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)

Lipid X, a precursor in the biosynthesis of lipid A, has been claimed to possess most of the immunostimulatory activity but none of the toxicity of endotoxin. However, recent work shows that synthetic lipid X can be contaminated with small amounts of N,O-acylated disaccharide-1-phosphate (H. Aschauer, A. Grob, J. Hildebrandt, E. Schuetze, and P. Steutz, J. Biol. Chem. 265:9159-9164, 1990). Because the impurities themselves exhibit immunostimulatory properties, it was necessary to establish whether chemically pure synthetic lipid X exhibits any of the endotoxinlike biological activities previously attributed to the native compound extracted from the Escherichia coli MN7 mutant. In the present study, two batches of synthetic lipid X were used: batch A contained the contaminating disaccharide, and batch B was pure lipid X. Batch A, previously believed to be pure on the basis of spectroscopic and microanalysis data, induced murine peritoneal macrophages to secrete tumor necrosis factor, interleukin-1, and prostaglandin E2 at a minimal dose of 10 micrograms/ml in vitro. Batch B, further purified by Sephadex LH 20 chromatography, was found virtually inactive in these in vitro assays. Furthermore, batch A was pyrogenic in rabbits at a dose of 0.05 mg/kg, whereas batch B was not pyrogenic at doses of up to greater than or equal to 2 mg/kg. However, both batches were equally tolerated by galactosamine-loaded mice at doses of up to 100 mg/kg. Surprisingly, while only batch A protected neutropenic mice against lethal infection with Pseudomonas aeruginosa (50% effective dose, 12.4 mg/kg), both batches were equally protective against infection with herpes simplex virus type 1 in mice and guinea pigs, even when lipid X was administered therapeutically. Interestingly, both batches of lipid X blocked endotoxin-induced expression of monocyte procoagulant activity and priming of human neutrophils for superoxide anion release. Similarly, both batches protected galactosamine-sensitized mice from otherwise lethal endotoxemia when administered prophylactically or simultaneously with the lipopolysaccharide challenge. Thus, our findings suggest that chemically pure lipid X (batch B) is devoid of the immunostimulatory properties of lipid A or endotoxin. Rather, it behaves as a competitive inhibitor of lipopolysaccharide. We conclude, therefore, that previous studies which attributed immunostimulatory activities to any batch of synthetic lipid X should be interpreted with caution.
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PMID:Immunostimulatory, but not antiendotoxin, activity of lipid X is due to small amounts of contaminating N,O-acylated disaccharide-1-phosphate: in vitro and in vivo reevaluation of the biological activity of synthetic lipid X. 164 70

Direct virus inactivation of tachyplesin I and related isopeptides, which are antimicrobial peptides isolated from the hemocytes of the horseshoe crab (Tachypleus tridentatus and Limulus polyphemus), was examined against several viruses. Vesicular stomatitis virus (VSV) was inactivated by incubation with tachyplesin I and its isopeptides. Influenza A (H1N1) virus was slightly inactivated by tachyplesin I, whereas herpes simplex virus 1 and 2, adenovirus 1, reovirus 2 and poliovirus 1 were resistant to inactivation. The inactivation of VSV by tachyplesin I depended on the concentration, the time and the temperature of incubation. Pretreatment of tachyplesin I with trypsin or lipopolysaccharide of gram-negative bacteria entirely abolished the antiviral activity. Electron microscopy of VSV treated with tachyplesin I showed naked and damaged virions. These data suggest that tachyplesin I directly inactivates the VSV by destroying its envelope subunits.
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PMID:Direct virus inactivation of tachyplesin I and its isopeptides from horseshoe crab hemocytes. 166 45

Macrophages from patients with breast cancer showed an impairment of their antiviral activity. The capability to hinder herpes simplex virus type 2 replication of macrophages from healthy donors and from patients with breast cancer was compared to the in-vitro treatment with Escherichia coli lipopolysaccharide (LPS). The LPS showed a dose-dependent effect on the different macrophage populations studied. Nevertheless, macrophages from healthy donors appeared to be more sensitive to LPS in comparison with macrophages from the patients under our observation. On these cells LPS treatment was not able to modify the antiviral property, when these macrophages were differentiated in autologous serum.
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PMID:Modulation of the intrinsic antiviral activity by Escherichia coli endotoxin in macrophages from patients with neoplasia. 185 Apr 54

