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Immunological investigation of infants with septicemia or meningitis due to group B Streptococcus.

Purified polysaccharide from type III group B Streptococcus contains both a type III-specific determinant and another determinant that is common to strains of serotypes other than type III. The polysaccharide contains sialic acid, galactose, heptose, glucose, glucosamine, and mannose. Serum antibody to this antigen was measured by means of a radioactive antigen-binding assay. Sera from 36 (67.9%) of 53 women with healthy newoborns contained antibody, a prevalence significantly different from that in sera from 15 women (13.3%) whose neonates developed septicemia or meningitis due to type III group B Streptococcus. Complete concordance for presence or absence of anticapsular antibody in sera from 14 women at delivery and in their neonates' cord sera was demonstrated; this concordance indicates transplacental transfer of antibody. Sera from each of four adults with invasive infection who were studied during convalescence contained antibody to the capsular polysaccharide of type III group B Streptococcus. In contrast, antibody was absent from 10 infants who had recovered from bacteremia, septicemia, and/or meningitis due to type III group B Streptococcus.

Antibodies, Bacterial↗

Lipopolysaccharide-derived serotype polysaccharides from Neisseria meningitidis group B.

Three immunologically distinct types of polysaccharides have been isolated by diethylaminoethyl (DEAE) chromatography from the lipopolysaccharide extracts of group B Neisseria meningitidis. All types contain a set of common determinants, as well as distinct ones; all of these determinants are detectable by either immunodiffusion or enzyme-linked immunosorbent assay (ELISA). The polysaccharides elute from a Sepharose 4B column in the range of 2-3 x 10(5) daltons and have isoelectric points from 4.2 to 4.3. Their antigenicity is destroyed by oxidation but is unaffected by neuraminidase, lysozyme, or trypsin. One type of polysaccharide cross-reacts with the Gc2 polysaccharide of Neisseria gonorrhoeae in immunodiffusion systems. Chemical analysis indicates that these polysaccharides contain hexoses, hexosamines, 2-keto-3-deoxyoctonate, ethanolamine, and heptose; analysis of amino acids indicates protein contents of less than 0.05%. In contrast to the lipopolysaccharide from which they are derived, these polysaccharides contain no lipid A and less than 0.5% fatty acids. All three types are precipitated by wheat germ agglutinin but not by concanavalin A or fucose-binding protein. Specific inhibition of this precipitation can be achieved with N-acetyl glucosamine. These antigens may be the bases of a lipopolysaccharide-derived typing system for group B N. meningitidis.

Animals↗

Isolation of a serogroup 1-specific antigen from Legionella pneumophila.

Outer membrane material was extracted from a serogroup 1 strain of Legionella pneumophila using ethylenediaminetetraacetate. Ferritin-conjugated antiserum reacted only at the surface of the organism, as seen by electron microscopy. Outer membrane material was fractionated into five peaks by molecular sieve chromatography using a gel that had been equilibrated in a buffer containing sodium deoxycholate. One resolved peak (approximately 4x10(4) daltons) was highly active serologically. When rechromatographed in the absence of sodium deoxycholate, material from this peak reaggregated to approximately 10(6) daltons. Ther serologic activity of this antigen was restricted to L. pneumophila serogroup 2, although minor cross-reactions with strains of serogroups 2 and 4 were detected using an enzyme-linked immunosorbent assay. The antigen was less than 10% carbohydrate, 15% protein, 1.1% phosphate, and the remainder lipid of unknown composition. Neither 2-keto-3-deoxyoctonate nor heptose was detected, and the antigen did not induce a Shwartzman reaction. Only one band was seen on sodium dodecyl sulfate-polyacrylamide gel electrophoresis.

Animals↗

Specificity and cross-reactivity of monoclonal antibodies reactive with the core and lipid A regions of bacterial lipopolysaccharide.

Twenty-nine murine monoclonal antibodies (MAbs) were prepared against antigenic determinants in the core and lipid A regions of Escherichia coli and Salmonella minnesota lipopolysaccharide (LPS). At least eight distinct MAb specificities were identified. Epitopes recognized by MAbs bearing these specificities were localized in the hexose, heptose, and 2-keto-3-deoxy-D-manno-octulosonic acid regions of the core oligosaccharide and on lipid A. Two groups of MAbs exhibited multispecificity for similar but distinct core- and lipid A-related epitopes. Some core-reactive MAbs cross-reacted with corresponding E. coli and Salmonella rough mutant chemotypes; others were specific for E. coli J5 LPS. Lipid A-specific MAbs reacted with free lipid A from diverse sources. Few MAbs reacted with smooth LPS. Antibody cross-reactivity was restricted by inter- and intraspecies differences in covalent core structure and by epitope concealment by overlying O-side chain and core sugars. The putative cross-reactive and antiendotoxic properties of MAbs specific for the core-lipid A complex may be limited by the inability of such MAbs to recognize determinants on "native" LPS.

