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)

Bone marrow stromal cells produce cytokines that are essential for the proliferation and differentiation of hematopoietic stem and progenitor cells. Thus, regulation of cytokine production by bone marrow accessory cells is a critical aspect of stromal cell regulation of hematopoiesis. We have investigated the effect of two cytokines that have been demonstrated to modulate factor production by non-marrow accessory cells (i.e., transforming growth factor-beta 1 [TGF-beta 1] and interleukin-4 [IL-4]) on the induced expression of cytokine mRNA in a bone marrow-derived, cloned, murine stromal cell line +/+/-.LDA11. We showed that +/+/-.LDA11 cells can be induced with lipopolysaccharide (LPS), IL-1 alpha, or interferon-gamma (IFN-gamma) to express mRNA for monocyte chemoattractant protein-1 (MCP-1/JE), IFN-inducible protein-10 (IP-10), stem cell factor (SCF), and macrophage colony-stimulating factor (M-CSF) but not for IL-1 alpha, IL-3, or tumor necrosis factor-alpha (TNF-alpha). The expression of MCP-1/JE and IP-10 mRNA by these inducers was potentiated by TGF-beta 1 and IL-4. The augmentation by TGF-beta 1 of both mRNAs induced with IL-1 alpha was maximum when applied to the cells concurrently with the inducer; the IFN-gamma-induced expression of mRNAs was augmented even if the addition of TGF-beta 1 was delayed. Similarly, IL-4 potentiation of both mRNAs by either inducer progressively increased as the time between exposure to the inducer and exposure to IL-4 increased. Neither modulator altered the time course of mRNA expression by either inducer. TGF-beta 1- and IL-4-mediated augmentation of MCP-1/JE mRNA by IL-1 alpha or IFN-gamma was partially reversed by cycloheximide (CHX), whereas potentiation of IP-10 by either modulator remained unaffected. Increase in the stability of mRNA transcripts by TGF-beta 1 or IL-4 does not appear to play a role in the enhanced accumulation of mRNA in the presence of the modulators. These findings support a role for TGF-beta 1 and IL-4 as critical regulatory molecules in production of MCP-1 and IP-10 chemokines by stromal cells.
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PMID:Induction of chemokine mRNA in bone marrow stromal cells: modulation by TGF-beta 1 and IL-4. 776 3

A critical step in development of atherosclerosis is the interaction of oxidized low-density lipoprotein (LDL) with mononuclear phagocytes. Oxidized LDL, as well as acetyl-LDL, is rapidly taken up into macrophages via a family of scavenger receptors. We report that macrophages treated with oxidized LDL have markedly lower levels of mRNA specific for the genes MCP-1, TNF-alpha, IL-1 alpha, and KC as measured by Northern blot analyses of lipopolysaccharide (LPS)-stimulated macrophages. By contrast, acetyl-LDL does not inhibit these genes at the doses at which oxidized-LDL is effective. Similar effects are observed whether the LDL is oxidized in the presence of Cu2+ or of Fe2+. Such inhibition also occurs when maleylated bovine serum albumin (BSA), which also clears by one or more scavenger receptors on macrophages, is used as the stimulant. Fe2+ or Cu2+ oxidized LDL inhibits release of nitric oxide when triggered by LPS and direct cytolysis of tumor cells when triggered by maleylated BSA or LPS. Taken together, the data presented indicate that oxidized LDL inhibits induction of several important gene RNAs as well as functional markers that characterize the development of inflammatory and fully activated macrophages.
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PMID:Effects of oxidized LDL on mononuclear phagocytes: inhibition of induction of four inflammatory cytokine gene RNAs, release of NO, and cytolysis of tumor cells. 788 14