Previous work has shown that splenic macrophages derived from herpes simplex virus (HSV)-resistant C57BL/6 mice undergo a persistent HSV infection which is characterized by the continuous release of infectious virus particles from a small subpopulation of infected cells. Treatment of persistently infected macrophages for 2 weeks with lipopolysaccharide (LPS) resulted in an increase of HSV yield and in virus-induced cytopathic effects. HSV was also reactivated by treatment of macrophage cultures with lipid A or tumour necrosis factor (TNF). Like macrophages of C57BL/6 origin, cells from LPS-hyporesponsive C3H/HeJ mice could be persistently infected with HSV. These cells were resistant to LPS-induced virus reactivation. The results show that macrophages derived from C57BL/6 mice are rendered susceptible to lytic HSV infection by treatment with LPS or TNF. Thus, these substances may interfere with persistent HSV infection which can be established due to genetically controlled properties of the host.
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PMID:Stimulation of macrophages by endotoxin results in the reactivation of a persistent herpes simplex virus infection. 216 12

Immune splenocytes were obtained from C3H/He mice, which had been inoculated with herpes simplex virus (HSV) type 1 by the corneal route 6 or 12 days previously, and restimulated by lipopolysaccharide-induced lymphoblasts infected with HSV. These cells were either not treated or treated with anti-L3T4 antibody plus complement/anti-Lyt-2 antibody plus complement, and were transferred to subconjunctiva of mice with HSV corneal infection. Adoptive transfer of non-treated cells diminished corneal ulcers, when the splenocytes were transferred from mice inoculated 12 days previously. This effect was reduced by depletion of Lyt-2 bearing cells, but not reduced by depletion of L3T4 bearing cells. Adoptive transfer of splenocytes from mice inoculated 6 days previously did not diminish corneal++ ulcers. These findings demonstrate that HSV specific cytotoxic T lymphocytes (CTL) play an important role in the late phase of recovery from HSV corneal infection.
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PMID:[Effects of T cell subsets on mouse herpetic keratitis]. 222 Apr 89

It is generally agreed that endotoxins from Gram-negative bacteria play a modulatory role on several macrophage functions. The intrinsic activity versus herpes simplex virus type 1 and type 2 of Kupffer cells, peritoneal and alveolar macrophages, harvested from normal and tumour-bearing rats, was evaluated. Moreover, the effects of different intravenous treatments with S. enteritidis endotoxin were investigated. The antiviral activity of peritoneal, alveolar macrophages and Kupffer cells from tumour-bearing rats is definitely impaired but it appears to be positively modulated by in-vivo administration of S. enteritidis lipopolysaccharide (LPS).
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PMID:Role of Salmonella enteritidis lipopolysaccharide on anti-HSV activity of macrophages from different anatomical sites. 256 62

Treatment of mice by intraperitoneal inoculation of pertussis vaccine or lipopolysaccharide extracted from B. pertussis will effect resistance to rabies virus, encephalomyocarditis virus, Semliki Forest virus, and Herpes simplex virus. Our previous observations indicated that treatment of C3H/HeN (+/nu) and BDF1 mice with pertussis vaccine injected i.p. five days prior to a mouse adenovirus lethal dose i.p. challenge elicited resistance to clinical disease and death. Susceptibility returned to a portion of the test population 35 days after pertussis vaccine treatment. The pertussis vaccine induced resistance developed in athymic (nude) mice also; however, the population succumbed to infection 35 days later. Titration of pertussis vaccine with respect to induction of resistance indicated the median effective dose (ED50) was approximately 25 micrograms dry weight. This report describes the antiviral activity of acellular components extracted from pertussis vaccine. Extraction of B. pertussis cells with 1.0M NaCl and ammonium sulfate fractionation (20-40% saturation) of the extract resulted in an acellular preparation that induced resistance to lethal dose mouse adenovirus infection. The resistance inducing activity was retained after treatment of the extract with detergent (GAF Emulphogene BC 720) to remove lipopolysaccharide and adsorption to alum gel. Comparison of endotoxin content of pertussis vaccine acellular fractions, polysaccharide fraction and purified lipopolysaccharide suggested that endotoxin probably plays a role in the induction of resistance. The endotoxin content of a Emulphogene-treated preparation that protected 80% of a test population was 39 ng. The lipopolysaccharide extracted from Escherichia coli, Vibrio cholerae, Salmonella typhimurium, and Salmonella minnesota did not induce a resistant state seven days after administration; however, lipopolysaccharide extracted from B. pertussis induced a resistant state.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Immunomodulation by Bordetella pertussis: antiviral effects. 287 9

