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)

Gram-negative vaccines can elicit the production of tumor necrosis factor (TNF) in mice primed by muramyl dipeptide (MDP) or by its lipophilic derivative MDP-dipalmitoyl glycerol (MDP-GDP). In mice pretreated with MDP and particularly with MDP-GDP, Bordetella pertussis vaccine was shown to be more effective than typhoid vaccine. The time course of TNF production in the blood did not indicate any difference between the effect of MDP or of MDP-GDP. In both cases the cytotoxic activity reached maximal levels by 2 h after injection of the bacterial preparations and returned to normal values between 3 and 5 h after the challenge. In nude mice, high titers of circulating TNF were also produced by combined treatment with MDP-GDP and bacterial vaccine. Moreover, in tumor-bearing mice the association of MDP or of MDP-GDP to a bacterial vaccine induced a strong hemorrhagic necrosis, whereas each treatment alone was inactive. It was also found that mice were less sick when they were primed with MDP-GDP than with MDP, and when TNF was elicited by B. pertussis instead of lipopolysaccharide. Moreover, nude mice appeared more resistant to shock and to hemoconcentration than normal mice.
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PMID:Production of tumor necrosis factor in nude mice by muramyl peptides associated with bacterial vaccines. 316 34

Mo3e is a protease-sensitive membrane antigen (p75,50) selectively expressed by human monocytic cells (monocytes and U-937 cells) stimulated in vitro by exposure to a variety of activating factors, including phorbol diester compounds, bacterial lipopolysaccharide (LPS), and muramyl dipeptide (MDP)(R.F. Todd et al., J. Immunol. 135, 3869, 1985). Here we report that primary and multiply-passaged cultures of HUVEC also express the Mo3e determinant after stimulation by phorbol myristate acetate (PMA) and related inducers of protein kinase C. As measured in a radioimmunoassay of anti-Mo3e antibody binding to monolayer cultures of HUVEC, unstimulated cells bore little if any Mo3e. After culture for 4-120 hr in medium containing PMA, 4 beta-phorbol dibutyrate, 4 beta-phorbol didecanoate, or mezerein (each at a concentration of 81 nM), or 1-oleoyl-2-acetoyl-sn-3-glycerol (1 mM), HUVEC were found to selectively express the Mo3e determinant. The magnitude of expression was dependent upon the concentration of the stimulus, maximal by 24 hr, and inhibited by cycloheximide. The combination of PMA and the calcium ionophore, ionomycin, had an additive or synergistic effect on HUVEC Mo3e expression. The biologically inactive phorbol compounds 4 beta-phorbol and 4 alpha-phorbol didecanoate failed to stimulate Mo3e expression. Also inactive as inducers of HUVEC Mo3e expression were crude lymphokine and monokine supernatants, recombinant human lymphokines (interferon-gamma and interleukin-2), recombinant human monokines (interleukin-1 and tumor necrosis factor), bacterial cell wall products including LPS and MDP, pharmacologic agents that increase intracellular cyclic adenosine monophosphate (prostaglandin E2, cholera toxin, theophylline, isoproterenol and isobutylmethylxanthine), lectins (Con A and PHA), and heparin. These results indicate that Mo3e is an inducible plasma membrane antigen of not only mononuclear phagocytes but also cultured HUVEC.
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PMID:Expression of Mo3e antigen by cultured human umbilical vein endothelial cells (HUVEC) stimulated by phorbol myristate acetate (PMA) and related pharmacological inducers of protein kinase C. 334 69

The surface active material (SAM) of alveolar lining fluid has been shown to have immunologic activity. We studied the effect of SAM on monocyte-macrophage cytotoxicity against a tumor cell line. Alveolar macrophages were studied from 15 subjects without cancer. Tumor growth, as assessed by tritiated thymidine incorporation, was significantly inhibited by the macrophages alone (tumor alone median 39,401 cpm, macrophages plus tumor median 12,153 cpm, P less than 0.01). Tumor cytotoxicity was enhanced by preincubating the macrophages with lipopolysaccharide (median 37 cpm, P less than 0.01) or coincubating the tumor cells and macrophages with SAM (median 5474 cpm, P less than 0.01). Similar results were seen when using blood adherent mononuclear cells. There was increasing cytotoxicity for the adherent mononuclear cells with increasing amounts of SAM. When the various phospholipids of SAM were studied, it was found that phosphatidylcholine, sphingomyelin, and phosphatidyl glycerol all enhanced adherent mononuclear cell cytotoxicity, whereas phosphatidylinositol inhibited adherent mononuclear cell cytotoxicity. These studies suggest that SAM may have important immunoregulatory function for the alveolar macrophage.
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PMID:Enhancement of macrophage and monocyte cytotoxicity by the surface active material of lung lining fluid. 358 42

