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)

Monoclonal antibody H3/5-47 was raised against a human melanoma metastasis and recognizes an antigen expressed in the endothelial cells of all normal human organs as assessed by immunohistochemistry. Antigen expression is higher in venous than in capillary or arterial endothelia; capillary endothelia of different microvascular beds, such as skin, lung, gut or liver, may express varying amounts of this antigen. H3/5-47 antigen expression in the endothelia of diseased tissues (inflammatory diseases, neoplasias) largely reflects its expression pattern in normal tissues. As might be anticipated, the highest expression of H3/5-47 antigen is found in resting adult cutaneous and hepatic cavernous venous hemangiomas. In contrast, psoriatic vessels, characterized by hypertrophy and fenestrations, tend to express H3/5-47 antigen at a much lower density. In human umbilical vein endothelial cells, half the single donor cases show no expression of H3/5-47 antigen, while the rest express the antigen at relatively low densities in about half the cells. Treatment with interferon-gamma or thrombin, but not interleukin-1, lipopolysaccharide, endothelial cell growth factor or phorbolester, either enhances or induces de novo expression in cultured human umbilical vein endothelial cells within 24h; maximum expression of H3/5-47 antigen is induced by interferon-gamma within 72 h. H3/5-47 antigen is not similar to other antigens inducible in human umbilical vein endothelial cells such as HLA-DR, ICAM-1, HECA-452, Leu13, MCP-1 or gamma-IP-10. It is not specifically expressed in the endothelium as it may also recognize certain epithelia, peripheral nervous tissue and bone marrow-derived cell populations.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Monoclonal antibody H3/5-47 recognizes an inducible cell surface antigen expressed differently in endothelium of normal and diseased tissues and in vitro. 162 58

Tissue factor (TF) which initiates clotting process can be expressed by stimulated endothelial cells (EC). TF is an apolipoprotein requiring an association with phospholipids (PL) in order to become active. Also PL constitute an important storage pool of polyunsaturated fatty acids (PUFAs) in EC which can be modulated by diet or cell medium supplementation. In order to test the effect of such manipulation upon TF activity, we have pre-enriched human EC cultures with different fatty acids of nutritional interest. TF was evaluated after 4 h of thrombin stimulation by using a chromogenic method. Without additional stimulating agents, these acids have no effect on the basal level of TF. Eicosapentaenoic and docosapentaenoic acids appeared to be ineffective at the stimulated TF level. Only adrenic acid (22:4(n-6)) has been found to significantly enhance TF activity of thrombin-stimulated endothelial cells. Other TF inducers were also tested after 22:4(n-6) enrichment. An increase tendency of TF expression was found only with tumor necrosis factor, whereas interleukin-1 beta, lipopolysaccharide and especially phorbol myristate acetate stimulations were not significantly modified. The priming effect of adrenic acid on thrombin stimulated TF expression might involve alterations of signal transduction pathways rather than modifications of apolipoprotein III environment. Adrenic acid, which is a prostacyclin inhibitor, appears to be potential prothrombotic agent.
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PMID:Priming effect of adrenic acid (22:4(n-6)) on tissue factor activity expressed by thrombin-stimulated endothelial cells. 164 92

Antithrombotic effect of recombinant human thrombomodulin (TM) on experimentally induced thrombosis in mice was studied. The soluble recombinant human TM (TMD 123), which was expressed in Chinese hamster ovary cells and purified from the conditioned medium, prolonged thrombin clotting time for mouse plasma in a dose-dependent fashion. Thrombosis was induced by the injection of lipopolysaccharide (LPS) from E. coli into a lateral tail vein of mice and was identified as disseminated intravascular coagulation (DIC) syndrome by hematological and histological examinations. Simultaneous injection of TMD 123 with LPS into another lateral tail vein of mice significantly corrected the hematological abnormalities compatible with DIC, and also corrected the histological abnormalities i. e. fibrin deposition and decrease of cellular TM in the target organs including kidney, liver and lung. These results indicate that recombinant human TM is a potent antithrombotic agent and that this would be an expectative anticoagulant for DIC or thrombosis in man.
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PMID:[Antithrombotic effect of recombinant human thrombomodulin on experimentally induced thrombosis in rats]. 165 29

