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)

To clarify which cytokines could potentially be produced by astrocytes, we have assessed the presence of mRNA for a number of cytokines in astrocyte-enriched brain cultures. The cultures were derived from neonatal murine brain and were treated with either interferon-gamma, lipopolysaccharide or tumor necrosis factor-alpha, or infected with murine cytomegalovirus. RNA was extracted at 0, 4, 24 and 48 hours post treatment. A DNA copy of total cytoplasmic RNA was synthesised and specific cDNA amplified using the polymerase chain reaction and detected by hybridization with specific probes. The following cytokines were studied: IL3, IL4, IL6, TNF alpha, TGF beta, LIF, G-CSF, M-CSF and GM-CSF. Transcripts for TGF beta, IL6, LIF and M-CSF were present constitutively but increased with stimulation, whereas transcripts for TNF alpha, IL6, GM-CSF, G-CSF and LIF were detected only after stimulation. Messenger RNA for IL3 and IL4 was not detected. The magnitude and kinetics of the induction varied according to the cytokine and the stimulus. These results indicate the possibility of intra-cerebral production of a number of cytokines that may play a role in the clearance of viral or bacterial pathogens and in the generation of neuropathology.
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PMID:Detection of cytokine mRNA in astrocyte cultures using the polymerase chain reaction. 216 30

1. Induction of tumor cell differentiation could reverse transformed cells into normal, mature cells. Important question is whether these malignant-to-normal reversed cells are really normal ones. 2. We have developed an experimental model based on the examination of three different levels of human acute myeloid leukemia cell properties before and after induction of differentiation: morphological (percentage of undifferentiated blast cells), functional (DNA ploidy, Fc receptors, phagocytic activity, clonogenic assay in soft agar, oxidative metabolism which accompanies phagocytosis in mature granulocytes) and genetical (expression of oncogene p53). 3. Several inducers have been employed: dimethylsulfoxide (DMSO) granulocyte-macrophage colony stimulating factor (GM-CSF); tunicamycin, interferon gamma, tumor necrosis factor and lipopolysaccharide. 4. Our results indicate that the reversion of leukemic cells into mature normal ones with some inducers (DMSO, GM-CSF) could be a complete process.
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PMID:Artificial reversion of acute myeloid leukemia cells into normal phenotype. 218 58

We have previously reported that lipopolysaccharide (LPS) could induce the production of interleukin-3 (IL-3) by mouse spleen cells. In the present study, we show that recombinant human interleukin-1, in the absence of other stimuli, is able to induce the production of IL-3. IL-3 was detected in the supernatants of adult, although neither in young nor in nude mouse splenocytes and was assessed by its capacity to support the growth of the IL-3-dependent FDC-P2 cell line. The presence of IL-3 was antigenically confirmed with a monoclonal anti-IL-3 antibody. Both recombinant IL-1 alpha and IL-1 beta had similar potential for inducing IL-3 production. IL-3 activity was detected in the supernatants of cells cultured in the presence of 100 pg/ml IL-1; maximal IL-3 levels were obtained with 10-30 ng/ml IL-1. Kinetic studies of IL-1-induced IL-3 production indicated that 4-6 days of culture were required for optimal production, whereas 1-2 days were sufficient in cultures stimulated with concanavalin A. Recombinant IL-6 failed to induce significant amounts of IL-3, and TNF alpha induced only weak IL-3 production. GM-CSF but not M-CSF could lead to the appearance of IL-3 in spleen cell culture supernatants. Removal of macrophages decreased the production of IL-3 induced by LPS and GMF-CSF though did not affect the IL-3 production induced by IL-1. This observation suggests that IL-1 production might be an intermediate event in IL-3 production induced by LPS and GM-CSF through the activation of macrophages. IL-3 was detected in culture supernatants of B-cell-depleted splenocytes indicating that T-cells were the source of IL-3. Surprisingly T-cell-depleted populations could also produce IL-3 upon IL-1 stimulation. Preliminary experiments with an autoreactive CD4- CD8- V beta 8+ clone suggested that these cells might also be involved in the described IL-3 production.
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PMID:Induction of interleukin-3 by interleukin-1 in the absence of other exogenous stimuli. 236 39

The macrophage and granulocyte colony-stimulating factors, M-CSF and G-CSF, act in vitro to induce proliferation and differentiation of monocyte and granulocyte progenitor cells, respectively. We show here that both of these CSFs can be produced by stimulated human blood monocytes, but the M-CSF and G-CSF genes are independently regulated. Recombinant human interleukin-3 (IL-3) and GM-CSF primarily induce expression of the M-CSF gene and secretion of M-CSF, whereas bacterial lipopolysaccharide primarily induces expression of the G-CSF gene and secretion of G-CSF. These results suggest that under different conditions of in vitro stimulation the monocyte secretes factors that could lead selectively to either granulocyte or monocyte production.
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PMID:Independent regulation of M-CSF and G-CSF gene expression in human monocytes. 245 27

