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 role of macrophage activation in the killing of L. monocytogenes is unclear. Some studies suggest that activation for enhanced production of reactive oxygen and nitrogen intermediates may not be of central importance. Recent data have indicated an important role for interferon-gamma (IFN-gamma) induced retention of L. monocytogenes in endosomes. Data from the present study indicate that proteose peptone-elicited macrophages from DBA2/J, CD-1, and C3H/HeN mice are listericidal. Activation of these cells in vitro for 20 h by IFN-gamma (20 or 500 U/ml) increased H2O2 or nitrite production, but did not increase the number of L. monocytogenes killed during a subsequent 6-h or 7-h culture. Incubation of macrophages with IFN-gamma plus lipopolysaccharide (LPS) caused greater activation and increased the number of Listeria killed during a 6-h or 7-h culture. However, this seems primarily attributable to enhanced phagocytosis. Proteose peptone-elicited macrophages were significantly more effective than resident macrophages in preventing the escape of L. monocytogenes from endosomes into the cytoplasm. This capability was not significantly enhanced by IFN-gamma in vitro, but was enhanced by IFN-gamma plus LPS. This correlates well with the effects of these activation stimuli on killing of L. monocytogenes by proteose peptone-elicited macrophages. These results indicate that enhanced retention of L. monocytogenes in endosomes is induced by proteose peptone elicitation and that further macrophage activation in vitro by IFN-gamma does not improve listericidal activity.
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PMID:Effect of macrophage activation on killing of Listeria monocytogenes. Roles of reactive oxygen or nitrogen intermediates, rate of phagocytosis, and retention of bacteria in endosomes. 160 35

Caspase-11 (Cas11) is a cysteine protease involved in programmed cell death and cytokine maturation. Through activation of Cas1 (interleukin-1beta [IL-1beta]-converting enzyme), Cas11 is directly involved in the maturation of IL-1beta and IL-18. Apoptosis is mediated through Cas3. Given the role of apoptosis and cytokine signaling during the innate immune response in intracellular infection, we examined Cas11-deficient (Cas11(-/-)) mice during infection with Listeria monocytogenes. Cas11(-/-) and wild-type C57BL/6 mice were equally susceptible to intravenous infection with L. monocytogenes, resulting in similar bacterial burdens in tissue and similar survival rates. By contrast, enhanced susceptibility was observed in control mice on a mixed genetic 129/C57BL/DBA2 background. Cas11(-/-) and wild-type mice infected with Listeria had similar hepatic microabscess formation in terms of histologic appearance, size, and number. Apoptosis of L. monocytogenes-infected hepatocytes in vivo and in vitro in primary culture was not altered by the absence of Cas11. Serum IL-18 and IL-1beta levels were similar in Cas11(-/-) mice and controls. Endotoxin (lipopolysaccharide [LPS])-challenged Cas11(-/-) mice were deficient in the production of gamma interferon. IL-1beta responses in Cas11(-/-) were normal with intravenous administration of LPS but decreased with intraperitoneal administration. Our findings suggest that Cas11 deficiency does not impair the immune response to infection with L. monocytogenes. Apoptosis and maturation of IL-18 and IL-1beta were normal despite Cas11 deficiency. LPS-induced proinflammatory pathways are altered by the absence of Cas11. While Cas11-mediated Cas1 and Cas3 activation is crucial for cytokine maturation and apoptosis during inflammation, alternative pathways allow normal inflammatory and apoptotic responses during infection with L. monocytogenes.
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PMID:Listeria monocytogenes infection in caspase-11-deficient mice. 1195 8

We examined the anti-tumour activity of exosomes derived from dendritic cells (DCs) in combination with cyclophosphamide (CTX) and polyinosinic-polycytidylic acid sodium salt (poly I:C). DCs were pulsed with L1210 lymphocytic leukaemia cell antigen and lipopolysaccharide. The exosomes that the DCs secreted were purified. In vitro, the anti-tumour activity of exosomes was assessed by measuring their ability to induce spleen cell proliferation and the extent to which they induced spleen cells to kill L1210 cells. Poly I:C was able to induce DC maturation. DC-derived exosomes stimulated spleen cell proliferation and enhanced the cytotoxic effects of spleen cells in vitro. DC-derived exosomes, in combination with CTX and poly I:C, suppressed L1210 tumour growth in vivo and gave the greatest prolongation of survival time in tumour-bearing DBA2 mice. These findings suggest that this combination of a tumour vaccine, a conventional anti-cancer agent and a promoter of DC maturation might be a useful anti-cancer therapy.
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PMID:Anti-tumour effects of exosomes in combination with cyclophosphamide and polyinosinic-polycytidylic acid. 1909 45

Body care (grooming) is a behavioral adaptation for removing litter particles, pathogenic microbes, and parasites from animal fur and skin. It also serves as an indicator of animal health. Here a technique of direct measurement of fur cleaning has been developed. A spot of fluorescent dye applied on the back of a mouse was scanned under blue light (450 nm) immediately and rescanned 1, 2, 4, 8, and 24 hours later with a digital camera. The spot fluorescence intensity was measured using ColorScan software, which we developed using a classifier algorithm. The decrease in the spot fluorescence served as an index of fur cleaning, with significant interstrain differences in the dynamics of fur cleaning: mice of C57BL/6, CBA, CC57BR, and DD strains removed the fluorescent spot rapidly (1-2 h) whereas AKR and DBA2 mice did so slowly (24 h). To study the association between fur cleaning and stress or sickness we investigated the effect of restriction stress (for 30 min) and of the bacterial toxin lipopolysaccharide (LPS) on fur cleaning in two fast-cleaning mouse strains, CBA and C57BL/6. Restriction substantially reduced fur cleaning in the CBA mice but had no effect on the C57BL/6 mice. LPS decreased fur cleaning in a dose-dependent manner in both strains. The described technique is fairly simple and sensitive enough to estimate the effects of both stress and LPS treatment. It can be applied to study vulnerability (or resistance) to stressors, pathogenic organisms, and toxic substances.
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PMID:Novel approach to the study of fur cleaning in inbred mice: effects of genotype, stress, and lipopolysaccharide. 2037 31