Cytotoxic T lymphocyte (CTL) responses of splenic T cells from C57BL/6 B6) mice and mutant H-2Kbm1 (bm1) mice to haptenic (trinitrophenyl [TNP] ) and herpes simplex virus (HSV) determinants in the context of an allogenic (wild-type or mutant) H-2Kb molecule were analyzed in a modified limiting dilution system. In the B6-anti-bm1TNP mixed leukocyte reaction (MLR), estimated frequencies for precursors of CTL clones that lysed bm1TNP targets ranged from 1/120 to 1/400; in the bm1-anti-B6TNP MLR, estimated frequencies of precursors of CTL clones that lysed B6TNP targets ranged from 1/500 to 1/1,300. Estimated frequencies for precursors of CTL clones that lysed the respective unmodified and TNP-modified allogeneic targets were two- to three-fold lower. Lytic specificity patterns determined by split-well analysis showed that at least 20-30% of the generated CTL populations (selected for a high probability of clonality) in both MLR displayed allorestricted lysis of TNP-modified concanavalin A blast targets. In the B6-anti-bm1HSV MLR, estimated frequencies for precursors of CTL clones that lysed bm1HSV targets ranged from 1/70 to 1/300; in the bm1-anti-B6HSV MLR, estimated frequencies for precursors of CTL clones that lysed B6HSV targets ranged from 1/300 to 1/1,200. Again, estimated frequencies for precursors of CTL clones that lysed the respective noninfected and virus-infected allogeneic targets were two- to fourfold lower. Of the CTL populations selected for a high probability of clonality at least 30-60% displayed allorestricted lysis of virus-infected lipopolysaccharide blast targets in both MLR. It is concluded that a large fraction of clonally developing CTL populations stimulated with TNP-modified or HSV-infected allo-H-2Kb-bearing cells displayed an allorestricted pattern of recognition. It was further evident that the estimated frequencies of splenic precursors that generated allorestricted CTL clones was two- to threefold higher than the estimated frequencies of precursors that gave rise to the respective alloreactive CTL populations.
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PMID:Allorestricted cytotoxic T cells. Large numbers of allo-H-2Kb-restricted antihapten and antiviral cytotoxic T cell populations clonally develop in vitro from murine splenic precursor T cells. 299 16

C3H/He and BALB/c mice were inoculated with herpes simplex virus (HSV) by corneal or intraperitoneal route. The mouse splenocytes were analyzed to determine the level and mode of cytotoxic T lymphocyte (CTL) induction by a cytotoxicity test, using HSV-infected L929 cells and 3T3 cells as the target cells. To enhance the activities of CTL, mouse splenocytes were restimulated by lipopolysaccharide-induced lymphoblasts (LPS-blasts) infected with HSV before assay. HSV infection by both corneal and intraperitoneal routes induced H-2 restricted T lymphocyte responses specific for HSV. This CTL response became detectable on day 6 in mice with herpetic keratitis and on day 4 with intraperitoneal infection, but 10 days after infection the CTL activities of both groups reached the same level. A high response level persisted as long as 28 days. These results suggest that the protective mechanism in herpetic keratitis is similar to the mechanism in intraperitoneal infection.
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PMID:Immunological studies of herpetic keratitis: induction of cytotoxic T lymphocytes in mouse splenocytes. 387 28

The course of infection with herpes simplex virus type 1 (HSV-1) in peritoneal macrophages, phytohemagglutinin (PHA-)stimulated (T-)lymphocytes and lipopolysaccharide (LPS-)stimulated (B-)lymphocytes of NMRI-mice was studied by means of electron microscopy. Non-stimulated as well as thioglycolate-stimulated macrophages were investigated; lymphocytes were derived both from HSV-1-sensitized and non-sensitized animals. The morphological characteristics of the abortive infection in macrophages and T-lymphocytes and of the productive infection in B-lymphocytes are described. No differences were observed between stimulated and non-stimulated cells or cells of sensitized and non-sensitized animals.
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PMID:Electron microscopic studies of herpes simplex virus type 1 infection of macrophages, T- and B-lymphocytes of mice. 625 May 15


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