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C Galanos

Publications and source records attributed to C Galanos.

At least 91 records · Page 5Linked to original sources
PubMed1989

Identification and percentage frequency of isolated non-parenchymal liver cells (NPLC) in the mouse.

The aim of the present study was to identify non-parenchymal liver cells (NPLC) in B10.D2 mice and to determine their percentage frequency. The isolation of NPLC was carried out using the collagenase/pronase technique. Using functional techniques (latex phagocytosis, immunocytochemical detection of surface-bound and intracytoplasmic antigens) and morphological methods (light and electron microscopy), the following cell types were identified, and their percentage frequency in the NPLC determined: endothelial cells (50%), macrophages (23%), desmin-positive cells (14%), immunocompetent cells (10%, including T-, B-cells, pit and large vacuolated cells-both immunopositive to the asialo-GM 1 antigen) and unidentified cells (3%). These results show that, apart from the more familiar varieties of NPLC, two groups of cells exist in the liver which have not yet been fully identified and in which the immunocompetent cells predominate numerically.

Animals↗
PubMed1989

Protective properties of a human IgG preparation rich in antibodies to a wide spectrum of lipopolysaccharides.

Naturally occurring human IgG, rich in antibodies to different lipopolysaccharides was investigated for possible protective effects against lethal endotoxin shock and lethal gram-negative infection in mice. The IgG preparation was obtained from pooled serum of selected blood donors with high concentrations of antibodies to 11 different LPS as measured by ELISA. The human IgG (5 mg/mouse) protected C3H/TifF mice against an otherwise lethal infection with Salmonella typhimurium. The human IgG also inhibited the lethality induced by purified LPS in D-galactosamine sensitized C57B1/6 mice. The protection was dependent on the IgG dose given. However, protection was not obtained against all the LPS preparations tested. Absorption of the IgG with different LPS, showed the protection to be caused by serotype-specific anti-LPS antibodies. Protection against a given LPS was not related directly to the corresponding anti-LPS titer as measured by ELISA and passive hemolysis. The interpretation of these results is discussed.

Animals↗
PubMed1989

Fatty acid alterations and polymyxin B binding by lipopolysaccharides from Pseudomonas aeruginosa adapted to polymyxin B resistance.

Lipopolysaccharides were extracted from freeze-dried cells of Pseudomonas aeruginosa PAO1 (polymyxin B susceptible), isolate A (polymyxin B resistant), and isolate A-reverted (polymyxin B intermediate resistance) by either the phenol-chloroform-petroleum ether or the modified phenol-water method. Isolate A and isolate A-reverted had drastic losses of 2-hydroxydodecanoic acid and significant decreases in 3-hydroxydecanoic acid. Concentrations of amide-linked 3-hydroxydecanoic acid were similar in all three strains. Minor alterations were noted in the composition of 3-deoxy-D-manno-2-octulosonic acid, heptose, phosphate, neutral sugars, and amino compounds. The concentrations of rhamnose in isolate A and of rhamnose and glucose in isolate A-reverted were significantly different from those in PAO1. Trace amounts of mannose and other minor unidentified carbohydrates were detected in all strains. Polymyxin B included in isolate. A growth medium complexed with lipopolysaccharides and remained bound throughout purification. PAO1 lipopolysaccharides bound more polymyxin B than did isolate A lipopolysaccharides. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis indicated minor differences in smooth- and rough-form lipopolysaccharides of the different strains. We propose that loss of hydroxy fatty acids from lipopolysaccharides perturbs outer membrane hydrophobicity and is a contributing factor to polymyxin B adaptive resistance.

Drug Resistance, Microbial↗
PubMed1989

The role of intestinal endotoxin in experimental peritonitis.

