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 production of interleukin-1 (IL-1) and tumor necrosis factor (TNF) by tumor-associated mononuclear leukocytes (TAML) and peripheral mononuclear leukocytes (PMBL) from 9 otherwise untreated patients with a variety of malignancies (lung, sarcoma, stomach, renal) was assessed. Cells were cultured for 24 hr in vitro in the presence or absence of lipopolysaccharide (LPS), and IL-1 and TNF levels were measured in culture supernatants. TNF production was comparable between TAMLs and PBMLs. However, a striking defect in IL-1 production by TAMLs was noted. There was no basal production of IL-1 and LPS-stimulated TAMLs produced only 1% the amount of IL-1 produced by LPS-stimulated PBMLs.
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PMID:Interleukin-1 and tumor necrosis factor production by tumor-associated mononuclear leukocytes and peripheral mononuclear leukocytes in cancer patients. 326 26

The effect of bacterial lipopolysaccharide (LPS), muramyl dipeptide (MDP) and their combination on the production of tumour necrosis factor by spleen cells in vitro and on tumour regression in vivo has been studied. TNF activity was detected in spleen cell supernatants and serum of mice treated with drugs, using L929 cells as targets. The combination of LPS and MDP was more effective in TNF production than each of the drugs used alone in vitro and in vivo. The injection of LPS and MDP to A/Sn mice with subcutaneous nodes of sarcoma SA-I resulted in total tumour necrosis. The treatment of mice with these drugs in water solutions was more effective, however, more toxic than the administration of LPS-treated splenocytes in MDP solution.
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PMID:[Activation of the production of the tumor-necrosis factor by the combined action of lipopolysaccharide and muramyl dipeptide in vitro and in vivo]. 331 36

Previous work identified certain components of the immunological network that had been activated following the adoptive immunotherapy of tumor-bearing mice. The present report shows that part of the activation process involves the IL-1 pathway. Tumor-associated macrophages (TAM) from C57BL/6J mice bearing the immunogenic sarcoma, MCA/76-9, and tumor-bearers injected with cyclophosphamide (CY) or CY plus the intravenous transfer of tumor-sensitized lymphocytes showed relatively high levels of intracellular (IC) IL-1, as demonstrated in the mitogenic and comitogenic assays. Gel chromatography of IC IL-1 and extracellular (EC) IL-1 from TAM induced to secrete IL-1 by stimulation with lipopolysaccharide indicated a single peak of activity of similar molecular size. The active fractions of the EC IL-1 were found to increase in activity as they were diluted to a maximum of 1/64, beyond which IL-1 activity declined. Fractions of the IC IL-1 showed no increased activity on dilution. Filtrates (less than 10 kDa) obtained on concentration of the IC and EC IL-1 samples prior to fractionation were shown to contain an activity (3-5 kDa) that inhibited the uptake of [3H]TdR by thymocytes in the mitogenic and comitogenic assays. Membrane-bound IL-1 activity also was expressed by TAM and this coincided with the previously reported peak Ia expression by these cells. TAM were also shown to induce strong proliferative responses by allogeneic lymphocyte. Systemic amplification of antitumor responses was detected in mice bearing progressing tumors and in those that had received combination therapy as measured both by increases in free IL-1 in the peritoneal cavity and IL-1 within the peritoneal macrophages. These observations indicate that in addition to enhancement of Ia expression, the IL-1 pathway also is activated and amplified systemically in this model system of tumor progression and rejection.
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PMID:Activation of the IL-1 pathway during amplification of immune responses in tumor-bearing mice. 349 84

Bacterial lipopolysaccharide (LPS) induces the release of factors into the serum which enable mice to reject experimental tumors. One such factor is tumor necrosis factor which causes acute necrosis of syngeneic sarcoma transplants in mice. Effective therapeutic use of tumor necrosis factor is limited, however, by its toxicity. We show here that the efficacy of tumor necrosis factor can be substantially increased by combining its application with low doses of LPS. Our data suggest that LPS exerts its antitumor effects by engaging more than one defense mechanism. Characteristic for the activation of a biological system is a concomitant induction of negative feedback mechanisms which antagonize the initial stimulus. Interference with the negative feedback response may substantially increase biological reactions. We show here that the blocking of two negative feedback responses occurring as a consequence of treatment with LPS, namely the production of prostaglandin E and the generation of suppressor T-lymphocytes, increases dramatically the ability of mice to reject tumor transplants. Thus, through appropriate combination of different factors one may reduce the dose of each below toxic levels and through interference with negative feedback responses increase the efficacy of antitumor reagents. We consider our findings in the context of formulating an effective immunotherapy of malignancies and as a promising step toward it.
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PMID:Combination immunotherapy of cancer in a mouse model: synergism between tumor necrosis factor and other defense systems. 379 Nov 98

