Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “POLYSACCHARIDES”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 55 records · Page 3Linked to original sources
PubMed1968

Chemical and immunological studies on mycobacterial polysaccharides. 1. Purification and properties of polysaccharides from human tubercle bacilli.

Defatted human tubercle bacilli, Aoyama B strain, were extracted with 0.1 n NaOH for 24 hr, and the crude polysaccharide fraction was precipitated by the addition of 5 volumes of ethyl alcohol. A yield of 17.8 g of crude polysaccharides was obtained from 800 g of bacilli. The crude polysaccharide was further fractionated into seven fractions by fractional precipitation with ethyl alcohol. Each fraction was purified by successive chromatography on Dowex 50 and diethylaminoethyl cellulose, and by gel filtration on Sephadex G-75 and G-200. Optical rotation and gas chromatographic analyses of purified polysaccharide showed that these polysaccharides contained glucan mannan, arabinomannan, and arabinogalactan. Each polysaccharide was almost completely free from nitrogen, and no tuberculin reaction was produced by 100 mug of each material. Arabinomannan and arabinogalactan showed precipitin reaction, complement fixation, and passive hemagglutination reaction with rabbit antiserum against heat-killed whole bacilli (Aoyama B). In guinea pigs sensitized with Aoyama B bacilli, arabinomannan and arabinogalactan provoked anaphylactic shock when injected intravenously, and Arthus type reaction when injected intracutaneously. With the use of rabbit antiserum, arabinomannan and arabinogalactan showed passive anaphylactic shock, passive cutaneous anaphylaxis, and Prausnitz-Küstner type reactions in guinea pigs. By immunodiffusion analysis, it was shown that the antigenic determinant of arabinomannan was different from that of arabinogalactan.

Animals↗
PubMedDate not supplied

The course of cryptococcal capsular polysaccharide antigenemia/human cryptococcal polysaccharide elimination kinetics.

The detection of cryptococcal polysaccharides in the serum is diagnostic of cryptococcosis in the absence of rheumatoid factor. The significance of the continued detection of this antigen in the serum during antifungal therapy is not known. Prolonged antigenemia might indicate ongoing active infection, delayed clearance of the polysaccharides from the blood, or continued release of the polysaccharide antigens from a reservoir of nonviable organisms. In seven cases the cryptococcosis with prolonged and high levels of cryptococcal polysaccharide antigenemia, the courses of antigenemia were determined. During the convalescent phase, the T 1/2's were approximately 48 hours for the antigen clearance in all the cases studied. The polysaccharide antigens recovered from the serum of one patient had molecular weights of greater than 200,000 daltons. In rabbits, a single intravenous injection of cryptococcal capsular polysaccharides showed a similarly slow clearance of the antigen with a T 1/2 of approximately 24 to 48 hours. These data suggest that adequately treated cases of cryptococcosis may have a predictable rate of antigen clearance from the serum during convalescence.

Animals↗
PubMed1998

Extracellular polysaccharides and polysaccharide-containing biopolymers from Azospirillum species: properties and the possible role in interaction with plant roots.

This paper reviews the results obtained in studies of the extracellular polysaccharides, lipopolysaccharide-protein complexes, polysaccharide-lipid complexes, lipopolysaccharides, and O-specific polysaccharides from bacteria of the genus Azospirillum. On the basis of present knowledge, the possible roles of the extracellular polysaccharides and polysaccharide-containing complexes of azospirilla in interaction with the roots of plants are discussed. Some pieces of evidence are considered in light of the lectin hypothesis originally proposed for the legume-Rhizobium symbiosis. In the context of these views of Azospirillumcereal associative pairs, a key process at the early stages of the interaction is the specific reaction of cereal root lectins with the extracellular polysaccharide components, containing N-acetyl-D-glucosamine as part of their structure.

Azospirillum↗
PubMed1994

Functional activity of antibodies to the group B polysaccharide of group B streptococci elicited by a polysaccharide-protein conjugate vaccine.

