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 examine the immunopharmacological actions of an extract isolated from inflamed skin of rabbits inoculated with Vaccinia virus (Neurotropin), its effect on the immune responses in aging BALB/c mice was examined. Neurotropin clearly restored the decreasing T-cell-dependent immune responses such as delayed-type hypersensitivity (DTH) response and plaque-forming cells (PFC) response to sheep red blood cells (SRBC) when administered i.p. from 13 months old (mo) to 16 mo. However, Neurotropin administration from 2 to 5 mo had no effect on the immune responses of young animals. Neurotropin administration from 13 to 16 mo restored not only the T-cell proliferation of spleen cells induced by concanavalin A (Con A) and phytohemagglutinin (PHA), but also the interleukin-2 (IL-2) production by spleen cells activated with Con A. However, Neurotropin did not affect the responsiveness of Con A-activated spleen cells to exogenous recombinant IL-2. An absence of suppressor cells capable of inhibiting the IL-2 production in the spleens was confirmed in the 16 mo mice. Neurotropin administration also restored IL-1 production by peritoneal macrophages stimulated with lipopolysaccharide (LPS). These results suggest that long-term administration of Neurotropin restores the decreasing T-cell-dependent immune responses through the recovery of IL-2 and in part IL-1 production, but not the responsiveness to IL-2 in aging BALB/c mice.
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PMID:Immunopharmacological actions of an extract isolated from inflamed skin of rabbits inoculated with Vaccinia virus (Neurotropin)--II. Restorative effect on immune responses through the recovery of IL-2 production in aging mice. 268 Oct 5

Osteoblasts play a central role in the regulation of bone remodeling. Not only are they responsible for the formation of new bone, but they also regulate bone resorption. These cells also exert regulatory influences outside the bone in that they are able to regulate hematopoiesis. However, obtaining pure populations of osteoblasts devoid of contaminating cell types remains problematic. One approach to this problem is the use of cloned osteoblastic cell lines. To this end we have used MC3T3-E1, a cloned murine osteoblast cell line of C57BL/6 origin. We report that MC3T3-E1 cells respond to lipopolysaccharide (LPS) and, to a lesser extent, parathyroid hormone (PTH) by the secretion of granulocyte-macrophage colony-stimulating factor (GM-CSF). However, 1,25-(OH)2D3, a potent activator of osteoblasts, fails to induce these cells to secrete GM-CSF. These results suggest that MC3T3-E1 cells respond to osteotropic agents in a hierarchical fashion. Secretion of GM-CSF is not constitutive but rather requires active induction of the cells. MC3T3 cells fail to secrete detectable levels of interleukin-2 (IL-2), IL-3, or IL-4, regardless of whether or not the cells are activated. The data indicate that MC3T3-E1 cells secrete cytokines in response to osteotropic agents in a way similar to that of normal primary osteoblasts. Therefore, MC3T3-E1 cells may serve as a good in vitro model for primary osteoblasts.
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PMID:Osteotropic agents induce the differential secretion of granulocyte-macrophage colony-stimulating factor by the osteoblast cell line MC3T3-E1. 269 6

Recent investigations have demonstrated interleukin-2 receptor (IL-2R) expression on both human alveolar macrophages (AM phi) and blood monocytes (PBM), but the function of these receptors has not been fully elucidated. In this study, we demonstrate that human AM phi, as well as PBM, can be induced to express biologically active TNF-alpha after challenge with interleukin-2 (IL-2). Furthermore, we examined the expression of TNF-alpha at the mRNA level via Northern blot and in situ hybridization analysis. Normal AM phi, obtained by bronchoalveolar lavage, and PBM were stimulated with either IL-2 (2,000 U/ml) or lipopolysaccharide (LPS) (10 micrograms/ml) for 18 h. Specificity was demonstrated by neutralizing TNF-alpha activity with a polyclonal rabbit anti-human TNF-alpha antibody. PBM TNF-alpha biologic activity from 11 subjects challenged with either IL-2 or LPS was 19 +/- 6 and 85 +/- 15 U/ml/10(6) cells, respectively, which represented 5-fold and 21-fold increases over control values. AM phi TNF-alpha biologic activity from nine subjects was 110 +/- 28 (IL-2-mediated) and 304 +/- 69 (LPS-mediated) U/ml/10(6) cells, which represented 2- and 6-fold increases over controls. AM phi exhibited statistically greater (p less than 0.05) TNF production in response to both IL-2 and LPS as compared to PBM. IL-2 challenge resulted in an induction of TNF-alpha mRNA accumulation, as demonstrated by Northern blot and in situ hybridization analyses. TNF-alpha mRNA was quantitated by laser densitometry for Northern blots or by counting the number of silver grains/mononuclear phagocytic cell in the in situ hybridization analysis.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Interleukin-2-induced tumor necrosis factor-alpha (TNF-alpha) gene expression in human alveolar macrophages and blood monocytes. 278 42

