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)

A cell wall fraction (F8) extracted by boiling sodium dodecylsulfate at 4 % from Brucella abortus 99S was used with oil adjuvant to vaccinate groups of ten guinea-pigs, at doses equivalent to 1 X 10(9) and 1 X 10(10) bacteria, once or twice at 3 month intervals. H38 vaccine, a total cell vaccine from formalized B. melitensis 53 H38, was used as a reference, at doses 3 X 10(8) and 3 X 10(9) bacteria. These doses were chosen since they have about the same vaccinal activity in mice being respectively equal to 10 and 100 mice optimal dose (MOD). One extra-group of guinea-pigs received two injections of 100 microgram of smooth-lipopolysaccharide (LPS-S) of B. melitensis 16M, in adjuvant. Control group received the adjuvant only. Guinea-pigs were challenged 3 months after the last vaccination with 5,000 colony-forming units of B. abortus 544, and autopsied 40 days later. The spleen and 8 lymph nodes were cultured: a guinea-pig is considered as protected if no Brucella was found in any sample. Protection afforded by the two vaccines is dose-dependent. H38 vaccine gives a better protection (infected 24 %) than F8 (46 %) since a higher dose is needed to obtain the same level of protection: i. e., 100 MOD of F8 is about equal to 10 MOD of H38 (35 and 37 % respectively). Contrary to what was previously shown in mice, recall does not improve the immunity and LPS-S does not vaccinate at all.
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PMID:Immunogenic activity of a cell wall fraction extracted from Brucella abortus in guinea-pigs. 11

Endotoxin (lipopolysaccharide, LPS) and LPS antibody in the blood were studied in 61 cases of ulcerative colitis (U.C.) by radioimmunoassay. Lysozyme (LZM) concentration was also studied by the turbidimetric method. As a result, it was found that the blood LPS value as well as serum LZM concentration reflects the clinical observations. The case of endotoxemia in the active phase group showed a positive correlation between the LPS value and LZM concentration. LPS antibody which could not be detected in many cases of the active phase, had a high titer in cases of remission with a long history of the disease. These results would suggest that in U.C. with damaged intestinal mucosal barrier, LPS originating from intestinal flora enters into the blood and aggravates the disease and further that this invading LPS releases LZM into the blood. The same studies were performed on 7 cases of Crohn's disease and the same result was obtained.
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PMID:A study of endotoxemia in ulcerative colitis and Crohn's disease. I. Clinical study. 15 Feb

The intestinal mucosal barrier of rabbits was damaged by carrageenan-induced ulceration of the colon, superior mesenteric artery occlusion (SMAO) and hemorrhagic shock and the values of Endotoxin (lipopolysaccharide, LPS) were determined by radioimmunoassay and the concentration of lysozyme (LZM) by the turbidimetric method. As a result, endotoxemia was observed in 13 out of 15 carrageenan rabbits, and in all of the SMAO and hemorrhagic shocked rabbits. Serum LZM concentration rose with time in all cases. As to the correlation of LPS and LZM, they changed almost in parallel in carrageenan rabbits, SMAO and hemorrhagic shock. LPS value and LZM concentration in blood were also determined in LPS injected rabbits. It was confirmed that injected LPS increased the LZM concentration of blood. On the basis of these results, it can be concluded that destruction of intestinal mucosal barrier permits an invasion of LPS into blood and then releases LZM into the blood stream.
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PMID:A study of endotoxemia in ulcerative colitis and Crohn's disease. II. Experimental study. 15 86

The biological specificity of the endotoxin receptor on platelet membranes was examined. The binding indices of platelets in experimental endotoxemia which was induced by intravenous administration of endotoxin (Lipopolysaccharide of E. coli, Difco) to rabbits were found to be 30% of the control at 60 min after the injection. The result suggests that the endotoxin receptor of platelets was already occupied. The binding indices of human platelets were measured after pretreatment with pharmacologically active substances which were assumed to effect platelet activity. The binding of LPS to platelets showed competitive inhibition at pharmacologically effective doses, but other substances merely inhibited platelet activity. One interpretation is that there is a common receptor on platelet cell membranes for lipopolysaccharide of E. coli and endotoxin. The sensitivity to endotoxin in vivo and binding indices of platelets were examined in rabbits and guinea pigs since their response to endotoxin is almost opposite with regard to sensitivity. The binding indices of platelets from rabbits and guinea pigs showed a positive correlation with the endotoxin sensitivity. Those findings indicate that platelets play a key role in vivo in the clinical course of endotoxemia.
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PMID:Endotoxin receptor site. II. Specificity of endotoxin receptor of platelets and sensitivity to endotoxin in vivo. 15 87