Animals↗

Structural requirements of endotoxic glycolipid for antitumor and toxic activity.

Endotoxic glycolipids extracted from the polysaccharide heptose-less Re mutant of Salmonella typhimurium were hydrolyzed with alkaline and acid reagents. Treatment with hydroxylamine caused the liberation of all O-ester linked fatty acids and resulted in abrogation of the toxicity (lethality to chick embryos) and ability to regress tumors (line-10 tumors in strain 2 guinea pigs). Treatment with dilute sodium hydroxide caused partial removal of O-ester linked fatty acids without loss of these activities. Toxicity and tumor-regressive potency were retained after removal of 2-keto-3-deoxyoctonate (KDO) by exposing the glycolipids to sodium acetate solution at pH 4.5. The majority of the glycolipids of the endotoxic extracts were rendered non-toxic but retained antitumor activity when hydrolyzed with boiling 0.1 N hydrochloric acid, which split KDO and glycosidic phosphate from the glycolipid molecules. Non-toxic glycolipid fractions possessing antitumor activity were separated from the acid hydrolysate by means of preparative thin layer chromatography. It was concluded that glycosidic bound phosphate and at least a portion of the fatty acids of the lipid A moiety are essential for toxicity, but that this phosphate is not an essential structural feature for tumor-regression activity.

Animals↗

Bacteriophage-resistant mutants of Escherichia coli K12. Location of receptors within the lipopolysaccharide.

A series of mutants of Escherichia coli K12 resistant to lipopolysaccharide (LPS)-specific bacteriophages were isolated, and examined with regard to their general properties, phage typing, chemical analysis of their LPS, and genetic analysis. Fourteen classes of mutants were distinguished on the basis of phage typing and sensitivity to bile salts. Three of the mutant classes are sensitive to phages to which the parent is resistant. Mutants which are sensitive to bile salts generally lack heptose in their LPS, but two mutant classes are exceptions to this rule. Analyses of the sugars in the purified LPS of all mutant classes indicated that mutants were obtained which are blocked at most stages in core polysaccharide synthesis. On the basis of the chemical analysis, in conjunction with phage typing data and other known properties of the mutants, it is deduced which residue(s) is involved as a receptor for each of the phages used and which residues hinder these receptors. Some of the mutant classes do not seem to be changed in their LPS structure. Many of the mutations map in or near the rfa locus, but some are far removed from this region.

Bacteriophage Typing↗

Studies on the chemical composition of lipopolysaccharide from Neisseria meningitidis group B.

A lipopolysaccharide was isolated from Neisseria meningitidis group B by phenol/water extraction and purified by differential ultracentrifugation. This preparation exhibited endotoxic properties as shown by the limulus-lysate assay. Mild acid hydrolysis of the lipopolysaccharides yielded a lipid A fraction and a polysaccharide fraction. The lipid A fraction contained fatty acids, phosphorus and glucosamine. Analysis of the polysaccharide fraction revealed the presence of glucose, galactose, glucosamine, 2-keto-3-deoxyoctonic acid and phosphorus. There was no heptose.

Fatty Acids↗

Isolation of atypical lipopolysaccharides from purified cell walls of Pseudomonas cepacia.

Wall fragments were prepared from two strains of Pseudomonas cepacia and from P. aeruginosa, and their contents of readily extractable lipid, pronase-digestible protein and lipopolysaccharide were measured. Lipopolysaccharide extracted from P. cepacia, although biologically active, contained no detectable 2-keto-3-deoxyoctonic acid, but contained phosphate, rhamnose, glucose, heptose and hexosamine in concentrations comparable to those found in P. aeruginosa.

Cell Wall↗

Ultrastructure and chemical composition of lipopolysaccharide extracted from Leptospira interrogans serovar copenhageni.

