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)

Hypertension is a known risk factor for the development of atherosclerosis, which is characterized by the abnormal accumulation of low-density lipoprotein and other plasma-borne macromolecules. The goal of this study was to measure accumulation of a plasma-borne macromolecular marker, horseradish peroxidase (HRP; 44 kDa), in the aortic intima and media of chronically hypertensive rats. HRP transport in 2-yr-old spontaneously hypertensive rats (SHR) was compared with that in age-matched Wistar-Kyoto rats (WKY) under conditions in which blood pressures were not significantly different during the 15-min HRP circulation. Intimal accumulation and medial HRP concentration profiles were obtained from methacrylate-embedded sections after reaction with 3,3'-diaminobenzidine and H2O2. Data were analyzed using a mathematical model of macromolecular transport to quantify the permeabilities of endothelium and internal elastic lamina (IEL). Chronic hypertension increased endothelial permeability without a change in IEL permeability. An apparent convective flux of HRP into the intima of SHR raised intimal HRP to a concentration higher than that of HRP in the plasma. Our results suggest that the intimal accumulation of plasma-borne macromolecules from pressure-driven convection is normally minimized by an intact endothelium. Similar changes resulted from acute injury by lipopolysaccharide, suggesting endothelial injury could account for transport changes associated with hypertension. After either chronic or acute endothelial damage, transport of macromolecules into the intima increases, but the IEL continues to retard transport of macromolecules beyond the intima, resulting in increased intimal accumulation.
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PMID:Macromolecular transport in the arterial intima: comparison of chronic and acute injuries. 913 37

Cholate-extracted lipopolysaccharide (LPS) antigens from thermophilic campylobacters were captured on polymyxin-coated polyester cloth. The captured antigens were detected by sequential reactions with rabbit anti-Campylobacter antibody, anti-rabbit IgG peroxidase conjugate and chromogenic peroxidase substrate. A polyclonal rabbit antibody elicited against a single Campylobacter-jejuni strain detected the reference strains of the twenty most frequently isolated thermophilic campylobacters in the Lior serotyping scheme. Moreover, LPS antigens of six C. Jejuni Penner serotypes fractionated by sodium dodecyl sulfate-polyacrylamide gel electrophoresis and examined by immunoblotting were recognized by four antisera prepared against homologous and heterologous Penner serotypes. The results suggest the potential application of polymyxin-cloth enzyme immunoassay for rapid detection of thermophilic campylobacters where monoclonal antibodies can be raised to possible common LPS epitopes.
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PMID:Immunological detection of lipopolysaccharide antigens of thermophilic campylobacters captured on polymyxin-coated polyester cloth. 915 52

The ability to form tight junctions and the paucity of fluid phase endocytosis showed by brain microvacular endothelial cells (BMECs) make up the structural basis of the blood-brain barrier (BBB). Most studies on cultured BMECs focused on intercellular junctions, whereas endocytosis received lesser attention. We studied endocytosis of horseradish peroxidase in primary and passage 1 and 2 BMEC cultures from rat brain as well as in human umbilical vein endothelial cell (HUVEC) culture. Endocytic activity was also analyzed in passage 1 BMECs treated with lipopolysaccharide (LPS, 1 microg/ml for 4 h), which mimics BBB disruption in bacterial meningoencephalitis. The percent of cytoplasmic area occupied by endocytic profiles (vesicles <70 nm and vacuoles >70 nm) and their mean number per cell were significantly lower in primary and passaged BMEC than in HUVEC cultures. The area and number of endocytic profiles significantly increased in BMECs after exposure to LPS. BMECs cultured under standard conditions may be a suitable model for studying the mechanism of increased fluid phase endocytosis in certain diseases and injury states.
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PMID:Endocytosis of horseradish peroxidase by brain microvascular and umbilical vein endothelial cells in culture: an ultrastructural and morphometric study. 925 Jun 20

