Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: UNIPROT:P43026 (lipopolysaccharide)
 62,215 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Endotoxin (lipopolysaccharide, LPS) induces endothelial injury in arterial vessels. Fibronectin is known to be involved in cell attachment and wound repair. The present study was designed to elucidate the effect of LPS on the production and distribution of fibronectin in relation to injury and repair in rat aortic endothelium. Male Sprague-Dawley rats were sacrificed for ultrastructural and immunocytochemical evaluations at 1, 3, 6, 24, and 48 hr after a single intravenous injection of 1.5 or 3 mg/kg body weight E. coli LPS. Apparent morphological signs of endothelial injury, including cell detachment, denudation, cell death, and edema were observed 1-48 hr after injection. Parietal thrombosis and leukocyte diapedesis were also observed in the aorta. A profound increase in subendothelial fibronectin was found following LPS treatment. However, no distinct change in intracellular fibronectin was observed in the same endothelium until 24 hr after injection. Using horseradish peroxidase (HRP) and anti-fibronectin-HRP antibody as tracers, LPS was also found to increase permeability and extravasation of plasma proteins (fibronectin) of the aortic endothelium. The increase of subendothelial fibronectin possibly resulted from increased influx and sequestration of plasma fibronectin. This increase may provide a firm substratum for reendothelialization after vascular injury.
 ...
PMID:Endotoxin-induced endothelial injury and subendothelial accumulation of fibronectin in rat aorta. 199 87

A simple and rapid enzyme immunoassay for specific antibodies in chicken egg yolk is described. As a model system, the levels of anti-Salmonella IgG in the yolk of eggs obtained from various produce retailers were compared. Polyester cloth coated with Salmonella typhimurium lipopolysaccharide was used to capture specific egg yolk antibodies, which were then detected using an anti-chicken IgG-peroxidase conjugate. This assay, requiring less than 30 min to complete, revealed considerable differences in the relative levels of anti-Salmonella IgG in the egg yolks. Anti-Salmonella IgG levels were generally lower in eggs obtained from large produce retailers than in eggs obtained from a small local farm. This assay may provide a rapid and economical means of monitoring the levels of Salmonella contamination in chicken rearing facilities.
 ...
PMID:Rapid enzyme immunoassay of chicken egg yolk IgG. 205 4

Interaction of bacterial lipopolysaccharide (LPS) with monocytes stimulates production of a variety of mediators that are involved in the pathogenesis of septic shock and wound repair. We report here the mechanisms of LPS uptake and intracellular distribution of LPS in human monocytes. Ficoll-Hypaque-purified peripheral mononuclear cells (PBMC) were exposed to LPS from rough Escherichia coli (J5) or to biotin-conjugated LPS (biotin-LPS) from smooth E. coli (0111:B4), or to fluorescein isothiocyanate-conjugated LPS of E. coli (055:B5) at 37 degrees C for various times and processed for electron microscopy, immunocytochemistry, and flow cytometry. Monocytes were identified by the presence of numerous cytoplasmic peroxidase-positive granules or by monoclonal antibodies against monocyte. LPS micelles were identified by their specific bilayer structure, staining of horseradish peroxidase reaction product, or colloidal gold using biotin-LPS or a monoclonal antibody to LPS. Binding of LPS to cell surface was observed 5 min after incubation with LPS. Intracellular localization of LPS micelles was found 30 min following exposure to LPS. Prolonged incubation with LPS increased intracellular LPS. Intracellularly, LPS micelles were found in large membrane-bound vacuoles, in small vesicles, and in the cytoplasm and nucleus. They were also observed in association with the cytomembrane of various organelles. The overall results indicate that LPS may be taken up by monocytes by direct passive diffusion through ruptures of plasma membrane, pinocytosis, and phagocytosis, involving specific and/or nonspecific binding, and suggest that peripheral blood monocytes play an important role in clearance of LPS; that LPS may have broad effects on cell functions; and that the nonspecific binding to various cytomembranes may be destructive to cell organelles and cells in general.
 ...
PMID:Ultrastructural and immunocytochemical study of the uptake and distribution of bacterial lipopolysaccharide in human monocytes. 211 60

