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C Galanos

Publications and source records attributed to C Galanos.

At least 145 records · Page 8Linked to original sources
PubMed1983

Granulocyte activation by endotoxin. I. Correlation between adherence and other granulocyte functions, and role of endotoxin structure on biologic activity.

Reminiscent of high concentrations of formylated chemotactic peptides, another group of bacteria-derived products, the lipopolysaccharides and lipid A, stimulate PMN adherence to petri dishes. Attachment and spreading of PMN is accompanied by intense release of secondary granule constituents and marked stimulation of the hexose monophosphate shunt activity. Dose-response studies with endotoxin preparations of diverse activity show that induction of PMN adherence, enzyme release, and respiratory burst activation are highly correlated, suggesting that this functional triad is mediated by a common mechanism. Hyperadhesiveness inducing concentrations of the chemotactically inert endotoxin lead to marked inhibition of PMN migration without affecting the direction-finding mechanism of the cell toward formylated peptides and C-derived chemotaxin(s). Endotoxin preparations at a lower grade of aggregation are more active, and the polysaccharide chains of the molecule are not essential with respect to PMN stimulation. Under our experimental conditions, endotoxin-induced stimulation of PMN is not inhibited by indomethacin, suggesting independence of cyclooxygenase-derived products. This type of PMN activation may play an important role in endotoxin-mediated tissue damage in vivo. Furthermore, hyperadhesion-induced inhibition of PMN migration to inflammatory sites during endotoxemia might hamper host resistance.

Arachidonic Acids↗
PubMed1982

Isolation, purification, and chemical analysis of the lipopolysaccharide and lipid A of Acinetobacter calcoaceticus NCTC 10305.

The lipopolysaccharide of Acinetobacter calcoaceticus NCTC 10305 (London) was obtained by a modified phenol/chloroform/light petroleum method from the bacterial cells and from the culture medium in yields of 1.6% and 2.2% respectively (based on the bacterial dry weight). On chemical analysis, both preparations proved to be identical. The lipopolysaccharide obtained from the cells was purified by repeated ultracentrifugation, electrodialysis, and precipitation with sodium chloride. It was free of nucleic acids, proteins, and glycans. In the analytical ultracentrifuge, the triethylamine and sodium salt forms of the lipopolysaccharide showed a s20 value of 8.9 S and 51 S, respectively. The lipopolysaccharide consisted of glucosamine, 3-deoxy-D-manno-octulosonic acid, D-glucose, fatty acids, and phosphate in a molar ratio of 2:1:7:6:4. The fatty acids were predominantly lauric acid, 2-hydroxy, and 3-hydroxylauric acid in a molar ratio of 1:1:2. Only 3-hydroxylauric acid was found in amide linkage. On mild acid hydrolysis of the lipopolysaccharide, 65% lipid A were obtained, to which glucosamine was retained quantitatively. It still contained 50% of the original glucose, while one third (15%) of the liberated glucose was in monomeric form.

Acinetobacter↗
PubMed1982

Distribution and antigenic properties of the O-determinants of Salmonella zuerich (1, 9, 27 46).

Fractionation of the O-polysaccharide derived from Salmonella zuerich (1, 9, 27, 46) on a concanavalin A polymer permitted immunological and chemical analysis on the different fractions. The S. zuerich O-polysaccharide preparation is composed of two distinct populations of molecules: one, ZB1-, devoid of O-antigenic determinant 1, and the other, ZB1+, carrying the determinant 1. This determinant is linked to the presence of D-glucosyl residues on the side chain. O-polysaccharide molecules 1-, devoid of D-glucose, are shown to carry simultaneously both determinants 27 and 46. These determinants are not evenly distributed on the molecules. The expression of determinants 46 (-[Tyv]-betaMan-, where Tyv = tyvelose) seems to be restricted to a distinct specific configuration, and it is altered by the presence of either determinant 27 (-[Tyv]-alphaMan-) or determinant 1 (Glc-Gal-) in the close neighbourhood. Molecules 1+ are partially or completely substituted by glucosyl residues and react with anti-1 antibodies. They are characterized by the same uneven distribution of determinants 27 and 46 as molecules ZB1-. In conclusion, the O-polysaccharide chains are heterogeneous. They contain simultaneously factors 27, 46, and often also 1.

Antibodies, Bacterial↗
PubMed1982

Time course of cellular distribution of endotoxin in liver, lungs and kidneys of rats.

The time course of distribution of 2 endotoxic lipopolysaccharides (LPS), S. abortus equi (S form) and S. minnesota R 595 (R form, Re), in liver, lungs and kidneys was studied by the immunoperoxidase method in rats. After its uptake in the liver, both LPS were first detectable in Kupffer cells and granulocytes, the R form also in hepatocytes. A redistribution of the S-form LPS from Kupffer cells to hepatocytes was observed on Day 3 after injection. The detectability of both LPS was lost between Days 5 and 9 after injection. In the lungs both LPS were detectable later than in the liver. Here the LPS were also found in alveolar and bronchiolar macrophages, which shows that they can also be eliminated through this organ. The kidneys remained essentially free of LPS, small amounts being detectable here only in the first 24 h.