The purpose of this study was to determine whether the expression of the JE/MCP-1 gene encoding for the monocyte chemottractant protein, MCP-1 (also known as monocyte chemotactic and activating factor MCAF, TDCF, and SMC-CF) can influence the metastatic properties of tumor cells. The highly metastatic murine colon carcinoma CT-26 cells, syngeneic to BALB/c mice that do not produce endogenous JE/MCP-1 protein, were transfected with a BCMGS-Neo expression vector (control) or a vector containing full-length JE cDNA. CT-26 parental cells, CT-26 Neo, and CT-26 JE/MCP-1-positive cells were injected into syngeneic or nude mice. The CT-26 JE/MCP-1-positive cells produced significantly fewer lung metastases. The decrease in incidence of metastasis was not due to the inability of the transfected cells to arrest in the lung vasculature or to differences in cell cycle time. CT-26 cells producing JE/MCP-1 were highly susceptible to lysis by syngeneic macrophages treated with subthreshold concentrations of lipopolysaccharide. In addition, culture supernatants of JE/MCP-1-expressing cells plus lipopolysaccharide synergistically activated tumoricidal properties in syngeneic macrophages. This activity was blocked by anti-JE/MCP-1 antibodies, indicating the involvement of the JE/MCP-1 molecule in this process. Moreover, purified JE/MCP-1 added to lipopolysaccharide-containing medium resulted in significant activation of macrophages against parental CT-26 cells. These data suggest that, in addition to its chemotactic properties, JE/MCP-1 can synergize with bacterial endotoxins to activate macrophages to become tumoricidal and, hence, could suppress metastasis.
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PMID:Expression of the JE/MCP-1 gene suppresses metastatic potential in murine colon carcinoma cells. 795 25

C/EBP-related proteins 2 and 3 (CRP2 and CRP3) are differentially expressed by P388 lymphoblasts and their derivative P388D1(IL1) macrophages. We have ectopically expressed CRP2, the predominant CRP in macrophages, in P388 lymphoblasts. The expression of CRP2 is sufficient to confer the lipopolysaccharide (LPS)-inducible expression of interleukin 6 and monocyte chemoattractant protein 1 to lymphoblasts, which normally do not display LPS induction of inflammatory cytokines. Consistent with these findings, the expression of CRP2 antisense RNA blocks the LPS induction of IL-6 expression in P388D1(IL1) macrophages. This work clearly establishes the essential role of CRP2 in the induction of cytokine genes by LPS. Additionally, these data add MCP-1 to the list of cytokines showing an involvement of CRP2 in their expression.
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PMID:C/EBP-related protein 2 confers lipopolysaccharide-inducible expression of interleukin 6 and monocyte chemoattractant protein 1 to a lymphoblastic cell line. 804 85

Constitutive expression of mRNAs for GRO alpha, GRO beta, GRO gamma, and MCP-1, belonging to the chemokine family of 8- to 10-kDa cytokines with chemotactic properties for granulocytes and monocytes, has been identified in freshly isolated human nasal and bronchial epithelium, and in bronchoalveolar macrophages (AM). Expression of GRO alpha, GRO gamma, and MCP-1, but not GRO beta, was found in airway epithelial cells. AM expressed all three GRO genes in addition to MCP-1. On reverse transcription, chemokine mRNAs yielded 0.5-30 cDNA molecules/cell, depending on the chemokine and cell type, as determined by a semiquantitative reverse transcriptase-polymerase chain reaction technique. When chemokine mRNA expression in AM and bronchial epithelium from healthy nonatopic individuals was compared, AM expressed more GRO alpha, but similar levels of GRO gamma, MCP-1, and interleukin-8 (IL-8), as in the bronchial epithelial cells. Modulation of chemokine expression by tumor necrosis factor-alpha (TNF-alpha; 10 ng/ml) or endotoxin [lipopolysaccharide (LPS), 100 ng/ml] exposure was studied in primary nasal epithelial cell and alveolar macrophage cultures. In epithelial cells, LPS did not induce chemokine expression but GRO alpha, IL-8, and MCP-1 were upregulated approximately 100-fold by TNF alpha; GRO gamma expression was elevated only 1.5- to 4-fold. In AM cultures, all three GROs were strongly induced by LPS with peak mRNA expression 24 h after stimulation (approximately 50- to 100-fold increase compared with control cultures). MCP-1 mRNA expression, on the other hand, was not increased by LPS in AM. GRO protein was present in supernatants of stimulated epithelial cells and AM.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Constitutive and stimulated MCP-1, GRO alpha, beta, and gamma expression in human airway epithelium and bronchoalveolar macrophages. 816 97