Thrombomodulin (TM) exists not only in endothelial cells but also in circulating plasma as soluble heterogeneous fragments. A release mechanism of soluble TM antigen from endothelial cells was investigated. Cultured human umbilical vein endothelial cells released about 0.6% of total cellular TM antigen into conditioned medium during 24 h. The release of TM antigen was not influenced by addition of various concentrations (0.01-5.0 microM) of monensin, which inhibits intracellular transport of secretory proteins, though the secretion of plasminogen activator inhibitor-1 from the cells was inhibited. The release of TM antigen was not increased when total cellular TM level increased 1.3- or 1.4-fold relative to control cells after stimulation with 0.1-1.0 U/ml thrombin or 3 mM dibutyryl cAMP, respectively. Exposure of endothelial cells for 6 h to mixture of 1 microM N-formyl-methionyl-leucyl-phenylalanine (FMLP) and 100 ng/ml lipopolysaccharide (LPS) decreased cellular TM level by 30% relative to control cells without increase in the TM release. The FMLP and LPS-stimulated leukocyte treatment of the cells increased the release of TM antigens into the medium in a time-dependent manner and the increased release of TM antigen paralleled the extent of cell damage as measured by 51Cr release. Hydrogen peroxide treatment of the cells increased the release of TM antigens into the medium in a time- and concentration-dependent manner. The increased release of TM antigen by hydrogen peroxide also paralleled the extent of cell damage.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Soluble thrombomodulin antigen in conditioned medium is increased by damage of endothelial cells. 165 69

Thrombomodulin is an essential cofactor for the activation of the anticoagulant protein C by thrombin. We have identified the expression of thrombomodulin messenger RNA (mRNA) and protein in peripheral blood monocytes. While untreated monocytes expressed thrombomodulin mRNA by Northern blot analysis, lipopolysaccharide-treated cells had decreased mRNA expression. Thrombomodulin antigen was shown in the cytoplasm and on the surface of monocytes by immunohistochemical staining, and thrombomodulin activity was shown on the surface of intact monocytes. One population of synovial lining cells that normally expressed mononuclear phagocyte antigens also expressed thrombomodulin in both noninflamed osteoarthritic synovium and in inflamed rheumatoid arthritis synovium. However, these cells did not express another endothelial protein, von Willebrand factor. We conclude that both circulating and tissue mononuclear phagocytes are capable of expressing thrombomodulin.
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PMID:Thrombomodulin expression by human blood monocytes and by human synovial tissue lining macrophages. 166 Mar 24

Rat serosal mast cells were evaluated for their capacity to generate a nitric oxide-like factor by two bioassays: inhibition of platelet aggregation and stimulation of mast cell guanylate cyclase. Incubation of mast cells with human washed platelets, both treated with indomethacin, inhibited thrombin-induced platelet aggregation which was potentiated by superoxide dismutase and reversed by oxyhaemoglobin. When mast cells alone were stirred at 1000 rpm, a time dependent increase in the levels of their cGMP but not cAMP was observed. Preincubation of mast cells with NG-monomethyl-L-arginine significantly enhanced E. coli lipopolysaccharide-evoked histamine release. Our results show that mast cell histamine release can be modulated by an intrinsically generated nitric oxide-like factor.
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PMID:Rat mast cells synthesize a nitric oxide like-factor which modulates the release of histamine. 171 38

1. Incubation of smooth muscle cells (SMC) from bovine aorta for 3 min with human washed platelets treated with indomethacin (10 microM) promoted a cell number-related inhibition of platelet aggregation induced by thrombin (40 mu ml-1). This inhibition was not attributable to products of the cyclo-oxygenase pathway for the SMC were also treated with indomethacin (10 microM). 2. The inhibitory activity of the SMC on platelet aggregation was enhanced by incubating the SMC with E. coli lipopolysaccharide (LPS, 0.5 micrograms ml-1) for a period of 9 to 24 h. This effect was attenuated when cycloheximide (10 micrograms ml-1) was incubated together with LPS. Cycloheximide did not prevent the inhibitory activity of the non-treated cells. 3. The inhibition of platelet aggregation obtained with non-treated or LPS-treated SMC was potentiated by superoxide dismutase (SOD, 60 u ml-1) and ablated by oxyhaemoglobin (OxyHb, 10 microM). Preincubation of the SMC with NG-monomethyl-L-arginine (L-NMMA, 30-300 microM) for 60 min prevented their antiaggregatory activity. This effect was reversed by concurrent incubation with L-arginine (L-Arg, 100 microM) but not with D-arginine (D-Arg, 100 microM). 4. Exposure of the non-treated SMC (5 x 10(5) cells) to stirring (1000 r.p.m., 37 degrees C) for 10 min led to a significant increase in their levels of guanosine 3':5'-cyclic monophosphate (cyclic GMP) but not adenosine 3':5'-cyclic monophosphate (cyclic AMP). L-NMMA (300 microM) attenuated the increase in cyclic GMP induced by stirring but did not affect the basal levels of cyclic GMP in the cells.5. These findings support the idea that non-treated or LPS-treated cultured SMC can produce an NO-like factor. Production by the latter requires protein synthesis as evidenced by blockade with cycloheximide. This NO-like factor may play a role in the auto-regulation of smooth muscle cell reactivity through a cyclic GMP-dependent mechanism.
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PMID:Nitric oxide from vascular smooth muscle cells: regulation of platelet reactivity and smooth muscle cell guanylate cyclase. 172 27

