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PubMed1994

Structure and composition of biological slimes on paper and board machines.

Biological slimes (biofilms) collected from the wet end of paper and board machines were examined by electron microscopy and analyzed for fatty acid composition, neutral sugar composition, and ATP. Electron microscopy revealed minuscule prokaryotic organisms (diameter, 0.2 to 0.4 mum). Larger cells morphologically resembling Sphaerotilus and Leptothrix spp. were found in slimes from machines using recycled fiber or unbleached pulp. The bacteria were embedded in a slimy matrix and often contained reserve materials microscopically resembling poly-beta-hydroxybutyrate and glycogen. Fatty acid analysis of the slimes revealed bacterial signature fatty acids in concentrations equivalent to the presence of 2 x 10 to 2.6 x 10 (average, 7 x 10) bacterial cells (live and dead) per g (dry weight) of slime. The slimes contained several known components of bacterial polysaccharides in addition to glucose, indicating that the slime body consisted of bacterial polysaccharides. The slimes contained uronic acids equivalent to a binding capacity of 12.5 to 50 mumol of divalent cations per g (dry weight) of slime. The uronic acid-containing polysaccharides may be responsible for the accumulation of heavy metals in the slime. Calculation of the ATP contents of the slimes resulted in an estimate of 5 x 10 cells per g (dry weight) of slime when calibrated with pure bacterial cultures isolated from the slimes. From electron micrographs, an estimate ranging from 1 x 10 to 1.5 x 10 (average, 4 x 10) cells per g (dry weight) of slime was obtained.

Journal Article↗
PubMed1985

Biochemical, microbiologic, and clinical comparisons between two dentifrices that contain different mixtures of sugar alcohols.

It has been customary to think that in a dentifrice only a few of its ingredients would be active and have clinically significant effects on dental caries, oral hygiene, and the levels of caries-inducive microorganisms or harmful plaque metabolic products. Therefore, most of the emphasis has been placed on the type of fluorine compounds, abrasives, or similar dentifrice ingredients. This study shows that such common dentifrice components as the humectants, which contribute to the texture, rheologic characteristics, and shelf life of the product, also may affect the type of dental plaque grown on the tooth surfaces between toothbrushings or during long-term neglect of toothbrushing or of oral hygiene. Commonly used humectants include sorbitol, a sugar alcohol of the hexitol type, which is used often in sugarless candies. This study showed that when sorbitol in a dentifrice was replaced by xylitol, a sugar alcohol of the pentitol type, the dental plaque of human subjects contained more ammonia and significantly less bacterial polysaccharides. It is accepted generally that ammonia neutralizes plaque acids and that bacterial polysaccharides are involved in promoting caries. Xylitol-containing dentifrice also reduced the saliva levels of S mutans. The results further indicated that if sorbitol and xylitol could be compared in a short-term dentifrice study that relied on subjective and coarse plaque determinations only, no differences between those dentifrices would be found necessarily. To demonstrate the differences between the experimental dentifrices used in this study, it was necessary to analyze specific plaque components and the salivary levels of S mutans.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed2000

T cells activated by zwitterionic molecules prevent abscesses induced by pathogenic bacteria.

Immunologic paradigms classify bacterial polysaccharides as T cell-independent antigens. However, these models fail to explain how zwitterionic polysaccharides (Zps) confer protection against intraabdominal abscess formation in a T cell-dependent manner. Here, we demonstrate that Zps elicit a potent CD4+ T cell response in vitro that requires available major histocompatibility complex class II molecules on antigen-presenting cells. Specific chemical modifications to Zps show that: 1) the activity is specific for carbohydrate structure, and 2) the proliferative response depends upon free amino and carboxyl groups on the repeating units of these polysaccharides. Peptides synthesized to mimic the zwitterionic charge motif associated with Zps also exhibited these biologic properties. Lysine-aspartic acid (KD) peptides with more than 15 repeating units stimulated CD4+ T cells in vitro and conferred protection against abscesses induced by bacteria such as Bacteroides fragilis and Staphylococcus aureus. Evidence for the biologic importance of T cell activation by these zwitterionic polymers was provided when human CD4+ T cells stimulated with these molecules in vitro and adoptively transferred to rats in vivo conferred protection against intraabdominal abscesses induced by viable bacterial challenge. These studies demonstrate that bacterial polysaccharides with a distinct charge motif activate T cells and that this activity confers immunity to a distinct pathologic response to bacterial infection.

Abscess↗
PubMed2005

Autoantibodies that bind glomeruli: cross-reactivity with bacterial antigen.