The maturation level of the B-lymphocyte subpopulations involved in trinitrophenyl (TNP)-specific immunological tolerance in adult mice induced by the injection of trinitrobenzenesulfonic acid (TNBS) was investigated using in vitro antigen-specific and nonspecific polyclonal stimulation. The maturity of the B-cell subsets being studied was defined by the antigen or polyclonal activator which evoked a response. Thus, the thymic independent (TI-1) antigen TNP-lipopolysaccharide (TNP-LPS) and the polyclonal stimulant LPS were used to activate immature, neonatal-type B lymphocytes, whereas mature, adult-type B cells were responsive to the TI-2 antigen, TNP-Ficoll, and the nonspecific activator, purified protein derivative (PPD). Whereas unresponsiveness in TNP-LPS-reactive (immature) B cells 4 d after TNBS treatment was previously shown to be the result of functional deletion, partially reversible receptor blockade was detected in this study early after tolerogen treatment. By the 24-h point, tolerance was irreversible, as assessed by 24-h of antigen-free incubation and cocultivation of tolerant cells with control splenocytes. Tolerance was induced more rapidly in immature, TI-1 B cells than in mature TI-2 B lymphocytes. B lymphocytes reactive to TNP-Ficoll were also less susceptible to receptor blockade. Using LPS as a nonspecific probe for immature B cells, 60% tolerance in high affinity TNP-specific cells was induced within 12 h of TNBS treatment, and complete unresponsiveness by 24 h. In contrast, no significant decrease in response to the mature B-cell activator, PPD, occurred until day 2. Furthermore, the 50% tolerance level was achieved in TNP-specific LPS-reactive B cells by 100 times less tolerogen than required for PPD-responsive cells. Thus, TNBS-induced unresponsiveness in cells reactive to TNP-LPS is initially a result of reversible receptor blockade which leads within 4 d to functional deletion. Immature, TI-1 B lymphocytes, which give polyclonal responses to LPS and antigen-specific responses to TNP-LPS, are rendered tolerant to TNBS more rapidly and at lower tolerogen does than mature, TI-2 mouse B cells which react polyclonally to PPD and specifically to TNP-Ficoll. Moreover, these data show that both the immature and the mature B lymphocyts with these characteristic tolerance susceptibilities and specific and nonspecific immune response patterns are present in the adult mouse spleen.
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PMID:The induction of hapten-specific immunological tolerance and immunity in B lymphocytes. VI. Differential tolerance susceptibility in adult spleen as a function of B-cell maturation level. 15 60

The capsular polysaccharide of Klebsiella pneumoniae (CPS-K) type 1, Kasuya strain, induces interferon production in the blood of mice when injected intravenously. CPS-K resembles bacterial endotoxin (lipopolysaccharide) in the time pattern of interferon production, with peak levels 2h after injection. CPS-K on a weight basis exhibits a more potent interferon-inducing effect than lipopolysaccharide. The active substance responsible for the interferon-inducing activity of CPS-K is the neutral CPS-K antigen which is antigenically distinct from the O antigen and from acidic CPS-K (the type-specific capsular antigen). Neutral CPS-K from the Kasuya strain has been already found to exhibit a strong adjuvant effect on antibody responses to various antigens in mice. Preparations of neutral CPS-K from other strains of K. pneumoniae, of which adjuvant action is only very weak, exhibit interferon-inducing activity similar to the preparation from the Kasuya strain. Heterologous and homologous tolerance to re-induction of interferon is produced by a prior injection (one each) of LPS, neutral CPS-K, and acidic CPS-K. No simple correlation exists between the inducing and tolerogenic capabilities of these substances.
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PMID:Interferon production in mice by the capsular polysaccharide of Klebsiella pneumoniae. 16 21