A fibroblast proliferation assay was developed for the detection of interleukin 1 (IL 1). Proliferation was measured by thymidine incorporation and by staining of cellular proteins with crystal violet. Response of fibroblasts was optimal at cell numbers of 4,000 to 9,000 cells/culture and an incubation period of four days. Serum content of the culture medium, ranging from 1 to 10% fetal calf serum (FCS), enhanced the proliferative response in a concentration-dependent manner, while higher concentrations of FCS did not lead to further increase. Both detection methods were equally suitable for the measurement of IL 1 biological activity in purified and crude preparations. In contrast to the conventional thymocyte comitogenic assay, the fibroblasts in this assay did not proliferate in response to IL 2 or IL 6. Fibroblasts were weakly stimulated by recombinant (rec) tumor necrosis factor (rec TNF-alpha); they did, however, not proliferate in response to mitogens, lipopolysaccharide, rec granulocyte-macrophage colony stimulating factor (rec GM-CSF), macrophage-CSF, rec interferon-gamma, insulin or transferrin. The detection of IL 1 activity by crystal violet staining of human dermal fibroblasts was easier and faster than by measurement of thymidine incorporation of fibroblasts or mouse thymocytes; without loss of sensitivity, the sample capacity of the IL 1 assay could be enhanced, and the use of experimental animals was avoided.
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PMID:Detection of interleukin 1 with human dermal fibroblasts. 247 29

Peritoneal macrophages elicited by Lactobacillus casei YIT9018 (LCEPM) were incubated in culture for 18 h with L. casei; the culture supernatant (LCM) was then harvested and tested for its ability to increase the cytostatic activity of resident peritoneal macrophages (RPM) and LCEPM. Treatment of RPM with LCM induced activation of macrophages to a cytostatic state against L929, Colon 26, P815, P388D1 and L1210 cells. A combination of recombinant human tumor necrosis factor (rhTNF), recombinant mouse TNF (rmTNF), recombinant human interleukin-1 (rhIL-1) or bacterial lipopolysaccharide with recombinant mouse interferon gamma (rmIFN-gamma) resulted in the synergistic induction of cytostatic activity in RPM. Recombinant mouse granulocyte-macrophage colony-stimulating factor (rmGM-CSF) plus rhTNF increased the cytostatic activity of RPM a little but rmGM-CSF or rhTNF combined with rhIL-1 or alone had no effect. The effect of LCM on RPM was not inhibited by polymyxin B, anti-mTNF antiserum or below 20 U/ml monoclonal anti-rmIFN-gamma antibody (anti-rmIFN-gamma) but was inhibited by more than 40 U/ml anti-rmIFN-gamma, and LCM did not have any interferon antiviral activity. These results suggest that the cytostatic activity of RPM was augmented by the LCM, and that the effect of the LCM may be not due to IFN-gamma, TNF, GM-CSF, IL-1 or a small amount of contaminating lipopolysaccharide.
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PMID:Role of culture supernatant of cytotoxic/cytostatic macrophages in activation of murine resident peritoneal macrophages. 249 78

Interleukin-1 (IL-1), a cytokine, primarily produced by monocytes, is the molecule involved in mediating many of the body's responses associated with infection and inflammation. More recently, IL-1 has been shown to sustain elevated levels of circulating granulocytes, stimulate the production of granulocyte-macrophage colony stimulating factors (CSFs) in vitro, increase plasma levels of CSF, and act synergistically with CSFs to increase the number of granulocyte-macrophage progenitors (colony-forming units) (CFU-GM) in vitro. The purpose of this study was to investigate the effect of murine IL-1 on steady-state hematopoiesis in vivo. C3H/HeJ or its normal littermate C3H/HeN male mice were administered either murine recombinant IL-1 at 45, 50, 200, 225, or 900 units (0.0125-0.25 micrograms)/animal, or 200 units (0.05 micrograms) of semipurified IL-1 derived from P388D1 cell culture supernatants. Because one of the responses to IL-1 is increased prostaglandin (PG) production and with the known activity of PGs on hematopoiesis, additional studies incorporated the cyclooxygenase inhibitor indomethacin (IM) (10 mg/kg body weight). In order to study the effect of IL-1 in vivo on pluripotential progenitors (CFU-S), IL-1 was compared with recombinant murine GM-CSF (50, 200, and 900 units; 0.0125, 0.05, and 0.25 micrograms). Control groups consisted of animals receiving either lipopolysaccharide (0.5 mg/kg body weight) or phosphate-buffered saline where appropriate. After 24 h, animals were sacrificed, and their peripheral blood indices and stem cell content of both bone marrow and spleen were evaluated for various committed hematopoietic progenitors: CFU-GM, CFU-Meg, CFU-E, BFU-E, and CFU-DG. Circulating neutrophils were increased following IL-1; however, this increase was reduced following IM. IL-1 marrow-derived CFU-GM, CFU-E, BFU-E, and CFU-Meg were below controls. In contrast, splenic CFU-GM and CFU-Meg were significantly elevated with increasing IL-1 concentrations. Erythroid progenitors were increased following low IL-1 concentrations and reduced in animals receiving IM, thus indicating a role for prostaglandins in the mechanism of IL-1 for influencing hematopoiesis. CFU-DG were increased, however, only when animals were pretreated with IL-1 and their cells implanted into normal hosts, not when normal cells were implanted into animals pretreated with IL-1, indicating a potential target cell effect rather than an indirect, factor-related response.(ABSTRACT TRUNCATED AT 400 WORDS)
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PMID:Modulation of murine hematopoiesis in vivo with recombinant murine interleukin-1. 266 87