Escape of endotoxin from the intraintestinal site was investigated in experimental models of intestinal ischemia and during intraabdominal infection in rats. Following the instillation of Salmonella abortus equi endotoxin (S-form) into the proximal large bowel, we recorded the presence of the lipopolysaccharide molecule in the bowel wall, the intestinal lymph nodes, the peritoneal cavity, and in the liver sinusoids by immunohistochemical methods. At 3, 6, 12, 24, and 48 hr after the operative procedure, peritoneal fluid, blood, and tissue samples were taken. Survival rates were similar between the two test-groups (occlusion of the superior mesenteric artery [SMA] and cecal ligation and puncture [CLP]) and were not influenced by the amount of the injected endotoxin. There was no detectable morbidity in the sham-operated control animals with endotoxin doses up to 20 mg. Endotoxin could only be detected at 24 and 48 hr in the SMA group in the liver as well as in the peritoneal sediment and in intestinal lymph nodes. CLP and control samples remained negative throughout the observation period. Bacteria were found intraperitoneally within 12 to 24 hr in the SMA group and within 3 to 12 hr in the CLP group.

Animals↗
PubMed1988

Are antimitochondrial antibodies in primary biliary cirrhosis induced by R(rough)-mutants of enterobacteriaceae?

Antimitochondrial antibody (AMA)-positive serum samples from 45 patients with primary biliary cirrhosis (PBC) and AMA-negative serum samples from patients with chronic liver diseases, systemic lupus erythematosus, or rheumatoid arthritis were studied by an immunoblot technique with mitochondria from bovine heart and pig kidney and with several strains of gram-negative bacteria as antigens after separation by sodiumdodecylsulphate polyacrylamide gel electrophoresis. Serum from patients with PBC recognised up to three mitochondrial antigens with molecular weights of 70 kD, 50 kD, and 42 kD. Equivalent patterns were found with bands at 70-80 kD and 50-52 kD with Enterobacteriaceae as antigens. AMA-reactive polypeptides were localised in the ribosomal and membrane fractions from Enterobacteriaceae but differed from known outer membrane proteins. Conversely, PBC-specific mitochondrial antigens at 70 kD and 50 kD were recognised by rabbit antisera against Salmonella minnesota Rb and Rc mutants but not by antisera against wild-type Enterobacteriaceae. Absorption experiments and two-dimensional immunoblotting studies confirmed that mitochondria and gram-negative bacteria share identical PBC-specific determinants. It seems that PBC-specific antigens are expressed in gram-negative bacteria and that these antigens may be immunogenic in mutants with defective polysaccharide synthesis. The data support the hypothesis of a bacterial aetiology for PBC.

Adult↗
PubMed1988

Analysis of Salmonella lipopolysaccharides by sodium deoxycholate-polyacrylamide gel electrophoresis.

Lipopolysaccharides (LPSs) were analyzed by polyacrylamide gel electrophoresis (PAGE) in the presence of sodium deoxycholate (DOC) or sodium dodecyl sulphate (SDS) and the results obtained compared. Two-dimensional PAGE of the S form of LPS revealed that, with SDS, bands which appeared to be single after the one-dimensional experiment were resolved into several bands after two-dimensional electrophoresis. In the presence of DOC, however, a diagonal of single bands was obtained in one-dimensional electrophoresis indicating optimum resolution. The high quality of resolution by DOC-PAGE was constant for amounts of LPS up to 20 micrograms. Finally, DOC-PAGE does not require boiling of the samples in DOC, which may be an advantage over SDS-PAGE.

Deoxycholic Acid↗
PubMed1988

Large-scale fractionation of S-form lipopolysaccharide from Salmonella abortus equi. Chemical and serological characterization of the fractions.

The S-form lipopolysaccharide of Salmonella abortus equi was separated by a newly elaborated extraction method with organic solvents into three fractions of different chain length of the O-polysaccharide they contained. The three fractions were designated long-chain (20-50 repeating units), short-chain (0-6) and R-fraction (no repeating units) according to their migration pattern in polyacrylamide gel electrophoresis in the presence of sodium dodecylsulphate. The nature of the fractions as long- and short-chain and as R-fraction was confirmed by chemical analysis. The concentration of O-specific sugars was highest in the long-chain fraction, where their molar ratio to glucosamine was ca. 25:1. In the short-chain fraction the ratio of O-sugars to glucosamine was 2.5:1, and in the R-fraction O-specific sugars were absent. The serological properties of the three fractions were in good agreement with their chemical composition.