Polyester cloth coated with polymyxin B was used to capture Salmonella typhimurium lipopolysaccharide antigens which were then quantitatively or qualitatively assayed using a specific antibody-peroxidase conjugate. This simple, rapid method can be used to assay a large number of samples by employing a large sheet of the polymyxin-coated cloth onto which multiple samples can be blotted. The method is reproducible and economical, since polymyxin B is relatively inexpensive, stable and available in pure form.
 ...
PMID:Use of polymyxin-coated polyester cloth in the enzyme immunoassay of Salmonella lipopolysaccharide antigens. 228 82

T cells from genetically susceptible mice developing experimental autoimmune thyroiditis (EAT) proliferate in response to restimulation with mouse thyroglobulin (MTg) in vitro. The in vitro-activated cells adoptively transfer EAT as well as differentiate into cells cytotoxic for syngeneic thyroid monolayers. To examine the kinetics of T cell subset infiltration and distribution in situ after adoptive transfer, we applied the avidin-biotin-peroxidase labeling technique to thyroid sections, utilizing rat monoclonal antibodies followed by a biotinylated rabbit anti-rat antibody. Female CBA donor mice were immunized with MTg and lipopolysaccharide. Their spleen cells were obtained 7 days later, cultured with MTg, and transferred into recipient mice. The thyroids were removed on Days 7, 10, and 14 after transfer and serially sectioned. The early phase of transferred EAT showed a higher percentage of L3T4+ cells compared to Lyt-2+ cells, yielding a ratio of 2.3 and total T cells of about 35%. By Day 10, both T cell subsets had increased to a total of about 56%. However, the relative increase was greater in the Lyt-2+ subset; the nearly doubled percentage was statistically significant, resulting in a downward shift in the subset ratio to 1.7. Little change in the in situ distribution was seen on Day 14. The percentages of F4/80+ (macrophage) population in lesions examined on Days 10 and 14 were fairly constant and B cell involvement was minimal. These findings illustrate the pathogenic role of both T cell subsets in adoptively transferred EAT and the time-dependent changes in their relative proportions leading to thyroid gland destruction.
 ...
PMID:In situ analysis of T cell subset composition in experimental autoimmune thyroiditis after adoptive transfer of activated spleen cells. 229

Tumor necrosis factor-alpha (TNF) has been implicated strongly as a principal mediator in the pathogenesis of septic shock. The authors investigated the in vivo production of TNF in CBA/J and CD-1 mice that had been primed by an intraperitoneal injection of complete Freund's adjuvant followed 2 weeks later by an intraperitoneal injection of lipopolysaccharide (LPS). TNF bioactivity peaked in both the ascites and plasma one hour after challenge, and TNF mRNA expression in the ascites cells peaked 30 minutes after LPS. After the induction of bioactivity, an interstitial pulmonary neutrophilic infiltrate occurred that was quantitated both morphometrically and by a myeloperoxidase (MPO) assay. Peripheral blood neutrophilia and lymphopenia developed after the LPS injection (PMNs: control, 46 +/- 2%; LPS, 65 +/- 3%; Lymphs control, 53 +/- 2%; LPS, 37 +/- 3%). Treatment with dexamethasone (Dex) completely inhibited the pulmonary neutrophilic infiltrate as measured by the (MPO) assay. Because Dex will inhibit the production of several cytokines, anti-TNF antiserum was given to mice at the same time as the LPS challenge to assess specifically the role of TNF in inducing these changes. This antiserum partially blocked the pulmonary neutrophil infiltrate, and completely blocked the peripheral blood changes at one hour after LPS. These data demonstrate that TNF plays an important role in the early pathophysiologic alterations that occur after systemic exposure to LPS.
 ...
PMID:Role of tumor necrosis factor-alpha in lipopolysaccharide-induced pathologic alterations. 229 50

Human macrophages obtained from circulating monocytes matured in vitro by culture for seven days in hydrophobic flexible teflon bags were successfully fused with murine myeloma NS1 cells. Six of 20 clones, selected for their adherence properties, were further studied. All possessed human chromosomes (mean number ranging from 4 to 14 depending on the clones studied), exhibited non-specific esterases (but no peroxidase activity) and expressed CD14 antigen and C3 receptors (but no MAX-1 antigen). Moreover, the hybridomas retained phagocytic activity and high interferon plus lipopolysaccharide-activable cytolytic activity against tumor cells.
 ...
PMID:Establishment and characterization of somatic hybrids between human differentiated macrophages and mouse myeloma NS1 cells. 240 83