Cytotoxic factor was produced from murine macrophage-like cell line, J774, after stimulation with 12-o-tetradecanoyl phorbol-13-acetate (TPA) and lipopolysaccharide (LPS). J774-derived cytotoxic factor is a glycoprotein with a molecular weight of 39,000 by gel filtration and 18,000 by SDS-PAGE, and with an isoelectric point of below 4.3. J774-derived cytotoxic factor exhibited cytotoxicity to L(S) cells, not cytotoxic to L(R) cells, and a necrotizing action against transplanted Meth A sarcoma. J774-derived cytotoxic factor and murine serum tumor necrosis factor (TNF) were identical as regards properties.
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PMID:Macrophage cell line, J774, producing a tumor necrosis factor. 380 15

The antitumor activity of the polysaccharide fraction (OPS) obtained by the acid hydrolysis of Klebsiella O3 lipopolysaccharide (KO3 LPS) isolated from the culture supernatant of the decapsulated mutant strain LEN-1 (03: K1-) against both allogeneic tumor and syngeneic tumor systems in mice was compared with that of KO3 LPS. OPS prolonged the life span of MM2-bearing C3H/He mice by intraperitoneal (i.p.) pre- and post-treatment at the doses of 100 and 1000 mg/kg. However, large amounts of OPS were needed to show the antitumor activity as compared with KO3 LPS. OPS showed no growth inhibitory activity against Meth-A sarcoma in BALB/c mice by i.p., intravenous (i.v.) or intratumoral (i.t.) administration. When 1000 mg/kg of OPS was i.p. administered once a day for 10 days, OPS significantly inhibited the tumor growth of Sarcoma-180 solid type tumor. On the other hand, KO3 LPS significantly suppressed the growth of Meth-A tumor by i.t. administration at the doses of 0.3 and 1.0 mg/kg and showed complete regression in 8 and 9 out of 10 mice, respectively. In MM2 tumor, KO3 LPS also showed complete regression in all mice post-treated by i.p. administration at the dose of 1.0 mg/kg. These results suggest that OPS has antitumor activity on the tumors used in this study, but the activity was less than that of KO3 LPS.
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PMID:Comparative studies on antitumor activity of Klebsiella O3 lipopolysaccharide and its polysaccharide fraction in mice. 406 76

Murine sarcoma virus-transformed mouse fibroblasts produce potent immunosuppressive factors (ISF) in vitro. The partially purified ISF inhibited thymocyte proliferation induced by concanavalin A or phytohemagglutinin plus lymphocyte activating factor (Interleukin 1), lipopolysaccharide-induced spleen cell proliferation, the in vitro splenic anti-sheep erythrocyte plaque-forming cell response, and the generation of alloantigen-specific cytotoxic T cells. The effect of ISF on thymocyte proliferation was not readily reversible and required only a 4-hr exposure of the thymocytes to ISF to inhibit cell proliferation. Although ISF shares several biochemical properties with a murine sarcoma virus-transformed cell-derived sarcoma growth factor (e.g., acetic acid solubility and sensitivity to dithiothreitol), the two factors could be resolved by gel filtration on Bio-Gel P-60. Two peaks of ISF activity were found with apparent molecular weights of 12,000 and 8000. The results described here support the hypothesis that at least some of the ISF obtained from the serum of tumor-bearing hosts may be released by the tumor cells themselves. In view of the potent in vitro activity of the murine sarcoma virus-transformed fibroblast-derived ISF, it is quite possible that ISF-like molecules may play a role in subverting in vivo tumor rejection processes involving the immune system.
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PMID:In vitro production of immunosuppressive factors by murine sarcoma virus-transformed mouse fibroblasts. 624 26