Carbohydrates↗
PubMed1988

Immune carrier properties of acid-treated Salmonella minnesota R595 bacteria. The immune response to TNP-bacterial conjugates in rabbits and mice.

Salmonella minnesota R595 bacteria from which the core region of the lipopolysaccharide on the cell wall had previously been removed by mild acid treatment were trinitrophenylated. Differing amounts of these trinitrophenyl naked bacterial conjugates (TNP-NB), covering a range of epitope densities, were used for immunising mice and rabbits via the intraperitoneal or intravenous routes without adjuvants. It was found that such acid-treated, naked bacteria were effective carriers for the covalently linked hapten, TNP, with an optimum epitope density of 15 micrograms TNP/mg NB. Significant immune responses were obtained with dose levels as low as 50 ng TNP. The possible applications of acid-treated, naked bacteria as universal carriers having inherent adjuvant activity are discussed.

Acetates↗
PubMed1988

Evaluation of procoagulant activity production and other coagulative functions in cancer patients receiving acid treated Salmonella minnesota R 595 (Re).

Blood clotting parameters were measured in six patients with gynecologic tumors following i.v. administration of acetic acid-treated Salmonella minnesota R595 (Re), which has been previously demonstrated to enhance impaired immune functions in the same patients. Although these bacteria possess a more exposed lipid A at their surface which has the potential to stimulate the coagulative cascade, no evidence of plasma hypercoagulative state was detected. In fact, procoagulant activity generated by patients' mononuclear cells after Salmonella treatment was not significantly higher than that produced by patients' cells before treatment. Moreover, other haemostatic laboratory parameters were unaffected by in vivo treatment with bacteria.

Acetates↗
PubMed1988

Induction of tolerance to lipopolysaccharide (LPS)-D-galactosamine lethality by pretreatment with LPS is mediated by macrophages.

In mice treated with D-galactosamine, lipopolysaccharide (LPS) exhibits enhanced toxicity (C. Galanos, M. A. Freudenberg, and W. Reutter, Proc. Natl. Acad. Sci. USA 76:5939-5943, 1979). Pretreatment of mice with LPS before D-galactosamine rendered them tolerant to the enhanced lethal effect of LPS. Tolerance was established at 1 h after LPS injection and, depending on the dose of LPS used for pretreatment, lasted for up to 48 h. With C3H/HeJ mice with acquired sensitivity to LPS (M. A. Freudenberg, D. Keppler, and C. Galanos, Infect. Immun. 51:891-895, 1986), i.e., mice that had been administered C3H/HeN macrophages, pretreatment with LPS induced tolerance only if the C3H/HeN macrophages were already present at the time of pretreatment. This indicates that, like lethality, induction of tolerance by LPS is a macrophage-mediated phenomenon. Direct interaction of LPS with macrophages is the first step in the initiation of tolerance or toxicity. C3H/HeN macrophages (2 X 10(7], incubated with minute amounts of LPS (0.5 to 0.02 microgram) in vitro and transferred subsequently to C3H/HeJ mice, induced lethality when administered together with or after D-galactosamine and tolerance when injected before D-galactosamine. Macrophages activated in vitro lost their tolerance- and lethality-inducing properties upon further incubation in LPS-free culture medium for 18 h. Such macrophages could be successfully restimulated by a new addition of LPS.

Animals↗
PubMed1988

Longitudinal study of antibody response to lipopolysaccharides during chronic Pseudomonas aeruginosa lung infection in cystic fibrosis.