Four anticancer agents, neothramycin, aclacinomycin, FK-565 and FK-156, were tested for their effects on concanavalin-A-induced interleukin-2 release from rat splenocytes in vitro. Neothramycin showed an enhancement of the release of interleukin-2, whereas aclacinomycin had no effect. FK-565 and FK-156 were found to inhibit the release of interleukin-2 under similar conditions. The inhibition was much more marked with FK-565. These drugs were also tested for their effects on the release of interleukin-1 from rat peritoneal exudate cells stimulated by lipopolysaccharide in vitro. Neothramycin and aclacinomycin did not affect the release of interleukin-1; however, both FK-565 and FK-156 resulted in its enhanced release under these conditions.
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PMID:Effect of anticancer agents neothramycin, aclacinomycin, FK-565 and FK-156 on the release of interleukin-2 and interleukin-1 in vitro. 278 91

The effects of 14-day treatment with low doses of O,S,S-trimethyl phosphorodithioate (OSS-TMP), an impurity in technical malathion, on the generation of cell-mediated and humoral immune responses were examined in female C57BL/6 mice. At a dose of 2.0 mg/kg per day OSS-TMP, the generation of antibody-secreting cells to sheep red blood cells, the generation of cytotoxic T lymphocytes (CTL) to alloantigen and the production of Interleukin-2 were elevated approximately 2-3 fold, while no changes were observed in the proliferative responses to the polyclonal activators, Concanavalin A, lipopolysaccharide, or phytohemagglutinin. In contrast, at 5.0 mg/kg per day OSS-TMP, both the CTL and specific antibody responses were suppressed, while all other immune parameters examined were unchanged. Data from cell separation and reconstitution experiments indicated that both T and B lymphocytes were affected by these treatment regimes. These data suggest that long-term exposure to low doses of OSS-TMP may enhance the ability of an animal to generate an immune response while higher doses of OSS-TMP may suppress the generation of an immune response.
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PMID:Effects of subacute administration of O,S,S-trimethyl phosphorodithioate on cellular and humoral immune response systems. 278 38

Toluene is a known contaminant found in trace amounts in groundwater. Male CD-1 mice were exposed to 0, 17, 80, and 405 mg/liter toluene in drinking water for 4 weeks. Immune function assays were selected to evaluate specific humoral and cell-mediated immunity, interleukin-2 (IL-2) activity, hematology, along with general toxicity. Toluene produced an increase in liver weight and decrease in thymus mass at the highest dose. No effects on body weights and hematological parameters, including erythrocytes, leukocytes, and their differentials were noticed. Mitogenesis by lipopolysaccharide, pokeweed mitogen, concanavalin A, and phytohemagglutinin were suppressed in splenocytes from treated mice. Splenocyte lymphoproliferation to alloantigens decreased at the 405 mg/liter concentration only. Numbers of sheep red blood cell (SRBC)-specific plaque-forming cells decreased in the highest dosed animals; however, no significant change was observed in the serum alpha-SRBC antibody level. Toluene also adversely affected IL-2 synthesis at the 405 mg/liter concentration. Findings suggest that alteration of immune functions of mice ingesting toluene was generally evident at relatively high doses, except for splenic lymphocyte responses to selected mitogens.
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PMID:Immunotoxicological evaluation of toluene exposure via drinking water in mice. 278 14