The outer membrane proteins of Legionella pneumophila serogroups 1 to 8 were prepared from broken cells by selective solubilization using sodium lauryl sarcosinate. The isolated proteins were separated by sodium dodecyl sulfate-polyacrylamide gel electrophoresis and transferred to nitrocellulose sheets. Rabbit antisera against each of the eight serogroups of L. pneumophila were obtained by immunizing each animal with live bacteria. The transferred proteins were revealed using these antisera and peroxidase-labeled swine anti-rabbit immunoglobulins. Antigenic determinants common to all eight serogroups were found in at least three outer membrane antigens (19, 29, and 45 kilodaltons (kDa)). However, cross-absorption experiments revealed that these three antigens were immunologically related, but not identical among serogroups. The antigenic relationships observed with two of these three antigens correlated well with cross-reactions observed in immunofluorescence. When a monoclonal antibody directed against L. pneumophila serogroup 1 lipopolysaccharide was used to reveal a blot of serogroup 1 outer membrane antigens, the 29- and 45-kDa bands appeared. This demonstrates a strong association between lipopolysaccharide and outer membrane proteins.
 ...
PMID:Antigenic variability of the outer membrane antigens of Legionella pneumophila serogroups 1 to 8. 244 23

Bacterial lipopolysaccharide (LPS) has previously been shown to enhance a number of chemoattractant-induced responses by human neutrophils. The possible role of elastase, a neutral protease with broad substrate specificity, in neutrophil-mediated vascular injury of a variety of diseases prompted us to examine a) whether or not LPS enhances the direct chemoattractant-induced secretion of elastase, b) the quantitative requirements of LPS and chemotactic factors, and c) some structural requirements of LPS for this effect. Our results show that LPS at 10 ng/ml and above, enhanced formyl-methionyl-leucyl-phenylalanine-induced neutrophil secretion of elastase, as well as secretion of myeloperoxidase and vitamin B12-binding protein. This effect was independent of cytochalasins or surface stimulation, and thus may occur during chemotactic factor stimulation in vivo. LPS also enhanced neutrophil secretory responses to the complement fragments C5a, C5a des arg, and, to a lesser degree, to leukotriene B4 and platelet-activating factor. This enhancement effect appeared to require the presence of the lipid A moiety and/or parts of the core polysaccharide but not the O-antigen portion of the LPS molecule. Our findings identify a possible LPS-dependent mechanism of neutrophil elastase-mediated tissue injury in Gram-negative infections.
 ...
PMID:Bacterial lipopolysaccharide enhances chemoattractant-induced elastase secretion by human neutrophils. 245 79

Purified O chain of Brucella abortus was passively attached to polystyrene to differentiate antibody responses of cattle vaccinated with B abortus strain 19 from those of naturally infected cattle. In the indirect assay, using O polysaccharide as antigen, a single serum dilution was used and mouse monoclonal antibody to bovine L chain conjugated with horseradish peroxidase was the detection reagent. Measurable antibody was not found in sera of vaccinated cattle, except for 3 sera from cattle that were persistently infected with strain 19. Sera from 25 cattle infected with pathogenic strains contained antibody on the basis of results of indirect enzyme immunoassay, using smooth lipopolysaccharide or O chain as antigens, or results of competitive enzyme immunoassay, using the O-chain antigen. Results in sera from calves with experimentally induced Yersinia enterocolitica serotype 0:9 infection or inoculated with a low dose of B abortus strain 2308 were comparable with those in sera of cattle that were vaccinated with strain 19. The data correlated with those from competitive enzyme immunoassay, using one serum dilution and horseradish peroxidase-conjugated mouse monoclonal antibody to smooth lipopolysaccharide. On the basis of results of the indirect enzyme immunoassay, all sera (except those samples obtained before inoculation) contained antibody to smooth lipopolysaccharide.
 ...
PMID:Enzyme-linked immunosorbent assay for differentiation of the antibody response of cattle naturally infected with Brucella abortus or vaccinated with strain 19. 246 11


<< Previous 1 2 3 4 5 6 7 8 9 10 Next >>