to prevent nonspecific cell-to-cell interactions through negative charge repulsions. As tested by immunofluorescence, neutrophil CD43 membrane expression was shown to decrease by up to 80% upon cell activation by phorbol myristate acetate (10 ng/ml) or by N-formyl-L-methionyl-L-leucyl-L-phenylalanine (FMLP; 10(-6) M) in the presence of cytochalasin B. The kinetic of this decrease paralleled that of CD11b up-regulation. FMLP alone, tumor necrosis factor (TNF-alpha), lipopolysaccharide and granulocyte macrophage colony-stimulating factor had moderate or insignificant effects, while inducing striking CD11b up-regulation. Cell priming with TNF-alpha followed by FMLP stimulation resulted in up to 40% decrease of CD43 expression. Anti-CD43 mAb immunoprecipitated three fragments of M(r) 130,000, 49,000 and 34,000 from the cell-free supernatant of activated neutrophils, suggesting that CD43 is released from the membrane by proteolysis. Indeed, the decrease in CD43 expression was inhibited by phenylmethanesulfonylfluoride (PMSF). Homotypic aggregation of activated PMN was also inhibited by PMSF and could result, at least in part, from the shedding of CD43. The shedding of such a strongly anionic and major membrane protein should drastically modify PMN surface charge and may allow previously hindered interactions by exposing new adhesion molecules.
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PMID:Human neutrophils release their major membrane sialoprotein, leukosialin (CD43), during cell activation. 135 26


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