We examined the relation between glomerular expression of chemokines from alpha-subfamily (macrophage inflammatory protein-2, MIP-2) and beta-subfamily (monocyte chemoattractant protein-1, MCP-1) and infiltration of neutrophils and monocytes in antibody mediated glomerulonephritis in rats. In the accelerated model of nephrotoxic nephritis (NTN), glomerular expression of MIP-2 and MCP-1 genes correlated with the sequential migration of neutrophil and monocyte influx, respectively. These relationships were investigated further in the heterologous phase of NTN by applying various treatments known to modulate the severity of injury. Pretreatment with bacterial lipopolysaccharide resulted in greater injury, MIP-2 expression increased 25- to 50-fold, and the glomerular neutrophil count increased two- to fourfold. Both MIP-2 mRNA levels and neutrophil infiltration were reduced by additional pretreatment with IL-6, IL-1 receptor antagonist, soluble IL-1 receptor or soluble TNF receptor (Spearman correlation coefficient r = 0.897, P < 0.005). In the heterologous phase of NTN, different pre-treatments only resulted in trivial changes in MCP-1 expression and monocyte infiltration. In conclusion, glomerular MIP-2 gene expression correlates with neutrophil infiltration both temporally during the evolution of nephritis, and when glomerular injury is modified by treatment. Glomerular MCP-1 gene expression correlates with monocyte influx. The data show chemokines of alpha- and beta-subfamilies co-operative to cause selective and sequential migration of different leukocyte subsets during development of antibody mediated glomerulonephritis.
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PMID:Differential expression of macrophage inflammatory protein-2 and monocyte chemoattractant protein-1 in experimental glomerulonephritis. 864 12

Leukocyte infiltration into an inflammatory site is one of the pathological hallmarks of inflammatory reaction. Locally produced chemotactic factors are presumed to mediate the sequence of events leading to tissue injury associated with the infiltration of leukocytes. Chemotactic cytokines (chemokines) have been identified as being produced by various types of cells upon stimulation with inflammatory stimuli and exhibit a variety of effects on leukocytes in vitro and in vivo. Administration of highly specific neutralizing antibodies against these chemokines in several types of animal inflammation models clearly suggests important roles of these chemokines in recruiting and activating specific types of leukocytes at the inflammatory sites. Anti-IL-8 Ab treatment prevented neutrophil-dependent tissue damage as well as neutrophil infiltration in lipopolysaccharide (LPS)-induced dermatitis, LPS/IL-1-induced arthritis, lung reperfusion injury, and acute immune complex type glomerulonephritis in rabbits. Moreover, anti-MCP-1 Ab and anti-RANTES Ab inhibited macrophage infiltration in IgA immune complex alveolitis in rats and influx of lung macrophages in a murine model of endotoxemia, respectively. The use of anti-MIP-1alpha Ab also revealed that MIP-1alpha mediates eosinophil infiltration in allergic, granulomatous reactions in vivo.
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PMID:Use of Blocking Antibodies as Probes for in Vivo Functions of Chemokines 881 62