Lipopolysaccharide (LPS) from Leptospira interrogans serovar copenhageni was prepared from the aqueous phase of a phenol/water extract. Electron microscopic examination of negatively stained LPS showed a mixture of ribbon-like, round and ring structures. Carbohydrate analysis of the preparations revealed pentoses, hexoses, heptoses, hexosamines, and a 2-keto-3-deoxyonic acid which was chromatographically different from authentic 2-keto-3-deoxyoctonic acid (KDO). The major fatty acids of the LPS were hydroxylauric, palmitic and oleic acids. Although the leptospiral LPS preparations did not contain KDO or hydroxymyristic acid, they were otherwise morphologically and chemically similar to the LPS of other Gram-negative bacteria.

Chemical Phenomena↗

Composition of the lipopolysaccharide from different capsular serotype strains of Haemophilus influenzae.

Lipopolysaccharide (LPS) from all six serotype strains of Haemophilus influenzae was similar in composition. The oligosaccharide, of each LPS, was composed of glucose, galactose, heptose and 2-keto-3-deoxyoctonic acid. The lipid A was composed of glucosamine, phosphate and the fatty acids 14:0 and 3-OH 14:0. Each LPS also contained ethanolamine and ethanolamine phosphate, and the oligosaccharides from two strains additionally contained small amounts of glucosamine. Although the LPS was similar in composition, different serotypes had quantitative differences, especially in the galactose content, which correlated with the antigenic specificity of their homologous antisera and with their mobility on SDS-polyacrylamide gel electrophoresis (SDS-PAGE). A survey by SDS-PAGE showed that LPS from strains of the serotypes a, c and d was characteristically of lower Mr than the LPS from most (80%) serotype b strains.

Electrophoresis, Polyacrylamide Gel↗

Serological properties and immunobiological activities of lipopolysaccharides from black-pigmented and related oral Bacteroides species.

Lipopolysaccharides (LPS) from five species of oral Bacteroides, B. gingivalis strains 381 and ATCC 33277, B. oralis ATCC 33269, B. loescheii ATCC 15930, B. intermedius ATCC 25611 and B. corporis ATCC 33547, were extracted from whole cells by the phenol/water procedure, and subsequently purified by treatment with nuclease and ultracentrifugation. The LPS were composed of hexoses, glucosamine, fatty acids and phosphorus. Heptose and 2-keto-3-deoxyoctonate were not detected. The LPS preparations from B. gingivalis strains 381 and ATCC 33277 presented very similar SDS-polyacrylamide gel electrophoresis patterns when stained with ammoniacal silver. They produced a fused precipitin band against an antiserum to B. gingivalis 381 LPS in immunodiffusion tests. Antisera raised against the LPS from B. loescheii and B. intermedius reacted with the LPS prepared from all the oral Bacteroides strains except those of B. gingivalis. All the LPS preparations were mitogenic for spleen cells of BALB/c (nu/nu) mice, but not for thymus cells from C3H/HeN mice. The LPS induced marked mitogenic responses and polyclonal B cell activation for spleen cells of not only C3H/HeN (LPS responder) mice, but also C3H/HeJ (LPS nonresponder) mice. The mitogenic responses were not suppressed significantly upon addition of polymyxin B to the reaction mixture. These LPS also enhanced interleukin-1 production by murine peritoneal macrophages and mouse cell line J744. 1 macrophages. Hydrolysis of B. gingivalis ATCC 33277 LPS in 1 m-HCl at 100 degrees C for 1 h yielded lipid and polysaccharide. The lipid portion was largely composed of fatty acids and glucosamine, and was mitogenic for spleen cells from C3H/HeJ as well as C3H/HeN mice, while the polysaccharide portion induced no significant mitogenic responses under similar experimental conditions.

Animals↗

O-antigenic lipopolysaccharides isolated from a marine Vibrio, bio-serogroup 1875, possessing an antigenic factor in common with O1 Vibrio cholerae.

The chemical and serological characteristics of lipopolysaccharides (LPS) isolated from Vibrio bio-serogroup 1875 were compared with those of O1 Vibrio cholerae LPS. Vibrio bio-serogroup 1875 LPS contained all the component sugars which were found in O1 V. cholerae LPS, i.e. glucose, L-glycero-D-manno-heptose, fructose, glucosamine, perosamine and quinovosamine, though the amount of perosamine, a characteristic component of O1 V. cholerae LPS, was very low compared with that of O1 V. cholerae LPS. Their LPS additionally contained mannose and two unidentified neutral sugars which are not regular constituents of O1 V. cholerae LPS. Definite serological cross-reactivity in the passive haemolysis test between LPS from Vibrio bio-serogroup 1875 and LPS from O1 V. cholerae was demonstrated.