Previous studies showed that chronic endotoxemia induces thickening of the alveolar wall of rabbits. The present study examines cellular changes associated with this process and attempts to define the role of PMN in this response. Rabbits received i.v. injections of either Escherichia coli lipopolysaccharide (LPS) or saline (control), 2-3 times weekly, for 28 weeks. Peripheral blood mature and immature polymorphonuclear leukocyte (PMN) cell counts were determined on Wright-stained blood smears. Lung histological analysis was performed by both light and electron microscopy. FITC-Maclura pomifera was used to identify type II cells and diaminobenzidine tetrahydrochloride-H2O2 was employed to localize peroxidase. The results show that the LPS-induced neutrophilia is associated with an increase in the circulating band cells which is consistent with active bone marrow release. PMN in the pulmonary microvessels display structural features characteristic of phagocytosis and active macromolecule synthesis. Endothelial cells, adjacent to these PMN, show numerous coated pits and large inclusions suggestive of endocytosis. The LPS-induced thickening of the alveolar wall is associated with leukocyte migration into the interstitial and alveolar spaces. Some interstitial PMN are fragmented and surrounded by dispersed elements of the connective tissue, while others appear activated and are closely associated with hyperactive fibroblasts and alveolar type II cells. The number of alveolar type II cells has increased twofold. These results show that chronic endotoxemia in rabbits causes structural changes in PMN, endothelium, interstitium, and epithelium. PMN structural changes are consistent with enhanced functional properties and their close association with modified regions of the lung parenchyma suggest that PMN play an important role in the process of this lung injury and repair.
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PMID:Neutrophil structural changes associated with chronic endotoxemia and lung injury. 936 88

Intraventricular macrophages encompass the supraependymal, free-floating, and epiplexus (Kolmer) cells; the supraependymal cells lie in close apposition to the ventricular ependyma, the epiplexus cells are closely associated with the choroid plexus epithelium, and the free-floating cells are at a variable distance from the epithelial surface. Although the three cell types are regarded as one cellular entity, the epiplexus cells preponderate. On scanning electron microscopy, the epiplexus cells display diverse morphological forms, ranging from round to bipolar to stellate, and bear a variable number of cytoplasmic processes. Transmission electron microscopy shows the presence of large numbers of lysosomes. The phagocytic nature of epiplexus cells is shown by their intense staining for nonspecific esterase and active uptake of tracers, e.g., horseradish peroxidase and rhodamine isothiocynate, administered intravenously or intraperitoneally. The mode of entry of these tracers in the cerebral ventricles is by way of transepithelial transport. In rats, the population of intraventricular macrophages increases steadily after birth until 17 days of age; thereafter, their cell population remains relatively unchanged. The early upsurge is attributed to proliferation of residential cells and/or influx of circulating monocytes/stromal macrophages through the process of "emperipolesis." The immunophenotypic features of intraventricular macrophages are consistent with other mononuclear phagocytes being immunoreactive for OX-42, OX-18, OX-6, and OX-1 and ED1 for the detection of CR3 receptors, MHC class I and II antigens, leucocyte common antigen, and macrophage antigen, respectively. The expression of these antigens is noticeably enhanced following the injection of lipopolysaccharide (LPS) into postnatal rats. Remarkably, the intraventricular macrophages are induced to express MHC class II (Ia) antigen after LPS or interferon-gamma injections. Furthermore, the expression of transferrin receptors as detected with OX-26 is also upregulated after these treatments. Epiplexus cells are also elicited to display a de novo expression of nitric oxide synthase-like immunoreactivity following intracerebral injection of LPS. They also respond vigorously to a single nonpenetrative blast. Results of our series of studies suggest that, besides their primary function as scavenger cells, the intraventricular macrophages partake in possible immunological responses and iron regulation in the ventricular system or the brain as a whole.
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PMID:Origin, nature, and some functional considerations of intraventricular macrophages, with special reference to the epiplexus cells. 955 Jan 36