Animals↗
PubMed1982

Effect of ionizing radiation on chemical and biological properties of Salmonella minnesota R595 lipopolysaccharide.

Lipopolysaccharide of the Salmonella minnesota Re mutant R595 was irradiated with 60Co gamma doses of 50, 100, 150 and 200 kGy. The irradiated preparations were less toxic, less active in the Shwartzman reaction and as activators of the complement system, but they had retained the protection activity against the lethal action of endotoxin. The irradiation resulted in a dose-dependent decrease in the amounts of constituents (glucosamine, KDO, fatty acids) of the original lipopolysaccharide. With increasing irradiation doses increasing amounts of the irradiated material became dialysable (up to 21% in the 200 kGy sample). Only 50% of total fatty acids were present in the 200 kGy preparation compared to the parent lipopolysaccharide. The degradation products formed during irradiation have not been identified.

Animals↗
PubMed1981

[Endotoxin effect on intravascular volume and kidney function in an acute experiment in the rat].

The effect of intravenous endotoxin (Sal. abortus equi) in a semilethal dose in rats was very individual. Animals showing a drop in creatinine clearance were termed sensitive (E II), and animals without effect on the creatinine clearance non sensitive (E I). In the sensitive animals a reduction of intravascular space by albumin loss into the extravascular space, a decrease of renal blood flow and an average fall in creatinine clearance of 40% were found. The non sensitive animals (E I), on the other hand, showed no significant change in albumin space but, in contrast to E II, their hematocrit fell, a fact interpreted as vasodilatation and inflow of fluid. In these animals (E I) no change in creatinine clearance was measured. Orthograde tubular perfusion of endotoxin through the loop of Henle elicited no tubular glomerular feedback response. In these sensitive animals (E II), the absence of tubular glomerular feedback vasoconstriction, hypovolemia and a fall in blood pressure suggest a prerenal cause for this type of acute renal failure. Additional factors responsible for acute renal failure are discussed.

Animals↗
PubMed1981

Lipid A component of lipopolysaccharides from Coxiella burnetii.

Free lipid A from phase I and phase II Coxiella burnetii lipopolysaccharides was isolated and studied serologically. Antisera against lipid A from phase I and phase II C. burnetii cross-reacted with the lipid A preparations from both phases as well as with Salmonella lipid A.

Animals↗
PubMed1980

Isolation and partial chemical characterization of the IgG Fc receptor of human T lymphocytes and production of an antiserum.

We report here the isolation of an IgG Fc receptor from normal human T lymphocytes. The purified receptor has a nonreduced and a reduced component of molecular weights 120,000 and 60,000, respectively, and it was functionally active in the in vitro blocking of rosette formation between T lymphocytes and IgG-coated ox erythrocytes. An antiserum raised to the Fc receptor and an isolated F(ab')2 fragment of this antiserum, also blocked rosette formation between T cells and IgG-coated ox erythrocytes. In contrast, rosette formation between T lymphocytes and IgM-coated ox or sheep erythrocytes was not blocked by the F(ab')2 fragment, demonstrating the marked specificity of this antiserum for the IgG Fc receptor. In addition, this antiserum did not block the Fc receptors of non-T cells, indicating that the T-cell IgG Fc receptor has unique antigenic determinants not shared with B cells.

Electrophoresis, Polyacrylamide Gel↗
PubMed1980

Interaction of lipopolysaccharides with plasma high-density lipoprotein in rats.

The method of crossed immunoelectrophoresis was used to investigate early changes in plasma proteins of rats treated with lipopolysaccharide (LPS). Intravenous injection of a smooth (S)- and a rough (R)-form preparation led to alterations in the high-density lipoprotein (HDL) precipitation peak. The changes were dose dependent and characteristic for each LPS. The changes were identified as being due to the formation of a complex of LPS with HDL, the complex of the S-form LPS with HDL migrating slower and that of the R-form LPS with HDL migrating faster than free HDL. The fate of the complex was followed in the plasma of injected rats, and it was shown that the R-form LPS complex disappeared after several hours, whereas the S-form LPS complex was still partly present after 2 days. Plasma clearance studies, carried out with 14C-labeled LPS, revealed similar differences in the rate of elimination of the two LPSs. In both cases the time of clearance resembled that of the disappearance of LPS-HDL complex. These results may indicate that HDL represents a transport protein for LPS in plasma to organs of clearance or to other cellular targets.

Animals↗
PubMed1979

Galactosamine-induced sensitization to the lethal effects of endotoxin.

