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)

We studied various means of inducing avian phagocytes to migrate to the respiratory tract. No significant and consistent increases in the number of avian respiratory phagocytes (ARP) were elicited by intravenous inoculation with Escherichia coli lipopolysaccharide (LPS), Saccharomyces cerevisiae glucan (G), and Freund's incomplete adjuvant (FIA) in a water-in-oil-in-water emulsion; subcutaneous inoculation with the LPS-G-FIA homogenate; or aerosolized exposure to LPS-G-FIA, thioglycolate, and proteose-peptone. Intravenous inoculation with heat-killed Corynebacterium parvum resulted in a significant increase in the number of ARP by day 6 after inoculation; intratracheal inoculation of C. parvum effected a more rapid and higher level of phagocyte migration to the respiratory tract. Intratracheally administered E. coli induced significant migration of phagocytes to the respiratory system so that by 24 hours postinoculation, the group average number of ARP was about 50-100 times as high as the number in unstimulated control birds. None of the birds yielding high numbers of phagocytes from their respiratory tract had signs of respiratory disease.
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PMID:Cellular defense of the avian respiratory system. Influx of phagocytes: elicitation versus activation. 344 37

Glucan, a beta 1,3-linked polyglucose, is an effective macrophage activating and tumor-inhibitory agent. Previous studies indicate that glucan enhances macrophage-mediated tumoricidal activity. The present study was designed to examine the ability of glucan to enhance the production of tumor cell cytotoxic/cytostatic factor(s) designated, because of their macrophage origin, as macrophage cytotoxic factor(s) (MCF). Resting splenic macrophages in culture for 20 h secreted detectable levels of MCF. Coincubation of macrophages with bacterial endotoxin lipopolysaccharide (LPS) resulted in an enhancement of MCF production, compared to resting macrophages. Glucan-activated macrophages were more effective in producing MCF than both resting and LPS-activated macrophages. The MCF was cytotoxic to certain tumor cell lines at high concentrations and cytostatic at lower concentrations. The MCF was not significantly cytotoxic to N3T3 or BC/Sk murine fibroblasts, denoting specificity in response. Loss of MCF activity occurred following coincubation of macrophage culture supernatant with adenocarcinoma cells but not with normal fibroblasts. The MCF activity eluted at 38,000 and 84,000 daltons following column chromatographic analysis, and was heat labile at 100 degrees C but not 56 degrees C. In addition, MCF activity was diminished by protease inhibitors and antisera against tumor necrosis factor. Induction of MCF secretion may be an additional mechanism of glucan-induced antitumor activity.
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PMID:Glucan stimulates production of antitumor cytolytic/cytostatic factor(s) by macrophages. 379 56

Vertebrate lectin purified from loach egg was tested for induction of tumor lysis mediated by macrophages. Loach egg lectin lysed tumor cells but not normal spleen cells in cooperation with BCG- or glucan (TAK)-elicited peritoneal macrophages of mice. Corynebacterium parvum-, OK432-, glycogen-, lipopolysaccharide-elicited or resident macrophages were not effective. Neither loach egg lectin nor BCG nor glucan macrophages alone had a cytolytic action on tumor cells. Thus, the vertebrate lectin from loach egg is a mediator in macrophage-mediated tumor lysis, inducing binding of macrophages to target cells. This lectin-dependent macrophage-mediated cytolysis (LDMC) was inhibited by galactose, N-acetylgalactosamine, fucose, or rhamnose. These results suggest that tumor cells can be recognized via glycoconjugates on cell membrane in addition to tumor-associated antigen and that some animal lectins participate in macrophage-mediated tumor lysis.
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PMID:Macrophage-mediated tumor lysis induced by loach egg lectin. 658 20