Antigens, Bacterial↗

Relationship between structure and antigenicity of O1 Vibrio cholerae lipopolysaccharides.

The relationship between the release of fructose from O1 Vibrio cholerae lipopolysaccharides (LPS) by dilute acetic acid hydrolysis and the decrease in their antigenicity was examined. Decrease in the antigenicity of LPS was not parallel with the release of fructose, and occurred very much later than the latter. Periodate oxidation of LPS resulted in the total elimination of the fructose and glucose, and two-thirds of the heptose constituents, but no difference in the antigenicity of LPS was observed before and after oxidation. These findings indicate that the fructose present in O1 V. cholerae LPS is not substantially involved in their specific antigenicity. In the O1 V. cholerae LPS, the fructose is in the branch structure, most probably in the core region.

Acetates↗

Biochemical and immunological comparison of lipopolysaccharides from Bordetella species.

Lipopolysaccharides (LPS) isolated from Bordetella pertussis, B. parapertussis and B. bronchiseptica were analysed for their chemical composition, molecular heterogeneity and immunological properties. All the LPS preparations contained heptose, 3-deoxy-D-manno-2-octulosonic acid, glucosamine, uronic acid, phosphate and fatty acids. The fatty acids C14:0, C16:0 and beta OHC14:0 were common to all the LPS preparations. LPS from B. pertussis strains additionally contained isoC16:0, those from B. parapertussis contained isoC14:0 and isoC16:0, and those from B. bronchiseptica contained C16:1. By SDS-PAGE, LPS from B. pertussis had two bands of low molecular mass, and the LPS from B. parapertussis and B. bronchiseptica showed low molecular mass bands together with a ladder arrangement of high molecular mass bands. Immunodiffusion, quantitative agglutination and ELISA demonstrated that the LPS from B. pertussis strains reacted with antisera prepared against whole cells of B. pertussis and B. bronchiseptica; LPS from B. parapertussis reacted with antisera to B. parapertussis and B. bronchiseptica, and LPS from B. bronchiseptica reacted with anti-whole cell serum raised against any of the three species. From these results, it is concluded that LPS from B. bronchiseptica has structures in common with LPS from B. pertussis and B. parapertussis, while the LPS from B. pertussis and B. parapertussis are serologically entirely different from each other.

Agglutination↗

Chemical characterization of lipopolysaccharides from Legionella feeleii, Legionella hackeliae and Legionella jordanis.

Lipopolysaccharides (LPS) from Legionella feeleii serogroup 1, L. hackeliae serogroup 1 and L. jordanis were subjected to chemical analysis. All three LPS contained D-mannose, D-glucose, D-glucosamine, L-glycero-D-manno-heptose, 2-keto-3-deoxyoctonic acid and glycerol. In addition the LPS of L. feeleii was characterized by L-quinovose (tentatively identified) and L-fucosamine, L. hackeliae LPS by D-quinovosamine, D-galactosamine and D-galacturonic acid, and L. jordanis LPS by D-quinovosamine. Phosphorylated sugars were detected in all three LPS. The backbone sugar of the lipid A part was in each case 2,3-diamino-2,3-dideoxy-D-glucose substituted with a complex pattern of fatty acid, including 20-22 different amide-linked (non-branched and methyl-branched) 3-hydroxy fatty acids of chain-length ranging from 12 to 23 carbon atoms. The fatty acid patterns included also ester-linked nonhydroxylated entities and the uncommon 27-oxo-octacosanoic acid and 29-oxotriacontanoic acid. The LPS of L. hackeliae and L. jordanis also contained heptacosane-1,27-dioic and nonacosane-1,29-dioic acid, and their 2-hydroxy analogues were characteristic of L. jordanis LPS. SDS-PAGE patterns of the three LPS were distinctly different. Both L. feeleii and L. jordanis produced smooth-form LPS with characteristic ladder patterns, whereas L. hackeliae LPS were of more rough-type character.

Carbohydrates↗

Epitopes of Bordetella pertussis lipopolysaccharides as potential markers for typing of isolates with monoclonal antibodies.