Group B streptococci (GBS) are a major cause of sepsis and meningitis in infants. While antibodies directed to the type-specific GBS capsule have been shown to be protective, it is less clear whether antibodies to the group B polysaccharide, a noncapsular, cell wall-associated antigen, may play a role in immunity. To investigate the functional activity of group B polysaccharide-specific antibodies, we tested sera from rabbits vaccinated with group B polysaccharide coupled to tetanus toxoid (B-TT). Anti-B-TT was weakly opsonic in vitro for a highly encapsulated type III strain, while antiserum elicited by vaccination with type III capsular polysaccharide linked to tetanus toxoid (III-TT) was a very effective opsonin. In contrast to anti-III-TT, anti-B-TT given before or after bacterial challenge was only marginally effective in protecting newborn mice against lethal infection with type III GBS. The number of C3 molecules bound to type III GBS was augmented by anti-III-TT but not by high antibody concentrations of anti-B-TT. These results suggest that the difference in opsonic activity between anti-B-TT and anti-III-TT may be due to a difference in their ability to deposit C3. In addition, the maximum number of antibody molecules bound to the bacterial surface was greater for anti-III-TT than for anti-B-TT. That anti-B-TT binds to fewer sites than anti-III-TT may explain the differences in complement activation and in opsonic and protective efficacy of antibodies to group B polysaccharide compared with antibodies to the type-specific capsular polysaccharide.

Animals↗
PubMed2003

The polysaccharide from Tamarindus indica (TS-polysaccharide) protects cultured corneal-derived cells (SIRC cells) from ultraviolet rays.

The aim of this work was to investigate the possible protective effect of a new viscosising agent, TS-polysaccharide, on corneal-derived cells (SIRC) exposed to ultraviolet-B rays. To verify this, SIRC cells were first exposed, in the absence or in the presence of TS-polysaccharide (1% w/v), for 9 s at the UV-B source and then post-incubated for 45 min at 37 degrees C. After this period the hydrogen peroxide (H(2)O(2)) accumulated in the medium and the concentration of 8-hydroxy-2'-deoxy-guanosine (8-OHdG) in cell DNA was measured. In addition, the amount of (3)H-methyl-thymidine incorporated in cellular DNA was evaluated after 18 h from irradiation. Our results show that cells exposed to UV-B rays accumulate H(2)O(2), and have higher levels of 8OHdG and a lower amount of (3)H-methyl-thymidine incorporated in DNA than control cells. In the presence of TS-polysaccharide, the H(2)O(2) and 8-OHdG accumulation, and the (3)H-methyl-thymidine incorporation were significantly reduced with respect to the values measured in cells exposed in the absence of the polysaccharide. We propose a protective role of the polysaccharide in reducing UV-B derived DNA damage to eye cells. This finding could be of some clinical importance when the polysaccharide is used as a delivery system for ophthalmic preparations.

8-Hydroxy-2'-Deoxyguanosine↗
PubMed1971

Capsulation of pneumococcus with soluble cell wall-like polysaccharide. II. Nonidentity of cell wall and soluble cell wall-like polysaccharides derived from the same and from different pneumococcal strains.

Methods are described for the separation of the C or cell wall polysaccharide from the C(s) or soluble C-like capsular polysaccharide of C(s) pneumococcal strains. Immunologic analysis has shown that both the C and C(s) polysaccharides of a variety of pneumococcal strains are heterogeneous and that the dissimilarities appear to reside in the mucopeptide portion of the molecule or in the region of its attachment to the teichoic acid moiety of the molecule rather than in the teichoic acid fraction. Differences of the type described have been observed in the C polysaccharides of wild-type capsulated strains of several types, in those of independently isolated noncapsulated variants derived from a single strain of a given capsular type, and in the C and C(s) polysaccharides of spontaneous mutant or transformed strains of pneumococci producing capsules of C(s) polysaccharide.

Animals↗
PubMed2000

Bacteroides fragilis NCTC9343 produces at least three distinct capsular polysaccharides: cloning, characterization, and reassignment of polysaccharide B and C biosynthesis loci.

Bacteroides fragilis produces a capsular polysaccharide complex (CPC) that is directly involved in its ability to induce abscesses. Two distinct capsular polysaccharides, polysaccharide A (PS A) and PS B, have been shown to be synthesized by the prototype strain for the study of abscesses, NCTC9343. Both of these polysaccharides in purified form induce abscesses in animal models. In this study, we demonstrate that the CPC of NCTC9343 is composed of at least three distinct capsular polysaccharides: PS A, PS B, and PS C. A previously described locus contains genes whose products are involved in the biosynthesis of PS C rather than PS B as was originally suggested. The actual PS B biosynthesis locus was cloned, sequenced, and found to contain 22 genes in an operon-type structure. A mutant with a large chromosomal deletion of the PS B biosynthesis locus was created so that the contribution of PS B to the formation of abscesses could be assessed in a rodent model. Although purified PS B can induce abscesses, removal of this polysaccharide does not attenuate the organism's ability to induce abscesses.