Natural and synthetic adjuvants of microbial origin were compared for their capacity to potentiate the induction of experimental autoimmune thyroiditis (EAT) with the autoantigen mouse thyroglobulin (MTg). Regardless of the immunomodulator used, severe thyroiditis was observed only in EAT-susceptible strains of the k haplotype and not in EAT-resistant strains of the d haplotype. Compared to phenol-extracted lipopolysaccharide, a potent adjuvant for enhancing EAT induction, phthalyl-substituted, detoxified lipopolysaccharide, even at doses 15- to 50-fold greater, led to only low anti-mouse thyroglobulin titers and mild thyroid infiltration. The synthetic adjuvant N-acetylmuramyl-L-alanyl-D-isoglutamine (MDP) and three of its analogs, N-acetylmuramyl-L-alanyl-D-isoglutamine-L-alanyl-D-glycerol mycolate (MDP-L-Ala-Glyc-Myc), N-acetylmuramyl-L-alanyl-D-glutamyl-(decyl)methyl ester [MDP(decyl)methyl], and N-acetylmuramyl-L-alanyl-D-glutamine-alpha n-butyl ester [MDP-(Gln)-OnBu], designated murabutide, were tested in incomplete Freund adjuvant or in saline. In incomplete Freund adjuvant, MDP-L-Ala-Glyc-Myc was inefficient in inducing EAT, murabutide induced very mild involvement, and MDP and, more so, MDP(decyl)methyl were active but to a lesser degree than CFA. When saline was used, low levels of thyroid infiltration were observed in a few of the MDP-treated animals in only one experiment, whereas no lesions were observed when murabutide was used.
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PMID:Effects of natural or synthetic microbial adjuvants on induction of autoimmune thyroiditis. 383 8

Lipoteichoic acids (LTAs) were chromatographically purified from crude phenol-water extract of whole cells of some streptococcal species, which included Streptococcus pyogenes Sv, Streptococcus mutans 6715, and Streptococcus sanguis ATCC 10556. Among these, special attention was paid to S. pyogenes LTA for analyses of chemical composition and biological activities. All LTA preparations contained equimolar amounts of glycerol and phosphorus. Chemical analyses showed that S. pyogenes LTA contained glycerophosphate, alanine, glucose, and fatty acids (as palmitic acid) at molar ratio of 1 : 0.1 : 0.1 : 0.25. The crude phenol-water extract and isolated LTA from S. pyogenes Sv were found to be mitogenic for spleen cells of BALB/c and BALB/c (nu/nu) mice, but not for thymus cells of BALB/c mice. The mitogenicity of deacylated LTA (dLTA) was significantly lower than that of LTA. It was also found that various LTA preparations possessed polyclonal B cell activation ability and adjuvant activity both in vivo and in vitro, as demonstrated by using hemolytic plaque assay. LTA, but not dLTA, induced macrophage activation which resulted in tumor cytotoxicity in mice. Limulus lysate activity of S. pyogenes LTA was approximately 1,000 fold lower than that of Escherichia coli lipopolysaccharide. These results indicate that streptococcal LTA possesses various immunobiological activities that modulate lymphoreticular system in vivo and in vitro.
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PMID:Chemical properties and immunobiological activities of streptococcal lipoteichoic acids. 389 80

Covalent modification of macromolecules can serve to alter their biological activities and is therefore frequently involved in regulation. I examined methylation of proteins and carbohydrates during development and vegetative growth in the procaryote Myxococcus xanthus. Striking differences in the patterns of protein methylation occurred when cell development was induced by nutrient deprivation on solid media and when cells were starved in liquid. In addition, a methylated, protease-resistant macromolecule which contained carbohydrate and which may have been an unusual type of lipopolysaccharide was observed on sodium dodecyl sulfate-polyacrylamide gels. A comparison of methylation patterns in various media and an analysis of the time course of methylation indicated that changes in methylation were part of the developmental pathway which includes aggregation. Induction of development in liquid by glycerol produced no changes in methylation.
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PMID:Methylation of macromolecules during development in Myxococcus xanthus. 393 24