An indirect enzyme-linked immunosorbent assay (ELISA) for Brucella abortus antibodies detection in bovine milk and serum samples was validated. The assay use B. abortus smooth lipopolysaccharide as antigen, immobilized on a polystyrene matrix; milk diluted 1:2 or serum diluted 1:50, in a buffer containing divalent cation chelating agents EDTA and EGTA (ethyleneglycol-bis-aminoether-N,N,N',N'-tetraacetic acid) to reduce non-specific reactions; and a mouse monoclonal antibody specific for an epitope of bovine IgG1, conjugated with horseradish peroxidase. A total of 2646 sera and 2119 milk samples from cows older than 24 months were obtained from 12 brucellosis-free herds for at least the previous 5 years. Milk samples were obtained in parallel with serum samples. The remaining 527 serum samples were from dry cows. All cattle were vaccinated with B. abortus strain 19 between 3-10 months of age. Five hundred and fifty-two milk samples and 562 serum samples were obtained from 6 infected herds with abortions where B. abortus was isolated at least once no more than 6 months before sampling. The complement-fixation test (CFT) on serum samples was considered the gold standard. Serum samples were also tested with the official screening test: the buffered plate antigen (BPA) test. The cut-off point was determined using receiver-operating characteristic (ROC) analysis. For milk samples, it was fixed at 36 percent positivity (PP) giving a sensitivity of 99.6% with a 95% confidence interval (CI) of 98.6-99.9%. The specificity was 99.1% (CI 98.9-99.4%). For serum samples, the cut-off was fixed at 53 PP giving a sensitivity of 99.6% (CI 98.6-99.9%) and a specificity 98.6% (CI 98-99%). The BPA test showed a relative sensitivity of 99.6% (CI 98.6-99.9%) and a relative specificity of 98.6% (CI 98.1-99%). Our results indicate that the indirect ELISA is a highly sensitive and specific test and can be adapted to process a large number of samples.
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PMID:Evaluation of an indirect ELISA for the diagnosis of bovine brucellosis in milk and serum samples in dairy cattle in Argentina. 978 76

Recent evidence suggests an interaction between immune, enteric neural and fibroblasts in the regulation of intestinal function. Earlier, we have reported that lipopolysaccharide (LPS) induced cell proliferation, collagen synthesis and production of proinflammatory mediators in lamina propria fibroblasts. In this report, we investigated the change in transepithelial resistance (TER) as a marker of epithelial barrier function by lipopolysaccharide (LPS) and its modulation by human small intestinal lamina propria fibroblasts (HSILPF). Epithelial cells incubated with LPS alone did not show any change in the TER at any concentration or prolonged exposure. However, co-cultivation of epithelial cells with lamina propria fibroblasts which had been exposed to LPS resulted in a rapid decrease in TER by 2 hr. The decrease in the TER was continued till 8 hr followed by returning to the basal level by 24 hr. The supernatant of LPS-treated HSILPF was less effective in causing a fall in the TER than HSILPF itself. The fall in TER was accompanied by loosening of tight junctions as depicted by increased penetration of horse radish peroxidase (HRP) across the epithelial cells from the apical to the basal side. Increased incorporation of 3[H]thymidine (tritiated thymidine) in epithelial cells was observed at 48 hr in the presence of LPS-treated HSILPF. The decrease in TER during the early time period in epithelial cells was abrogated to 70% by incubating the LPS-treated HSILPF and the conditioned medium of LPS-treated HSILPF with anti-TNFalpha antibody, and not with antibody to other cytokines like IL1alpha, IL1beta, IL6 and IL8. Overall, these results suggest that TNFalpha produced by HSILPF in response to LPS as a soluble form cause a decrease in the TER and loosening of tight junctions, and such early changes in the epithelial barrier may contribute to local inflammation in the gut.
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PMID:Modulation of barrier function of small intestinal epithelial cells by lamina propria fibroblasts in response to lipopolysaccharide: possible role in TNFalpha in inducing barrier dysfunction. 1048 May 48