Abscess↗
PubMed1986

[Antigenic polysaccharides of bacteria. 18. Structure of O-specific polysaccharide chains of Pseudomonas aeruginosa 05 (Lányi) lipopolysaccharide].

Polysaccharide chains of P. aeruginosa O5a, b, c, O5a, b, d and O5a, d (Lányi classification) lipopolysaccharides contain D-xylose, N-acetyl-D-fucosamine (FucNAc) and a derivative of 5,7-diamino-3,5,7,9-tetradeoxy-L-glycero-L-manno-nonulosonic acid (pseudaminic acid, PseN2) carrying acetyl or (R)-3-hydroxybutyryl (Hb) and formyl (Fm) groups as N-acyl substituents. Degradation of the lipopolysaccharides with dilute acetic acid caused depolymerisation of the polysaccharide chains as a result of cleavage of glycosidic linkage of pseudaminic acid to give trisaccharides representing chemical repeating units of the polysaccharides. Basing on analysis of the trisaccharides using 1H and 13C NMR spectroscopy and mass-spectrometry, the following structures of the polysaccharide chains were established: (Formula: see text). O5a, d polysaccharide is identical to P. aeruginosa immunotype 6 O-specific polysaccharide.

Antigens, Bacterial↗
PubMed2001

Structure of the O-specific polysaccharide of Proteus vulgaris O4 containing a new component of bacterial polysaccharides, 4,6-dideoxy-4.

A high-molecular-mass O-specific polysaccharide was obtained by mild acid degradation of Proteus vulgaris O4 lipopolysaccharide followed by GPC. The polysaccharide was studied by chemical methods along with 1H and 13C NMR spectroscopy, including two-dimensional COSY, TOCSY, NOESY, H-detected 1H,13C HMQC, and 1H,13C HMBC experiments. Solvolysis of the polysaccharide with trifluoromethanesulfonic (triflic) acid resulted in a GlcpA-(1 --> 3)-GlcNAc disaccharide and a novel amino sugar derivative, 4,6-dideoxy-4-[N-[(R)-3-hydroxybutyryl]-L-alanyl]amino-D-glucose [Qui4N(HbAla)]. On the basis of the data obtained, the following structure of the tetrasaccharide repeating unit of the O-specific polysaccharide was established: --> 4)-beta-D-GlcpA-(1 --> 3)-beta-D-GlcpNAc-(1 --> 2)-beta-D-Quip4N(HbAla)-(1 --> 3)-alpha-D-Galp-(1 -->. This structure is unique among the O-specific polysaccharides, which is in accordance with classification of the strain studied in a separate Proteus serogroup.

Animals↗
PubMed1983

Immunoelectrophoretic characterization of the molecular weight polydispersion of polysaccharides in multivalent bacterial capsular polysaccharide vaccines.

The molecular weight polydispersion of single antigens present in multivalent bacterial capsular polysaccharide vaccines has been characterized by an immunoelectrophoretic method. Chromatographic effluents from Sepharose gel of bacterial capsular polysaccharide vaccines were tested by fused-rocket immunoelectrophoresis and the distribution coefficient (Kd) of each polysaccharide present in the mixture was calculated. The method appeared to be efficient and reproducible. However, different Kd values were obtained by immunoelectrophoretic and chemical or physical analysis of the chromatographic effluents of each single polysaccharide component. The use of this immunoelectrophoretic procedure was extended to the potency control of multivalent meningococcal and pneumococcal polysaccharide vaccines in order to detect changes in the molecular weight polydispersion of each antigen with time.

Bacterial Vaccines↗
PubMed1997

Polysaccharide components from the scape of Musa paradisiaca: main structural features of water-soluble polysaccharide component.