Different clones of myeloid leukemic cells can be induced to differentiate to mature macrophages and/or granulocytes by hematopoietic regulatory proteins and by other compounds. We now show that induction of differentiation in different clones of myeloid leukemic cells with the normal hematopoietic proteins granulocyte-colony stimulating factor (G-CSF), granulocyte-macrophage colony stimulating factor (GM-CSF), or interleukin 3 and by compounds such as dexamethasone or cytosine arabinoside (ara C) induces the expression of genes for the myeloid differentiation inducing protein MGI-2 that we have shown is interleukin 6 (IL-6) and for GM-CSF. We have previously shown that induction of differentiation with interleukin-1, IL-6, or bacterial lipopolysaccharide (LPS) also induces IL-6 and GM-CSF gene expression. Treatment of these leukemic clones with hematopoietic proteins that do not induce differentiation did not induce IL-6 or GM-CSF gene expression. The results indicate that induction of IL-6 and GM-CSF gene expression is part of the normal differentiation program in myeloid cells and support our previous evidence that there is transregulation of gene expression between different hematopoietic regulatory proteins.
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PMID:Regulation of the genes for interleukin-6 and granulocyte-macrophage colony stimulating factor by different inducers of differentiation in myeloid leukemic cells. 268 77

We investigated normal human mesothelial cells and human malignant mesothelioma cell lines for the ability to produce hematopoietic colony-stimulating factors (CSFs) in culture. Early passage cultures of normal diploid human mesothelial cells spontaneously expressed detectable levels of M-CSF mRNA transcripts, but lacked detectable transcripts for GM-CSF or G-CSF. Exposure of normal mesothelial cells to epidermal growth factor (EGF), lipopolysaccharide (LPS), or tumor necrosis factor (TNF) induced expression of G-CSF mRNA. The combination of EGF and TNF induced threefold more G-CSF transcripts than did either factor alone. GM-CSF transcripts were induced only by the combination of TNF and EGF. Interleukin-1 beta (IL-1 beta) transcripts were induced by EGF, TNF, or LPS and were inhibited by hydrocortisone (HC). All malignant mesothelioma cell lines tested also spontaneously expressed M-CSF transcripts. However, in contrast to normal mesothelial cells, two of four malignant mesothelioma cell lines also autonomously expressed G-CSF and GM-CSF transcripts without TNF, EGF, or LPS stimulation. Secretion of biologically active CSFs was confirmed by testing media conditioned by the various cell types examined. The detection of biologically active CSFs correlated well with the presence of detectable CSF transcripts by Northern analysis. These data indicate that (a) normal human mesothelial cells spontaneously express detectable levels of M-CSF mRNA in culture; (b) EGF is an essential cofactor for optimal induction of G-CSF and GM-CSF expression; (c) exposure of normal mesothelial cells to inflammatory mediators such as LPS and TNF increases the levels of transcripts for CSFs and IL-1 beta; and (d) as compared with normal human mesothelial cells, some cell lines of human malignant mesothelioma exhibit aberrant gene expression for multiple cytokines, including G-CSF, GM-CSF, IL-1 beta, and IL-6.
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PMID:Expression of colony-stimulating factor genes by normal human mesothelial cells and human malignant mesothelioma cells lines in vitro. 278 82

In contrast to mature spleen cells and macrophages, which produce colony-stimulating factor (CSF) in response to lipopolysaccharide (LPS), murine bone marrow (BM) cells do not respond to LPS alone. However, when BM cells are treated with LPS and the tumor-promoting phorbol ester 12-O-tetradecanoyl-phorbol-13-acetate (TPA) simultaneously, they generate significant levels of CSF. The non-tumor-promoter 4-O-methyl-TPA will not replace TPA, and if BM cells from C3H/HeJ mice are employed, no CSF is produced after stimulation with LPS and TPA. Lipid A is as effective as LPS in stimulating BM cells in the presence of TPA, but other mitogens, such as phytohemagglutinin (PHA), concanavalin A (Con A), or pokeweed mitogen (PWM), are ineffective. B-lymphocytes may be the main source of the CSF from BM cells, since BM cells adherent to surfaces coated with goat antimouse immunoglobulin produced CSF in amounts similar to those produced by unseparated BM cells after stimulation with LPS and TPA. Finally, the CSFs produced by BM cells under these experimental conditions were identified as belonging to the GM-CSF and G-CSF subclasses. We interpret these results as suggesting that B cells present in the BM, as opposed to mature spleen cells and macrophages, require at least two signals for CSF production.
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PMID:Synergistic action of lipopolysaccharide and tumor-promoting phorbol esters: two-signal requirement for colony-stimulating factor production by murine bone marrow cells. 294 98


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