The relationship between gender and alcohol-induced liver disease is complex; however, endotoxin is most likely involved. Recently, it was reported that estriol activated Kupffer cells by upregulation of the endotoxin receptor CD14. Therefore, the purpose of this work was to study how estriol sensitizes Kupffer cells. Rats were given estriol (20 mg/kg ip), and Kupffer cells were isolated 24 h later. After addition of lipopolysaccharide (LPS), intracellular Ca2+ concentration was measured using a microspectrofluorometer with the fluorescent indicator fura 2, and tumor necrosis factor-alpha was measured by ELISA. CD14 was evaluated by Western analysis. One-half of the rats given estriol intraperitoneally 24 h before an injection of a sublethal dose of LPS (5 mg/kg) died within 24 h, whereas none of the control rats died. Mortality was prevented totally by sterilization of the gut with antibiotics. A similar pattern was obtained with liver histology and serum transaminases. Translocation of horseradish peroxidase was increased about threefold in gut segments by treatment with estriol. This increase was not altered by treatment with nonabsorbable antibiotics. On the other hand, endotoxin levels were increased to 60-70 pg/ml in plasma of rats treated with estriol. As expected, this increase was prevented (<20 pg/ml) by antibiotics. In isolated Kupffer cells, LPS-induced increases in intracellular Ca2+ concentration, tumor necrosis factor-alpha production, and CD14 were increased, as previously reported. All these phenomena were blocked by antibiotics. Therefore, it is concluded that estriol treatment in vivo sensitizes Kupffer cells to LPS via mechanisms dependent on increases in CD14. This is most likely due to elevated portal blood endotoxin caused by increased gut permeability.
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PMID:Estriol sensitizes rat Kupffer cells via gut-derived endotoxin. 1048 93

Using two-dimensional electrophoresis, we have recently identified in human bronchoalveolar lavage fluid a novel protein, termed B166, with a molecular mass of 17 kDa. Here, we report the cloning of human and rat cDNAs encoding B166, which has been renamed AOEB166 for antioxidant enzyme B166. Indeed, the deduced amino acid sequence reveals that AOEB166 represents a new mammalian subfamily of AhpC/TSA peroxiredoxin antioxidant enzymes. Human AOEB166 shares 63% similarity with Escherichia coli AhpC22 alkyl hydroperoxide reductase and 66% similarity with a recently identified Saccharomyces cerevisiae alkyl hydroperoxide reductase/thioredoxin peroxidase. Moreover, recombinant AOEB166 expressed in E. coli exhibits a peroxidase activity, and an antioxidant activity comparable with that of catalase was demonstrated with the glutamine synthetase protection assay against dithiothreitol/Fe3+/O(2) oxidation. The analysis of AOEB166 mRNA distribution in 30 different human tissues and in 10 cell lines shows that the gene is widely expressed in the body. Of interest, the analysis of N- and C-terminal domains of both human and rat AOEB166 reveals amino acid sequences presenting features of mitochondrial and peroxisomal targeting sequences. Furthermore, human AOEB166 expressed as a fusion protein with GFP in HepG2 cell line is sorted to these organelles. Finally, acute inflammation induced in rat lung by lipopolysaccharide is associated with an increase of AOEB166 mRNA levels in lung, suggesting a protective role for AOEB166 in oxidative and inflammatory processes.
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PMID:Cloning and characterization of AOEB166, a novel mammalian antioxidant enzyme of the peroxiredoxin family. 1052 24

A double antibody sandwich enzyme immunoassay (EIA) for chlamydial antigen detection was developed using a monoclonal antibody against lipopolysaccharide (LPS) of Chlamydia trachomatis as a coating antibody. Polyclonal rabbit antiserum against partially purified antigen from elementary body (EB) antibody and horse-radish peroxidase conjugated goat anti-rabbit antibody were used as the primary and secondary antibody respectively. The developed EIA could detect protein of partially purified EB at the lowest concentration of 250 ng/ml. The assay was evaluated against the cell culture (CC), DNA hybridization assay (PACE2 system: Gen-Probe, San Diego, CA, USA) and a commercial enzyme immunoassay (kEIA) (Bioquest, NSW, Australia). The sensitivity, specificity, positive and negative predictive values of the developed EIA (dEIA) were 87, 96.2, 80, 97.7 for the specimens from females and 90.9, 90.7, 71.4, 97.5 for the specimens from males repectively. Cross reaction was not found with Escherichia coli, Acinetobacter anitratus, beta-Streptococcus group A, Enterobacter spp, Enterococcus, Lactobacillus spp, Neisseria spp, but it was found with Candida albicans and herpes simplex virus type 1. The developed EIA can be applied successfully for both genders, particularly males. The cost per test is less than those for CC, kEIA and PACE2.
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PMID:Development of EIA for detection of Chlamydia trachomatis in genital specimens. 1102 74


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