Chemical analysis of fractions of the cell envelope of Acinetobacter sp. strain MJT/F5/199A, prepared by breakage in the French press and removal of plasma membranes, followed by sequential treatment with lysozyme and with papain, confirmed the existence of layers previously identified by electron microscopy. Outside the plasma membrane and periplasmic space, the envelope is composed of (i) a peptidoglycan-containing dense layer, (ii) an intermediate layer, (iii) a lipopolysaccharide-containing outer membrane, and (iv) an ordered array of protein subunits. A small amount of carbohydrate (3%) is found associated with protein in the fraction containing both the surface subunits and the intermediate layer. The papain-treated outer membranes contain 67% protein, 24% lipid, together with 11% lipopolysaccharide, and about 6% of non-lipopolysaccharide hexosamine. Lipid is located only in the papain-treated outer-membrane and is mainly phospholipid: 29% phosphatidyl glycerol, 30% phosphatidyl ethanolamine, and 40% cardiolipin. The principal fatty acid is C(18:1). Significant amounts of alcohols(16:1) and alcohols(18:1), which are found in Acinetobacter waxes, were recovered from the outer membrane.
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PMID:Chemical analysis of the outer membrane and other layers of the cell envelope of Acinetobacter sp. 474 22

Glycerol-teichoic acid (GTA) showed a modulatory effect on the in vitro response of murine splenocytes to the mitogens concanavalin A (Con A) and lipopolysaccharide (LPS) as measured by incorporation of 3H-thymidine. GTA inhibited the response to Con A when added prior to addition of the mitogen, while addition 24 hr after had no significant effect on the response. The degree of suppression was dose dependent in a range from 0.1-5 microgram GTA/culture. The spleen cell response to LPS was enhanced by GTA when added prior to the mitogen. Peak enhancement occurred at 1-2 microgram GTA/culture, depending on the time of addition. GTA added 24 hr after LPS produced no significant effect on mitogenesis. Addition of GTA alone to spleen cell cultures produced a slight suppression of DNA synthesis and was toxic at 10 microgram/culture if incubated at least 66 hr. GTA is bound to murine spleen cells as indicated by decreased passive hemagglutination inhibition activity of culture supernates.
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PMID:Modulation of murine lymphocyte mitogen responses by glycerol-teichoic acid. 733 39

The O-haptenic polysaccharide of Salmonella montevideo has been reported to contain glyceraldehyde at its reducing terminus. However, O-hapten preparations from a pmi galE mutant contained products of partial hydrolysis of lipopolysaccharide, which in separate experiments gave [3H]glycerol upon treatment with perchloric acid and [3H]aBH4. Further study of the O-hapten reducing terminus suggested that it was actually mannose.
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PMID:Reducing terminus of O-hapten accumulated in a Salmonella montevideo galE mutant. 746 53

Anandamide (arachidonylethanolamide), isolated from the porcine brain, and 2-arachidonyl-glycerol (2-Ara-Gl), derived from the canine gut, are two recently identified putative endogenous cannabinoid receptor ligands. Both ligands have been reported to possess binding affinity for cannabinoid receptor subtypes, CB1 and CB2. The objective of the present studies was to investigate the immunomodulatory effects of both of these ligands in B6C3F1 mouse splenocytes. 2-Ara-Gl produced a marked and dose-related inhibition of the mixed lymphocyte response, anti-CD3 mAb-induced T-cell proliferation and LPS-induced B-cell proliferation, whereas having no inhibitory effect on phorbol-12-myristate-13-acetate/ionomycin-induced cell proliferation. Interestingly, the inhibitory effects by 2-Ara-Gl on proliferation were at least dependent in part on cell density. At high cell density, 2-Ara-Gl enhanced lymphoproliferation whereas exhibiting marked inhibitory activity at low cell density. Similarly, in vitro primary immunoglobulin M antibody-forming cell responses which are dependent on high cell density also were found to be enhanced by 2-Ara-Gl. Conversely, anandamide exhibited no inhibitory effects on cell proliferative responses to stimulation by anti-CD3 mAb, lipopolysaccharide or phorbol-12-myristate-13-acetate/ionomycin treatment. Anandamide also showed no effect on the in vitro sheep erythrocyte antibody-forming cell response. Although shown previously to markedly inhibit forskolin-stimulated cyclic AMP accumulation, 2-Ara-Gl exhibited no effect on basal adenylate cyclase activity in splenocytes. Additionally, anandamide showed negligible inhibitory effects at extremely high concentrations on forskolin-stimulated adenylate cyclase activity and no effect on basal adenylate cyclase activity in splenocytes.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Effects of putative cannabinoid receptor ligands, anandamide and 2-arachidonyl-glycerol, on immune function in B6C3F1 mouse splenocytes. 747 35


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