The early cellular responses to antitumor immunomodulators and conventional inducers, especially the polymorphonuclear leukocyte (PMN) responses, were examined in the peritoneal cavity of mice to investigate their effect on primary defense mechanisms. Immunomodulators were classified into 5 groups in terms of PMN response on the basis of its duration (declining or persistent) and extent (high or low induction): 1) TAK (beta-1,3-glucan)-type (high, persistent), 2) lentinan-type (high, declining), 3) yeast mannan-type (low, declining), 4) LPS (lipopolysaccharide)-type (low, persistent), 5) others (no effect). Since the general PMN response is of the declining type, the persistence of PMN with TAK- and LPS-type immunomodulators is a characteristic of the PMN-inducing activity. With respect to the extent, TAK- and lentinan-type immunomodulators induced larger numbers of PMN and macrophages than conventional inducers. These results suggest that some types of immunomodulators have effects on the early host-defense mechanism. From the viewpoint of the general self-defense mechanism we also compared these PMN responses with those to bacteria and to tumor inoculation, and the properties of substances inducing high PMN response, i.e., those with the quality of "foreignness," are discussed.
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PMID:Early cellular responses in the peritoneal cavity of mice to antitumor immunomodulators. 673 35

The local antitumor activities and inflammation-inducing activities of various antitumor polysaccharides were examined and the relation between the two types of activity was studied. The tested antitumor polysaccharides included MG (a mannoglucan prepared from the culture fluid of Microellobosporia grisea), lentinan, bacterial lipopolysaccharide, TAK (a glucan from Alcaligenes faecalis) and their derivatives. Local antitumor activity was tested by intratumoral administration of the polysaccharides 4, 7 and 10 days after inoculation of MH134 hepatoma intradermally (id) into the abdomen of C3H/He mice. MG and its derivatives showed strong local antitumor activity. Inflammation-inducing activity was assayed by measuring foot-pad swelling and accumulation of iv-injected 51Cr-labeled spleen cells after injection of the test materials into the footpads of C3H/He mice. TAK had the strongest inflammation-inducing activity among the polysaccharides tested. No close correlation was found between the local antitumor activity and the inflammation-inducing activity.
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PMID:Different local therapeutic effects of various polysaccharides on MH134 hepatoma in mice and its relation to inflammation induced by the polysaccharides. 674 66

Following the administration of Di Luzio particulate glucan, Corynebacterium parvum, pyran (maleic anhydride vinyl ether 6), and lipopolysaccharide (Shigella) to inbred C57BL/6J mice, dose, route, and time-dependent studies were undertaken on antitumor activity and serum lysozyme levels to explore the possible relevance of serum lysozyme as a useful index of antitumor activity. Antitumor activity was assessed by measurement of the extent of loss of iv injected 125I-labeled 5-iodo-2'-deoxyuridine-labeled B16 tumor cells. Increases in serum lysozyme levels were dose-, route-, and time-dependent and varied greatly from one agent to another. The peak levels of antitumor activity were similar for all agents but were also critically dose- and time-dependent. Correlations of serum lysozyme levels and antitumor activity were inexact. The doses for peak lysozyme level increases were higher than those for peak antitumor activity. Antitumor activity peaked earlier and lasted longer than serum lysozyme level increases.
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PMID:Dose, route, and time dependence of serum lysozyme and antitumor activity following administration of glucan, Corynebacterium parvum, pyran, or lipopolysaccharide to mice. 694 57

Acetobacter methanolicus MB 70 was shown to be related to the type strain of this species MB 58/4 (IMET 10945) having the same galactan-->2)-beta-D-Gal f-(1-->3)-beta-D-Gal p-(1-->as the capsular polysaccharide (CPS) and the O-side-chain of the lipopolysaccharide (LPS). Additionally, a glucan built up of the disaccharide repeating unit-->6)-alpha-D-Glc p-(1-->2)-alpha-D-Glc p-(1-->was identified in strain MB 70. In the CPS, the polymers were present in the ratio approximately 1:1, whereas the glucan preponderated in the LPS. Bacteriophage Acm6 specific to A. methanolicus MB 70 hydrolysed selectively the glucan component of both CPS and LPS. Structural elucidation of the resulting oligosaccharides led to the identification of the phage-associated depolymerase as an endo-alpha-(1-->6)-D-glucopyranoside hydrolase.
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PMID:Structure of the capsular polysaccharide and the O-side-chain of the lipopolysaccharide from Acetobacter methanolicus MB 70, and of oligosaccharides resulting from their degradation by the bacteriophage Acm6. 751 45