Treatment of rabbits, rats, and mice with D-galactosamine increased their sensitivity to the lethal effects of lipopolysaccharide several thousand fold. The susceptibility of the animals was highest when the lipopolysaccharide was injected together with galactosamine and decreased successively when injection was carried out 1, 2, and 3 hr later. Sensitization was absent when the lipopolysaccharide was administered 1 hr before or 4 hr after galactosamine. The onset of lethality after treatment with galactosamine and lipopolysaccharide occurred faster than with lipopolysaccharide alone; usually all animals died 5-9 hr later. The galactosamine-induced sensitization to lipopolysaccharide could be reversed by uridine which is known to inhibit the early biochemical alterations induced by the amino sugar in the hepatocytes. Although galactosamine is known to exhibit hepatotoxic activity inducing ultimate necrosis of the hepatocytes, the data so far suggests that the sensitization to lipopolysaccharide is related only to the early metabolic effects of the hexosamine.

Animals↗
PubMed1979

A lipopolysaccharide-binding cell-surface protein from Salmonella minnesota. Isolation, partial characterization and occurrence in different Enterobacteriaceae.

1. Protein extracts obtained from Salmonella minnesota Re mutant cells by treatment with EDTA/NaC1 solution contain a protein which exhibits high affinity to bacterial lipopolysaccharides. The isolation and partial characterization of this lipopolysaccharide-binding protein is described. 2. The protein was purified from EDTA extracts by a two-step procedure consisting of ion-exchange chromatography on CM-Sephadex and preparative polyacrylamide gel electrophoresis at pH 9.5. The yield of the total purification procedure was around 16%. 3. The resulting protein preparation was homogeneous on the basis of disc gel electrophoresis, dodecylsulfate gel electrophoresis, isoelectric focusing in polyacrylamide gel and immunoelectrophoresis. 4. The isoelectric point of the protein was found to be 10.3 at 4 degrees C. Its molecular weight determined by dodecylsulfate gel electrophoresis is 15000. Its amino acid composition is characterized by the absence of histidine and proline, a low content in tyrosine and high amounts of alanine, lysine, aspartic and glutamic acid residues, or their respective amides. 5. The lipopolysaccharide-protein association was shown to be mainly due to ionic interactions of the basic protein with negatively charged groups (probably phosphate and pyrophosphate groups) of the lipid A moiety. 6. Purified lipopolysaccharide-binding protein is immunogenic in rabbits, thus enabling the preparation of specific antiserum. 7. The protein is located at the surface of Salmonella minnesota Re mutant cells as revealed by antiserum absorption with total bacteria. Ferritin-labelling studies further demonstrated that it is evenly spread over the entire cell surface. 8. Comparative antiserum absorption studies using smooth and rough strains of Salmonella minnesota, Salmonella typhimurium, Escherichia coli, Klebsiella and Shigella revealed the presence of lipopolysaccharide-binding protein (or a serologically cross-reacting antigen) in most of the strains tested. From these results the protein can be considered as a common antigen of Enterobacteriaceae.

Amino Acids↗
PubMed1979

Attachment to erythrocytes of uniform salt forms of lipopolysaccharides from Salmonella abortus-equi and its inhibition by various animal sera.

Lipopolysaccharides (LPS) readily attach to erythrocyte membranes in vitro, resulting in hemagglutination in the presence of the homologous bacterial antibodies. The attachment of LPS to red blood cells can be prevented by certain, but not all, animal sera. In this study, the attachment of uniform salt forms of LPS from Salmonella abortus-equi to erythrocytes from various animal species was investigated. The uniform salt preparations were significantly more active than the starting material. Similar findings were obtained with erythrocytes from man, sheep, rabbit, and guinea pig. These results were not due to differences in antibody neutralizing capacity, since all preparations showed essentially identical activity. When sera from various animal species were used as inhibitors of LPS attachment, inhibition of erythrocyte modification by equivalent, but not by identical, amounts of LPS was essentially the same.

Animals↗
PubMed1979

Macrophage factor controlling differentiation of B cells.

Peritoneal macrophages of the mouse produce, in response to cell wall components of Gram-negative bacteria (lipopolysaccharide and lipoproteins), a factor that causes antigen-stimulated B cells of differentiate into antibody-producing cells. Unlike lipopolysaccharide, this factor is not mitogenic for B cells. Production of the macrophage factor does not depend on participation of T cells or other accessory cells since it is readily produced by several cloned macrophage cell lines as well as by peritoneal macrophages of athymic nude mice. The factor is active only in conjunction with antigen. T cells, although apparently not necessary, amplify its effect. The factor induces phenotypic differentiation of B cell precursors as selectively as thymopoietin induces differentiation of prothymocytes.

Animals↗
PubMed1979

Preparation and properties of a standardized lipopolysaccharide from salmonella abortus equi (Novo-Pyrexal).

The paper describes the preparation of the lipopolysaccharide from Salmonella abortus equi as obtained by standardized methods. The include the extraction with pehnol/water followed by phenol/chloroform/petroleum ether extraction, ultra-centrifugation, electrodialysis and conversion to the uniform sodium salt form. Chemical composition and physico chemical properties are described. The preparation, which is free from contaminants, was tested for local Shwartzman reactivity, pyrogenicity, lethal toxicity, mitogenicity, reactivity towards complement and tumoricidal action.

Animals↗