Polysaccharide components present in the pseudo-stem (scape) of M. paradisiaca were purified from acetone powder of the scape by delignification followed by extraction with aqueous solvents into water soluble polysaccharide (WSP), EDTA-soluble polysaccharide (EDTA-SP), alkali-soluble polysaccharide (ASP) and alkali-insoluble polysaccharide (AISP) fractions. Sugar compositional analysis showed that WSP and EDTA-SP contained only D-Glc whereas ASP contained D-Glc, L-Ara and D-Xyl in approximately 1:1:10 ratio, respectively, and AISP contained D-Glc, L-Ara and D-Xyl in approximately 10:1:2 ratio, respectively. WSP was further purified by complexation with iso-amylalcohol and characterized by specific rotation, IR spectroscopy, Iodine affinity, ferricyanide number, blue value, hydrolysis with alpha-amylase and glucoamylase, and methylation linkage analysis, and shown to be a amylopectin type alpha-D-glucan.

Carbohydrate Conformation↗
PubMed1997

Identification of specific recognition molecules on murine mononuclear phagocytes and B lymphocytes for Vi capsular polysaccharide: modulation of MHC class II expression on stimulation with the polysaccharide.

Vi bacterial polysaccharide is a homopolymer of alpha 1-4 N-acetyl polygalacturonic acid with variable O-acetylation at position C-3 and forms a capsule around many bacteria. It has been referred to as the virulence factor of Salmonella typhi and is also a candidate vaccine against typhoid fever. The present study reports the interaction of this polysaccharide with murine mononuclear phagocytes and lymphocytes, and with human monocytes. Vi showed a dose-dependent binding to the murine monocyte cell lines WEHI-274.1 and J774. This binding was abrogated if the polysaccharide was deacetylated, suggesting involvement of acetyl groups in this interaction. Vi also bound to the murine B-cell lymphoma line A20, to peritoneal exudate cells and to a lesser degree to spleen cells and thymocytes from BALB/c mice. The polysaccharide also interacted with the human histiocytic lymphoma line U937 but not with the human monocyte cell line THP-1. Stimulation with Vi led to up-regulation of surface major histocompatibility complex (MHC) class II expression on A20 cells. Immunoprecipitation of Vi-bound molecules from cell surface biotinylated A20 and WEHI-274.1 revealed two bands with MW of about 32,000 and 36,000. The study demonstrates that Vi capsular polysaccharide can interact with mononuclear phagocytes and lymphocytes through specific cell surface molecules and modulate MHC class II expression.

Animals↗
PubMed1972

Distribution of enzymes forming polysaccharide from sucrose and the composition of extracellular polysaccharide synthesized by Streptococcus mutans.

The distribution of polysaccharide-forming activity from sucrose was investigated in cultures of three strains of Streptococcus mutans by using an assay which conveniently determines total polysaccharide. The enzymatic activity for polysaccharide formation from sucrose is almost exclusively extracellular. The ratio of the fructan to glucan in the polysaccharide differs among the three strains investigated. The enzymatic activity for the formation of polysaccharide from sucrose has been shown to be bound to the cell-free polymer itself.

Binding Sites↗
PubMed2005

Effects of absorption with pneumococcal type 22F polysaccharide on maternal, cord blood, and infant immunoglobulin G antipneumococcal polysaccharide antibodies.

The aim of this study was to evaluate the effect of absorption with pneumococcal type 22F polysaccharide on antipneumococcal antibody titers in unimmunized Chilean pregnant women and on antibodies in their offspring at birth and 3, 6, and 12 months of age. Sera from 10 healthy pregnant women and from their offspring at birth and at 3, 6, and 12 months of age were studied. Immunoglobulin G antibodies against serotypes 1, 3, 4, 5, 6B, 9V, 14, 18, 19F, and 23F were measured by a standardized enzyme-linked immunosorbent assay method. All sera were absorbed with polysaccharide C, and aliquots of each serum were absorbed with polysaccharide 22F. Individual results were expressed in mug/ml based on the standard serum pool 89-SF. Absorption with polysaccharide 22F reduced antibody concentrations in all samples and to all 10 serotypes studied. Reduction was highest in maternal sera and in cord blood, but it was also present at 3, 6, and 12 months of age. The percent reduction ranged from 24% for serotype 14 to 50% for serotype 1 in maternal samples and from 20% for serotype 18C to 49% for serotype 4 in cord blood samples. The percentages of transplacental transmission were similar for nonabsorbed and absorbed maternal fetal pairs. Absorption with serotype 22F had a significant impact on antipneumococcal antibody concentrations in unimmunized pregnant women and in their offspring. Our results suggest that absorption with 22F polysaccharide needs to be performed in studies of transplacental transmission of antipneumococcal antibodies.