The ability of grifolan (GRN), a purified fungal (1-->3)-beta-D-glucan, to induce various cytokines from macrophages was examined in vitro. Interleukin-6 (IL-6) activity in supernatants from the culture of macrophage cell line, RAW264.7 was dependent on increasing doses of GRN. The level of IL-6 induced with 500 micrograms/ml of GRN was comparable to that induced with lipopolysaccharide (LPS) 10 micrograms/ml. Enhancement of the mRNA level of IL-6 by treatment with GRN was detected by reverse transcriptase-polymerase chain reaction (RT-PCR). The effect of GRN on production of IL-6 was also observed using peritoneal macrophages from C3H/HeJ mice which did not respond to endotoxins. This data suggested that the ability of GRN to activate IL-6 production of macrophages is not due to contamination of endotoxins in the preparation. Enhanced production of cytokine by GRN was observed not only with IL-6, but also with interleukin-1 (IL-1) and tumor necrosis factor alpha (TNF alpha). In the production of TNF alpha, GRN was more effective than LPS used in this study. Other soluble or gel-forming(1-->3)-beta-D-glucans from various sources did not enhance the production of such cytokines although they are structurally similar to GRN. The above results indicate that GRN is a novel macrophage activator which augments cytokine production without dependence on endotoxins.
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PMID:Enhancement of cytokine production by macrophages stimulated with (1-->3)-beta-D-glucan, grifolan (GRN), isolated from Grifola frondosa. 753 72

The prophenoloxidase activating system, an enzyme cascade present in arthropod blood, has been shown to be involved in defense and recognition reactions. This system is converted to its active form by fungal 1,3-beta-D-glucans through binding to a plasma protein, a 1,3-beta-D-glucan-binding protein. Here the molecular cloning and carbohydrate composition of the 1,3-beta-D-glucan-binding protein from the freshwater crayfish Pacifastacus leniusculus are reported. It is also demonstrated that this protein can act as an opsonin, stimulating phagocytic uptake of yeast particles by isolated blood cells. The deduced amino acid sequence of 1,339 residues shows no significant similarity to proteins with similar functions in other animals such as the mannan-binding and lipopolysaccharide-binding proteins present in mammals. However, a short sequence motif with similarity to the active site of microbial 1,3-1,4-beta-D-glucan 4-glucanohydrolases was found to occur twice in the 1,3-beta-D-glucan-binding protein.
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PMID:Structure and biological activity of a 1,3-beta-D-glucan-binding protein in crustacean blood. 796 28

Rhizobium fredii USDA205 cells were cultured in the presence of 4',5,7-trihydroxyflavone (apigenin), a compound that has been shown to induce the nod genes and other symbiosis-related genes in R. fredii. The cell-associated polysaccharides were then extracted with hot phenol/water, separated by repetitive gel filtration chromatography, and analyzed by polyacrylamide gel electrophoresis, nuclear magnetic resonance spectrometry, high-performance anion-exchange chromatography, and gas chromatography. These analyses showed that apigenin effects a modulation in the production of some cell-associated bacterial polysaccharides: 1) The production of a glucan is severely attenuated; 2) the lipopolysaccharide O antigen is modified in composition and M(r) distribution; and 3) the ratio of two extracted polysaccharides, which are structurally analogous to group II K antigens (capsular polysaccharides), is altered. Similar effects resulted from the inclusion of host plant root extract in the growth medium.
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PMID:Production of cell-associated polysaccharides of Rhizobium fredii USDA205 is modulated by apigenin and host root extract. 801 42


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