Antibodies to Pseudomonas aeruginosa from 10 cystic fibrosis patients with chronic P. aeruginosa lung infections were quantitatively and qualitatively analyzed. The development of specific antibodies in patient serum was evaluated in a longitudinal study (1972 to 1987). The concentrations and specificities of immunoglobulin G (IgG) and IgM antibodies to purified lipopolysaccharides (LPS) from clinical isolates of P. aeruginosa and to a variety of other gram-negative bacteria were studied by immunoblotting and enzyme-linked immunosorbent assay techniques. Results were compared with the number of immunoprecipitates to P. aeruginosa whole-cell extracts detected by crossed immunoelectrophoresis. IgG, but not IgM, anti-Pseudomonas LPS concentrations increased significantly at the onset of chronic infection and continued to increase during the course of the infection. There was a good positive correlation between the concentration of IgG anti-Pseudomonas LPS antibodies and the number of crossed-immunoelectrophoresis precipitins. The increases in IgG anti-LPS antibody concentrations were much higher to Pseudomonas LPS than to other LPSs. Binding studies demonstrated an increase in binding of IgG anti-Pseudomonas LPS during infection, whereas the binding of other anti-LPS antibodies decreased. Immunoblotting studies confirmed that antibodies reacted strongly with Pseudomonas LPS and weakly with Escherichia coli core-lipid A. The specificity of the reaction with Pseudomonas LPS increased with the duration of infection. It is concluded that anti-LPS response in cystic fibrosis patients during chronic P. aeruginosa infection demonstrates a marked increase in IgG anti-Pseudomonas LPS antibody concentration, specificity, and affinity. The anti-LPS enzyme-linked immunosorbent assay is proposed as a routine test to diagnose and to follow the course of chronic P. aeruginosa lung infection in patients with cystic fibrosis.

Adolescent↗
PubMed1988

Comparative immunochemistry of lipopolysaccharides from typable and polyagglutinable Pseudomonas aeruginosa strains isolated from patients with cystic fibrosis.

Lipopolysaccharide (LPS) was extracted and purified from three Pseudomonas aeruginosa strains isolated from the infected lungs of patients with cystic fibrosis. Two of the strains could be typed by O-specific antibody (O:3 and O:9), and the third was polyagglutinable (O:3/9). The separated LPS was characterized by chemical and serological methods. The main neutral sugar constituents (glucose, rhamnose, and heptose) were found in various proportions in the three strains, whereas the amounts of glucosamine, galactosamine, ketodeoxyoctonate, and phosphate were more constant. Ester-bound C12, C16, 3-OH-C10, and 2-OH-C12, together with amide-bound 3-OH-C12, fatty acids were present in equimolar proportions in all three strains. Considerable amounts of LPS were liberated in the culture supernatant of the O:3 bacteria but not in those from the other two strains. This free LPS was shown to be immunologically identical to the cell-bound LPS and the extracted LPS. By sodium dodecyl sulfate-polyacrylamide gel electrophoresis, O:3 and O:9 LPS showed a ladder pattern characteristic of smooth LPS, while O:3/9 LPS appeared rough. Rabbit antisera used for O-typing were found by enzyme-linked immunosorbent assay to contain anti-LPS antibodies that reacted strongly with homologous LPS, moderately with O:3/9 LPS, and slightly with heterologous LPS. Immunoblotting showed that common antigenic determinants in the core-lipid A part were involved in the observed cross-reaction. The polyagglutinability of P. aeruginosa may be explained by the antibodies to these common determinants that arose from the partial absence of O polysaccharides.

Antigens, Bacterial↗
PubMed1988

The significance of high-density lipoproteins (HDL) in the clearance of intravenously administered bacterial lipopolysaccharides (LPS) in mice.