Three hybridomas (P1P3, D7 and 60.5) producing monoclonal antibodies (mAbs) against Bordetella pertussis lipopolysaccharide (LPS) were established. All reacted with the LPS from a typical, vaccine strain of B. pertussis (1414), but not with that of a variant strain (A100). Two of these mAbs (P1P3 and 60.5) cross-reacted with a B. bronchiseptica LPS; only one (P1P3) reacted with a B. parapertussis LPS. ELISA reactivities with intact LPSs, and defined partial structures covalently linked to bovine serum albumin, were compared. mAb 60.5 bound to the terminal region of a distal trisaccharide consisting of N-acetylated amino sugars. D7 reacted with a substructure which can be modified in the B. parapertussis and B. bronchiseptica LPSs by addition of a polymeric O-chain. P1P3 bound to a nonacetylated glucosamine substituted with L-glycero-D-manno-heptose, present in the 'core' of the B. pertussis LPS. These mAbs may be useful for rapid typing of Bordetella in clinical isolates.

Animals↗

Comparison of polysaccharides produced by Myxococcus strains.

Exopolysaccharides were prepared from cultures of four Myxococcus strains grown on solid and in liquid media, and also from the fruiting bodies. Lipopolysaccharides could be extracted with aqueous phenol from the vegetative bacteria, but were absent from microcysts. Mannose and D-glucose were present in all the exopolysaccharides and three of the lipopolysaccharides examined. Other monosaccharides identified in the exopolysaccharides were D-galactose, N-acetylglucosamine and N-acetylgalactosamine. The composition of the lipopolysaccharides was more complex than that of the exopolysaccharides and, in addition to the neutral hexoses and amino sugars, rhamnose was identified in two preparations and ribose in another. No lipopolysaccharide preparations contained O-methyl xylose or heptose. The polysaccharides secreted by the bacillary forms grown on solid or in liquid media closely resembled the polysaccharides isolated from the fruiting bodies, in which they provided a matrix surrounding the microcysts. Each pair of polysaccharides contained the same monosaccharides, although in slightly different proportions. Differences were found in preparations from different strains. These results suggest that in the development cycle of the genus Myxococcus, considerable use is made of pre-existing enzyme systems to synthesize the precursors necessary for polysaccharide synthesis. Any specific difference between the polysaccharide produced by the bacilli and that surrounding the microcysts may lie in the fine structure, rather than in the individual components.

Acetylgalactosamine↗

Aspects of the pathogenicity of some oral and other haemophili.

The pathogenicity of the predominantly non-capsulated, V-factor requiring haemophili that are commonly recovered from oral infections has been explored by studies of their endotoxins and infectivity as compared with those of Haemophilus influenzae. Similar yields of endotoxin (2.40-2.59% w/w) were obtained from all the haemophili examined except H. haemolyticus (1.61% w/w). The lipopolysaccharide (LPS) extracts all contained heptoses but not 2-keto-3-deoxyoctonate (KDO). The fatty acid compositions of the lipid-A fractions were essentially similar but comprised 76% of the LPS in the H. influenzae type d strain tested and only 20% in the H. influenzae type b strain and some strains of H. parainfluenzae. All extracts contained arachidic acid, which may be unique to haemophili. The endotoxins from all strains produced characteristic pyrogenic and polymorph effects in rabbits. The endotoxins from the pharyngeal X- and V-factor-requiring strains had LD50 values for actinomycin-D-sensitised mice of 2.4-2.7 micrograms/kg, and were about eight times more potent than those from the oral V-factor-requiring strains (LD50 values 17.2-22.4 micrograms/ml). Approximately ten thousand times more free endotoxin was detected in broth cultures of H. influenzae type b than in those of oral haemophili, and this greater endotoxin release was not associated with a greater degree of autolysis. Endotoxin release from viable cells may be important in the pathogenicity of this organism. H. influenzae type b was much more potent in producing infection in chambers implanted subcutaneously in guinea pigs than were oral strains of haemophili; only 10 type b organisms were required, compared with 9 X 10(5) of H. parainfluenzae. However, in infections maintained for 90 days, the numbers of haemophili--c. 10(7)/ml of chamber fluid--were similar for all the test strains. Thus, although the oral haemophili lack special attributes of invasiveness and resistance to host defences, they are not devoid of pathogenic potential and, if allowed to proliferate, may become an important element in an infection.

Animals↗