Absorption↗
PubMed1973

Polysaccharides of the genus Bacillus cross-reactive with the capsular polysaccharides of Diplococcus pneumoniae type 3, Haemophilus influenzae type b, and Neisseria meningitidis group A.

We studied 174 strains of the genus Bacillus for cross-reacting antigens to the capsular polysaccharides of groups A and C meningococcus, types I and III pneumococcus, and Haemophilus influenzae type b. Cross-reactions were detected by immunodiffusion in agarose gel by using type-specific antisera and confirmed by absorption and inhibition experiments. Of 20 Bacillus pumilis strains, six had an antigen cross-reacting with group A meningococcal polysaccharide. Other cross-reactions included one strain of B. pumilis with H. influenzae type b, one of B. cereus var. mycoides with pneumococcus type III, and one of B. alvei with both type b and SIII polysaccharides. These cross-reacting antigens are polysaccharides of vegetative cells and may be extracellular in location. Because these bacilli have antigens cross-reacting with the virulence factors of pyogenic bacteria, they may, as normal flora, be an antigenic stimulus for "natural" serum anti-capsular antibodies to the type b Haemophilus and group A meningococcus polysaccharides.

Antigens, Bacterial↗
PubMed2006

CRM197-conjugated serogroup C meningococcal capsular polysaccharide, but not the native polysaccharide, induces persistent antigen-specific memory B cells.

Neisseria meningitidis is one of the leading causes of bacterial meningitis and septicemia in children. Vaccines containing the purified polysaccharide capsule from the organism, a T cell-independent antigen, have been available for decades but do not appear to provide protection in infancy or immunologic memory as measured by antibody responses. By contrast, T cell-dependent serogroup C protein-polysaccharide conjugate vaccines protect against serogroup C meningococcal disease from infancy onward and prime for immunologic memory. We compared the magnitude and kinetics of plasma cell and memory B-cell responses to a meningococcal plain polysaccharide vaccine and a serogroup C glycoconjugate vaccine in adolescents previously primed with the conjugate vaccine. Plasma cell kinetics were similar for both vaccines, though the magnitude of the response was greater for the glycoconjugate. In contrast to the glycoconjugate vaccine, the plain polysaccharide vaccine did not induce a persistent immunoglobulin G (IgG) memory B-cell response. This is the first study to directly show that serogroup C meningococcal glycoconjugate vaccines induce persistent production of memory B cells and that plain polysaccharide vaccines do not, supporting the use of the conjugate vaccine for sustained population protection. Detection of peripheral blood memory B-cell responses after vaccination may be a useful signature of successful induction of immunologic memory during novel vaccine evaluation.

Adolescent↗
PubMed2000

Quantification of C-polysaccharide in Streptococcus pneumoniae polysaccharides by high-performance anion-exchange chromatography with pulsed amperometric detection.

A sensitive method, using high-performance anion-exchange chromatography with pulsed amperometric detection (HPAEC-PAD) has been developed for measurement of the C-polysaccharide contamination in Streptococcus pneumoniae capsular polysaccharides, which are part of the polysaccharides based vaccines for the prevention of pneumococcal infections. This method, based on the quantification by HPAEC-PAD of the ribitol released by aqueous hydrofluoric acid (HF) followed by trifluoro acid hydrolysis (TFA) of the pneumococcal polysaccharides is simple and provides both a qualitative and quantitative method for control of the polysaccharides.

Chromatography, High Pressure Liquid↗
PubMed1989

[Use of group A-specific polysaccharide antigen conjugated with protein carrier for detection of specific anti-polysaccharide antibodies].

Group-A specific polysaccharide antigen has been obtained by extraction of streptococcal suspension using 4N NaNO2 and glacial acetic acid, conjugated with bovine serum albumin using CNBr. Testing of the preparation with a set of rabbit anti-sera by enzyme immunoassay (EIA) and passive hemagglutination reaction (PHR) revealed its antigenic specificity both in direct experiments and in N-acetyl-D-glucosamine absorption. Forty-seven sera of EIA-studied individuals and 35 sera of PHR-studied ones, all with group-specific polysaccharide antigen, were examined. Immune reactions showed the broad spectrum of antibody titres in the studied sera. Complete correlation of anti-polysaccharide antibodies detected by the two techniques was observed in the sera with high specific antibody titres. A possibility to use the obtained group-A specific polysaccharide antigen to detect anti-polysaccharide antibodies in the sera of streptococcal infection patients is discussed.

Animals↗