On the basis of their recent studies, several researchers have suggested that the infertility associated with mild endometriosis is due to the alteration of peritoneal fluid, resulting in impairment of the viability of gametes or embryos. Elevated numbers of macrophages and lymphocytes have been reported in the peritoneal fluid of patients with endometriosis. Interleukin-1 (IL-1) a major product of activated macrophages and Interleukin-2 (IL-2), a product of most activated T-cells, have been postulated to play a role in the infertility associated with this disease, possibly by acting as direct embryotoxic agents. We have examined the effect of purified recombinant IL-1 and IL-2, which are not species-specific, on in vitro development of mouse embryos. Both interleukins had no effect on development to the blastocyst stage or on early stages of implantation, as measured in vitro by attachment and outgrowth of blastocysts to fibronectin-coated dishes. Moreover, co-culture of mouse embryos with activated human peritoneal macrophages had no effect on embryogenesis. We conclude that neither IL-1, nor other products of human macrophages activated by lipopolysaccharide, nor IL-2 are directly toxic to early mouse embryonic development.
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PMID:Absence of a direct effect of recombinant interleukins and cultured peritoneal macrophages on early embryonic development in the mouse. 278 73

Macrophage populations derived from Trypanosoma brucei-infected mice suppress both interleukin-2 (IL-2) production and IL-2 receptor expression. To try to identify the regulatory level by which the T-cell activation is switched off, we have analysed the potential of the suppressive macrophage-like cells to block the secretion of the accessory cell-derived T cell co-stimulator interleukin-1 (IL-1). The IL-1 secretion, however, was found to be greatly increased rather than decreased. The increased secretion was in part caused by an increased release rather than by an increased synthesis. In the presence of an in vitro trigger (lipopolysaccharide), the IL-1 secretion was increased 20-30-fold by the infection whereas the total IL-1 production increased only 1.5-2-fold. Macrophages from infected mice thus manifested a marginally increased IL-1 synthesis but released a markedly larger proportion of the synthesized monokine than normal macrophages. In the absence of an in vitro trigger, the infection caused a 10-15-fold increase in IL-1 synthesis as a consequence of an in vivo preactivation. This increase was only observed when the synthesis of prostaglandins was blocked by addition of indomethacin.
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PMID:Modulation of IL-1 production and IL-1 release during experimental trypanosome infections. 280 68

Albumin-complexed unsaturated fatty acids such as oleic acid (18:1) exerted a dose-dependent inhibitory effect on in vitro primary anti-TNP plaque-forming cell (PFC) responses to trinitrophenyl keyhole limpet haemocyanin (TNP-KLH), but did not affect primary PFC responses to trinitrophenyl lipopolysaccharide (TNP-LPS). The addition of 150 microM 18:1 at the initiation of thymus-dependent (T-D) antibody cultures inhibited the subsequent PFC response by 85%, and removal of the fatty acid after 24 hr did not reverse its inhibitory effect. By contrast, delaying the addition of 18:1 until 3 or 4 days after culture initiation abrogated its inhibitory effects. T-D antibody cultures displayed maximum production of interleukin-2 (IL-2) on the third day after culture initiation and a 24-hr exposure to 18:1 resulted in a dose-dependent inhibition of IL-2 production. Lastly, the addition of exogenous IL-2 reversed the inhibition of PFC responses in cultures transiently exposed to 18:1. These findings suggest that unsaturated fatty acids inhibit in vitro T-D PFC responses by selectively interfering with early stages of the antibody response, particularly those events leading to IL-2 production by T-helper cells.
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PMID:Unsaturated fatty acids inhibit IL-2 production in thymus-dependent antibody responses in vitro. 280 76

Culture supernatant from a human T-cell leukemia virus type I (HTLV-1)-infected cell line, DGA-1, contained a novel macrophage-activating factor (MAF). This MAF was antigenically and functionally distinct from interferon-gamma (IFN-gamma) and from granulocyte-monocyte colony-stimulating factor (GMCSF). Potential contaminants such as bacterial lipopolysaccharide (LPS), Mycoplasma spp, and HTLV-1 were not responsible for this MAF activity. The DGA-1 MAF was secreted constitutively and the cell line grew well in the absence of growth factors such as interleukin-2, mitogen, or antigen. This cell line should provide a good source of this MAF for further purification and characterization.
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PMID:A novel human macrophage-activating factor: distinction from interferon-gamma (IFN-gamma) and granulocyte-macrophage colony-stimulating factor (GMCSF). 283 73


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