Immobilized antigen-antibody complexes are able to inhibit the mitogenic response of murine spleen cells to the B-cell mitogen 8-bromo-3',5'-cyclic guanosine monophosphoric acid. This this inhibition is dependent on intact Fc fragments in the immobilized complexes. Soluble complexes do not mediate this inhibition. When lipopolysaccharide (lps) activation of B cells was studied, it was found that the mitogenic response was inhibited at all times tested between 2 and 7 days of culture. Also, the LPS-induced mitogenesis of nude spleen cells was inhibited by immobilized complexes, indicating that suppressor T cells probably play no significant role in the inhibition. Immobilized complexes inhibit polyclonal antibody responses in a serum-free system and in the presence of normal mouse serum, but are unable to inhibit in the presence of fetal calf serum (FCS). If nu/nu spleen cells are used, however, the FCS does not block the ability of the complexes to inhibit the polyclonal response. It is suggested that that antigen-antibody complexes under appropriate conditions may bind to B lymphocytes via their Fc receptors and trigger a central "off" signal which blocks proliferation and consequently antibody production.
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PMID:Fc receptor-mediated inhibition of murine B-lymphocyte activation. 18 99

Normal human serum was shown to inhibit the mitogenic effects of bacterial lipopolysaccharide and Con A on mouse spleen lymphocytes and reduce the in vitro antibody response to SRBC by these cells. Furthermore, it was demonstrated that immune suppression occurred without loss of lymphocyte viability. Fractionation of normal human serum resulted in isolation of several immunoenhancing and immunoinhibitory fractions. Electrophoretic analysis of the immunoinhibitory fractions revealed a complex array of serum proteins. The most prominent proteins on polyacrylamide electrophoresis stained for both proteins and carbohydrate. The heterogeneity of immunoinhibitory fractions were further substantiated by their differential susceptibility to trypsin, periodate, and 2-mercaptoethanol treatment. Heterogeneity of the fractions was also shown to be related to difference in their biologic activity as expressed in their effects on mitogenicity and immunogenicity of LPS in mouse splenic cultures. This study lends evidence to the consideration that normal human serum contains several immunoregulatory factors with differing biochemical characteristics and cellular sites of action.
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PMID:Isolation and characterization of immunoregulatory factors from normal human serum. I. Preliminary biochemical and biological characterization of immunosuppressive factors. 19 Mar 15

The structure of lipopolysaccharide from a heptose-less mutant of Escherichia coli K-12 has been investigated. Lipopolysaccharide isolated from 32P-labeled cells was treated with mild alkali to yield two separable components: [OH-LPS]-I (approximately 70%) and [OH-LPS]-II (approximately 30%). Mild acidic treatment of [OH-LPS]-I gave mainly a product which was identified as (4-O-phosphoryl-N-beta-hydroxymyristyl-D-glucosaminyl)-beta(1 leads to 6)-N-beta-hydroxymyristyl-D-glucosamine 1-phosphate (Compound I). Further acidic hydrolysis of both [OH-LPS]-I and [OH-LPS]-II yielded as the main product (4-O-phosphoryl-N-beta-hydroxymyristyl-D-glucosaminyl)-beta(1 leads to 6)-N-beta-hydroxymyristyl-D-glucosamine (Compound II). The structures of the above products were deduced by a combination of compositional analyses, sensitivity to phosphomonoesterase, rates of hydrolysis of the phosphate groups and alkali-catalyzed beta elimination of the phosphate residues following appropriate oxidation of hydroxyl groups. These studies together with work reported in the accompanying papers have led to the identification of two species of lipopolysaccharide in the E. coli strain both of which contain a single glucosamine dissacharide unit but differ in having monosubstituted phosphate or pyrophosphate groups at the glycosidic position. Each species of lipopolysaccharide also appeared to be heterogeneous with respect to the number of esterified fatty acyl groups.
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PMID:Structure of the lipopolysaccharide from an Escherichia coli heptose-less mutant. I. Chemical degradations and identification of products. 22 86

The effects of endotoxin (lipopolysaccharide [LPS]) on the pathogenesis of canine endotoxin shock were compared with those of LPS which had interacted with polymyxin B sulfate prior to administration. Both LPS and polymyxin B-modified LPS caused comparable early decreases in aortic blood pressure, leukocyte and platelet numbers, and serum complement levels. However, in dogs receiving polymyxin B-modified LPS the late hypotensive phase was significantly ameliorated and lethality was significantly decreased. These data indicate that polymyxin B-modified LPS, though significantly less lethal than unmodified LPS, was capable of major interactions with several components of the humoral defense system, and support the concept that such interactions are not determinative in the pathogenesis of canine endotoxin shock.
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PMID:Polymyxin B sulfate modification of bacterial endotoxin: effects on the development of endotoxin shock in dogs. 22 76


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