It has previously been demonstrated that the polycyclic aromatic hydrocarbon (PAH), benzo(a)pyrene (B[a]P), suppresses the terminal step in B-cell differentiation, resulting in a decrease in antibody production to T-dependent and B-2 T-independent antigens. The purpose of this study was to ascertain if this effect was common to carcinogenic PAHs or specific for B[a]P. The PAH 7,12-dimethylbenz[a]anthracene (DMBA) was administered to B6C3F1 female mice by ten sc injections of 0.5, 5, or 10 micrograms/g over a 2-week period (i.e., total dose of 5, 50, and 100 micrograms/g). Immune function and host resistance assays were performed 3 to 5 days following the last injection. The 10 micrograms/g dosage resulted in a marked decrease in spleen weights and spleen and bone marrow cellularity, while thymus and body weights were not significantly altered. The ability to generate B-lymphocyte colonies in vitro from spleen precursor cells was also suppressed at the 10 micrograms/g dose. Exposure to DMBA at 5 micrograms/g or greater resulted in a reduction of up to 97% in the number of IgM plaque-forming cells in response to the T-dependent antigen sheep red blood cells (SRBC). The IgG response to SRBC was similarly depressed. The IgM response to the hapten-conjugated T-independent antigens trinitrophenyl-lipopolysaccharide (TNP-LPS) (specific for B-1 cells) and trinitrophenyl (TNP)-Ficoll (specific for B-2 cells) was also depressed (88 and 97%, respectively) at 10 micrograms/g. DMBA exposure resulted in an increased susceptibility to challenge with the PYB6 transplantable sarcoma and the bacterium Listeria monocytogenes, in contrast to B[a]P exposure, which had no effect on host resistance assays. Thus, DMBA, a more potent carcinogen than B[a]P, produces a more extensive B-cell suppression than B[a]P as well as alters host resistance to tumor and bacterial challenge.
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PMID:Immunosuppression following 7,12-dimethylbenz[a]anthracene exposure in B6C3F1 mice. I. Effects on humoral immunity and host resistance. 643 12

The antitumor activity of Klebsiella 03 lipopolysaccharide (KO3 LPS) isolated from the culture supernatant against S180 sarcoma, Ehrlich carcinoma, MM2 mammary carcinoma and Meth A fibrosarcoma in mice was investigated. KO3 LPS significantly prolonged the lifespan of S180-bearing ddY mice and MM2-bearing C3H/He mice by intraperitoneal pre- or postmedication at doses ranging from 0.1 to 1.0 mg/kg. The LPS also inhibited the growth of subcutaneously inoculated Ehrlich carcinoma in ddY mice and Meth A sarcoma in BALB/c mice by intraperitoneal, intravenous or intratumoral administration. The intratumoral injection of KO3 LPS was most effective and results by the intravenous and the intraperitoneal administrations followed in effectiveness, but the administration through the subcutaneous route was hardly effective. Thus, KO3 LPS was shown to have antitumor activity on both allogeneic tumors and syngeneic tumors. It was also indicated in this study that the lifeprolonging effect of KO3 LPS on S180 ascites type tumor-bearing mice was significantly minimized by pretreatment of cyclophosphamide and that the LPS did not influence the cell viability of HeLa cells, Ehrlich cells and MM2 cells in vitro. These results suggest that the antitumor activity of KO3 LPS is provided by host-mediated actions.
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PMID:Antitumor activity of Klebsiella 03 lipopolysaccharide in mice. 650 48

Inappropriate hepatic lipogenesis, hypertriglyceridaemia, decreased fatty acid oxidation and muscle protein wasting are common in patients with sepsis, cancer or AIDS. Given carnitine's role in the oxidation of fatty acids (FAs), we anticipated that carnitine might promote FA oxidation, thus ameliorating metabolic disturbances in lipopolysaccharide (LPS)- and methylcholanthrene-induced sarcoma models of wasting in rats. In the LPS model, rats were injected with LPS (24 mg kg-1 i.p.), and treated with carnitine (100 mg kg-1 i.p.) at -16, -8, 0 and 8 h post LPS. Rat health was observed, and plasma inflammatory cytokines and triglycerides (TG) were measured before and 3 h post LPS. In the sarcoma model, rats were implanted subcutaneously with tumour, and treated continuously with carnitine (200 mg kg-1 day-1 i.p.) via implanted osmotic pumps. Tumour burden, TG and cytokines were measured weekly for 4 weeks. Carnitine treatment significantly lowered the tumour-induced rise in TG (% rise) in the sarcoma model (700 +/- 204 vs 251 +/- 51, P < 0.03) in control and carnitine groups respectively. Levels of interleukin-1 beta (IL-1 beta), interleukin-6 (IL-6) and tumour necrosis factor-alpha (TNF-alpha) (pg ml-1) were also lowered by carnitine in both LPS (IL-1 beta: 536 +/- 65 vs 378 +/- 44: IL-6: 271 +/- 29 vs 222 +/- 32; TNF-alpha: 618 +/- 86 vs 367 +/- 54, P < or = 0.02) and sarcoma models (IL-1 beta: 423 +/- 33 vs 221 +/- 60; IL-6: 222 +/- 18 vs 139 +/- 38; TNF-alpha: 617 +/- 69 vs 280 +/- 77, P < or = 0.05) for control and carnitine groups respectively. We conclude that carnitine has a therapeutic effect on morbidity and lipid metabolism in these disease models, and that these effects could be the result of down-regulation of cytokine production and/or increased clearance of cytokines.
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PMID:Effects of L-carnitine on serum triglyceride and cytokine levels in rat models of cachexia and septic shock. 757 64


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