Following the intracranial injection of lipopolysaccharide or during acute neuronal degeneration, there is a paucity of polymorphonuclear leukocyte recruitment to the brain parenchyma and a delay in monocyte recruitment. The present study investigates whether the injection of specific leukocyte chemoattractants into the murine central nervous system can override this intrinsic resistance. Recombinant alpha-(IL-8/NAP-1 MIP-2, IP-10) and beta-chemokines (MCP-1, RANTES) were injected into the murine hippocampus and leukocyte recruitment was assessed histologically. Injections were also made into the dermis of the hind flank for comparison. At doses of 1 microgram, MCP-1 was found to be the most potent monocyte chemoattractant in the brain parenchyma and skin with IP-10 and RANTES producing minimal monocyte recruitment to both sites. In contrast IL-8, and MIP-2 provoked dramatic polymorphonuclear leukocyte recruitment in both the central nervous system and skin. The polymorphonuclear leukocyte recruitment was associated with a breaching of the blood brain barrier that was particularly severe after MIP-2. Both L-8 and MIP-2 induced blood brain barrier breakdown could be attenuated by prior depletion of the circulating leukocytes. The regulation of polymorphonuclear leukocyte chemoattractants in the brain parenchyma during injury and infection is an important area for future studies.
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PMID:Overriding the brain's intrinsic resistance to leukocyte recruitment with intraparenchymal injections of recombinant chemokines. 884 93

In the present study, we show that cultured rat brain macrophages release a soluble factor that stimulates the migration of bone marrow-derived macrophages, as determined by an in vitro chemotaxis assay. A checkerboard analysis indicated that most of this effect resulted from a polarized migration of the cells (chemotactic phenomenon), rather than in an increase in cell motility (chemokinesis). This activity was significantly decreased by an immune serum directed against the rat monocyte chemoattractant protein-1 (chemokine MCP-1). Northern blot analysis demonstrated expression of the MCP-1 gene in cultured brain macrophages, but its absence in unstimulated bone marrow-derived macrophages. Up-regulation of MCP-1 expression was observed when lipopolysaccharide was added to cultured brain macrophages, a peak occurring after a 6 h period of stimulation. Also, inflammatory cytokines such as interleukin (IL)-1 beta, colony stimulating factor-1, tumour necrosis factor-alpha and IL-6 individually increased the basal level of MCP-1 mRNA. Subsequently, we demonstrated the in vivo production of MCP-1 in the adult rat brain following injury induced by a local injection of kainic acid. MCP-1 synthesis was localized in both astrocytes and brain macrophages. These results suggest that the activation of resting microglial cells into brain macrophages and their subsequent secretion of chemokines could contribute to the mechanism(s), leading to the infiltration of the CNS by blood-derived monocytes, as observed in several pathologies.
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PMID:Production of monocyte chemotactic protein-1 by rat brain macrophages. 892 Dec 63

PTX3 is a prototypic long pentraxin composed of a C-terminal domain similar to those of classical pentraxins (e.g., C reactive protein) and an unrelated N-terminal portion. PTX3 is expressed in a variety of cell types, notably mononuclear phagocytes and endothelial cells, after exposure to the inflammatory cytokines interleukin-1beta (IL-1beta) and tumor necrosis factor alpha (TNF-alpha). The present study was designed to assess whether mycobacterial components were able to induce expression and production of PTX3. Mycobacterial lipoarabinomannan (LAM) induced expression of PTX3 mRNA in human peripheral blood mononuclear cells. The non-mannose-capped version of lipoarabinomannan (AraLAM) was considerably more potent than the mannose-capped version ManLAM or the simpler version phosphatidylinositol mannoside. Among mononuclear cells, monocytes were responsible for LAM-induced PTX3 mRNA expression. Whole mycobacteria (Mycobacterium bovis BCG) strongly induced PTX3 expression. Pretreatment with actinomycin D abolished LAM-induced PTX3 expression, whereas cycloheximide only partially reduced the expression. LAM-induced PTX3 expression was associated with the production of immunoreactive PTX3. IL-10 and IL-13 did not inhibit the induction of PTX3 by LAM. Under the same conditions, these anti-inflammatory cytokines inhibited MCP-1 expression. In contrast, gamma interferon inhibited LAM-induced PTX3 expression. Thus, in addition to IL-1, TNF, and lipopolysaccharide, mycobacterial cell wall components also induce expression and production of the long pentraxin PTX3. The significance of PTX3 in the immunobiology of mycobacterial infection and its relevance in relation to clinical involvement remain to be determined.
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PMID:Expression of a long pentraxin, PTX3, by monocytes exposed to the mycobacterial cell wall component lipoarabinomannan. 911 72


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