Rat serosal mast cells (MCs, 85-90% pure), obtained from peritoneal washing of Wistar albino rats, produced a significant amount of superoxide anions (O2.-) as measured by the increase in absorbance due to the reduction of ferricytochrome c; they were also able to generate a nitric oxide (NO)-like factor, as measured by two bioassay systems: i) inhibition of platelet aggregation and ii) stimulation of MCs guanylate cyclase. Incubation of MCs with human washed platelets resulted in an inhibition of thrombin-induced platelet aggregation which was proportional to cell number. The inhibitory activity of MCs was potentiated by substances which preserve NO (superoxide dismutase, SOD), and reversed by compounds which inactivate NO (oxyhaemoglobin, oxyHb) or which inhibit its synthesis (NG-monomethyl-L-arginine, MeArg). Mechanical stimulation of MCs produced a time-dependent increase in the levels of their cGMP but not cAMP; this increase was enhanced by E. coli lipopolysaccharide (LPS). NO generators such as sodium nitroprusside (NaNp) also augmented the levels of cGMP in MCs. NaNp inhibited in a dose-dependent manner the release of histamine evoked by compound 48/80 (0.5 microgram/ml), but not by the O2.--generating system (xanthine-xanthine oxidase), suggesting a bidirectional regulation of histamine release afforded by O2.- and NO.
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PMID:Mast cells as a source of superoxide anions and nitric oxide-like factor: relevance to histamine release. 172 22

An experimental model incorporating cultured endothelial cells (EC) was used to study the "factor VIII bypassing" activity of prothrombin complex concentrates (PCC), a property exploited in the treatment of hemophiliacs with alloantibodies to factor VIII. Two PCC preparations were ineffective as stimuli of tissue factor expression by EC. However, incubation with a combination of PCC plus endotoxin (lipopolysaccharide, LPS) or tumor necrosis factor (TNF) induced much greater tissue factor expression than was seen in response to either substance alone. PCC expressed an additional direct procoagulant activity at the EC surface, which could not be attributed to either thrombin or factor Xa, and which was diminished by an anti-tissue factor antibody. Therefore factor VIIa, which was detectable in both PCC preparations, likely provided this additional direct procoagulant activity at the EC surface. We also excluded the possibility that coagulation proteases contained in or generated in the presence of PCC are protected from inactivation by AT III. Therefore, PCC can indirectly bypass factor VIII by enhancing induced endothelial tissue factor expression, and also possess direct procoagulant activity, probably mediated by factor VIIa.
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PMID:The factor VIII bypassing activity of prothrombin complex concentrates: the roles of factor VIIa and of endothelial cell tissue factor. 180 20

Cryopreserved human monocytes have been examined for their procoagulant and profibrinolytic capacities on lipopolysaccharide (LPS) stimulation, when given the possibility to act upon fibrinogen in heparinized plasma. As shown by the appearance of fibrinopeptide A, indicating thrombin action on the fibrinogen molecule, and by the appearance of D-Dimer, indicating the action of plasmin on fibrin, it is apparent that LPS-instructed monocytes give rise to fibrin which is subsequently lysed. Thus, delineation (fibrin formation) appears to be followed by fibrin removal (restitution).
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PMID:Lipopolysaccharide-instructed, cryopreserved, human monocytes sequentially convert plasma fibrinogen to fibrin and lyse the fibrin formed. 188 14


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