The direct immunofluorescence technique was used to study the presence of high-density lipoproteins (HDL) in the liver, spleen and kidney of mice before and after intravenous administration of purified lipopolysaccharides (LPS) from Escherichia coli O 75, Salmonella abortus equi and Salmonella minnesota R 595, as well as free lipid A. Untreated mice had small granules of HDL in the hepatocellular cytoplasm, which appeared more pronounced after oral administration of fat. After intravenous administration of LPS, hepatocellular HDL decreased continuously and was no longer visible 1 hour after injection of LPS or lipid A. Five to ten minutes after administration, smooth-form LPS were located in sinusoidal cells, and rough form LPS and lipid A were found in both parenchymal and nonparenchymal liver cells. All toxins were demonstrated in both cell populations 1-4 hours after injection. The spleen was free of HDL, while there was a strong uptake of LPS into the cells of the reticulo-endothelial system. The kidney of experimental mice had small HDL granules in the epithelial cells of the proximal tubules, with a tendency to move to the lumen 1 hour after LPS injection, while there was a transient granular deposition of LPS in the glomeruli. The results suggest that the early uptake of circulating LPS by cells of the reticulo-histiocytic system in liver and spleen, as well as by hepatocytes, is not mediated by HDL. However, HDL located in hepatocytes or present in the circulation of experimental mice seem to be eliminated through the bile and the urine, induced by LPS.

Animals↗
PubMed1988

Alterations in the chemical composition and antigenicity of Escherichia coli O89 lipopolysaccharide and lipid A after 60Co gamma irradiation.

The chemical composition and the antigenicity of Escherichia coli lipopolysaccharide (LPS) and lipid A were investigated after irradiation with 150 kGy 60Co-gamma ray. Compared to the original preparations, the irradiated LPS showed a significant reduction in glucosamine, glucose and galactose and a decrease in the phosphate content. The fatty acid components were reduced to a smaller degree. Irradiation induced a reduction in the antigenicity of the polysaccharide part. The amount of glucosamine and phosphate decreased in the irradiated lipid A. The fatty acid content was significantly reduced. The alteration in the chemical composition was not paralleled by changes in the antigenicity of irradiated lipid A.

Antigens, Bacterial↗
PubMed1988

Hypersensitivity to endotoxin and mechanisms of host-response.

It was shown here that the lethal activity of endotoxin may be considerably enhanced in experimental animals treated with different agents. Some of these agents represent killed bacteria, bacterial products or hepatotoxic agents and their sensitizing effects may be relevant to the sensitization seen during gram-negative infections. This study provided direct evidence that macrophages are cells mediating the lethal activity of endotoxin and that the direct interaction of LPS with macrophages is the first step in its initiation. Further, TNF is a macrophage mediator responsible for the induction of lethality. In normal animals as well as in the various sensitization models investigated, TNF alone was sufficient to induce lethality. Therefore, the stimulation of macrophages by LPS to produce TNF is a mechanism common to diverse lethality models. It would seem therefore that the complexity of endotoxicity in gram-negative infections is related primarily to the complexicity of the factors altering the susceptibility of the host rather than to be actual mechanisms of the lethal action of endotoxin. The identification of the factors leading to sensitization and their underlying mechanisms would contribute to a better understanding of the complex phenomenon endotoxicity.

Acetylmuramyl-Alanyl-Isoglutamine↗
PubMed1987

Endotoxic properties of synthetic pentaacyl lipid A precursor Ib and a structural isomer.

A pentaacyl precursor of lipid A biosynthesis, termed precursor Ib, and a structural isomer have been chemically synthesized. These compounds were, in comparison to synthetic Escherichia-coli type lipid A or lipopolysaccharide, analyzed for their activity in typical endotoxin test systems. It was found that both precursor Ib and the isomer exhibited similar or only slightly lower pyrogenic, lethal and Shwartzman-phenomenon-inducing activity than lipid A. All preparations were comparable in their B-lymphocyte mitogenicity, macrophage-activating capacity and immunoreactivity towards lipid A antisera. The proton nuclear magnetic resonance spectra of the 1-dephospho derivative of synthetic and bacterial precursor Ib were indistinguishable proving that the previously proposed structure for precursor Ib is correct.

Animals↗