OBJECTIVE: Systemic lupus erythematosus (SLE) is characterized by the production of multiple autoantibodies. Anti-DNA antibodies are associated with glomerulonephritis in SLE. It has been shown that anti-DNA antibodies cross-react with bacterial polysaccharide and, thus, might be elicited by microbial exposure. Non-DNA-binding antibodies also contribute significantly to the pathogenesis of lupus nephritis. The goal of this study was to characterize non-DNA-binding, kidney-binding antibodies. METHODS: We generated a combinatorial library derived from spleen cells of a patient with SLE who had just previously received pneumococcal vaccine. The phage library was used in an in vivo biopanning technique to identify non-DNA-binding, kidney-binding antibodies. Antibodies were then analyzed for binding to bacterial polysaccharide and to renal antigens. RESULTS: Eight antibodies were characterized that bound glomeruli, but not DNA. All antibodies isolated by this protocol were IgG class, suggesting that there is affinity maturation for glomerular binding. Four of the antibodies cross-reacted with pneumococcal polysaccharide. Six of the antibodies bound to renal antigens that have previously been reported to be cross-reactive with DNA; the other 2 bound to histone. CONCLUSION: This study suggests that both DNA-binding and non-DNA-binding antibodies in SLE may be elicited by the same bacterial antigens.

Antibodies, Antinuclear↗
PubMed1984

Preparation of human hyperimmune globulin to Haemophilus influenzae b, Streptococcus pneumoniae, and Neisseria meningitidis.

As a first step in exploring the feasibility of passive antibody prophylaxis and therapy of serious infections caused by common encapsulated bacteria, we have immunized healthy adults with Haemophilus influenzae type b vaccine, 14-valent pneumococcal vaccine, and meningococcal group A and C vaccine; collected plasma by repeated pheresis; and purified a hyperimmune globulin termed bacterial polysaccharide immune globulin by the cold-ethanol fractionation method of Cohn and Oncley. Specific antibacterial antibody concentrations were measured in individual donors before and after immunization. In addition, antibody concentrations were measured in plasma pools prepared from immunized donors and from unimmunized controls and in the immunoglobulin-containing Cohn-Oncley fractions II and III derived from the respective plasma pools. A comparison of Cohn-Oncley fractions II, which contain primarily immunoglobulin G and which are used therapeutically as immune globulin, revealed that antibody to H. influenzae type b was enriched 15.3-fold and that antibody to meningococcal serogroups and pneumococcal types was enriched a mean of 4.4-fold (range, 1.2- to 9.9-fold). Enrichment of antibacterial antibody in Cohn fraction III, which contains substantial amounts of immunoglobulin M and immunoglobulin A in addition to immunoglobulin G, closely paralleled that in fraction II. Only antibodies to pneumococcal types 1 and 7 were increased disproportionately in fraction III. Based on the clinical experience that conventional immune serum globulin at a dose of 100 mg/kg protects agammaglobulinemic patients for ca. 1 month, we estimate that bacterial polysaccharide immune globulin, in similar dosage, will provide protection from systemic H. influenzae type b infection for 4 to 6 months and from pneumococcal and meningococcal infections for 3 to 4 months.

Antibodies, Bacterial↗
PubMed1990

Relationship between serum IgG2 concentrations and antibody responses to pneumococcal polysaccharides in children with chronic chest symptoms.

We measured IgG-class antibodies to 12 pneumococcal antigens pre- and post-immunization with polyvalent pneumococcal vaccine in 31 children who had experienced chronic chest symptoms. The purpose of the study was to determine the relation of IgG subclasses, especially IgG2, to the subjects' antibody responses to bacterial polysaccharide antigens, to see if measuring IgG subclasses would predict these responses. Twenty-nine children (90%) had low or low-normal levels of one or more IgG subclasses, including 20 out of 31 (65%) with low or low-normal levels of IgG2. Children studied had a relatively poor increase in levels of antibody to 10 of the 12 pneumococcal vaccine antigens investigated. Both pre- and post-immunization antibody levels were related to pre-immune serum concentrations of IgG2. Pre-immunization antibody levels were strongly related to post-immunization levels; when post-immunization antibody levels were adjusted for pre-immunization levels by partial correlation, the correlation between anticapsular antibody level post-immunization and IgG2 was no longer significant. Thus, in children with chronic chest symptoms, levels of antibody measured at a random interval after natural exposure to these bacterial polysaccharide antigens are related to levels of IgG2 subclass, but antibody increases after vaccination appear to be affected more by other factors.

Adolescent↗
PubMed2002

Defining the potential impact of conjugate bacterial polysaccharide-protein vaccines in reducing the burden of pneumonia in human immunodeficiency virus type 1-infected and -uninfected children.

BACKGROUND: The evaluation of bacterial conjugate vaccines in preventing pneumonia requires the definition of suitable outcome measures against which their use can be evaluated. One such possible outcome measure is alveolar consolidation confirmed by chest radiograph (CXR). OBJECTIVE: To define the CXR presentation in relation to identified bacterial and respiratory viral pathogens among HIV-1-infected and -uninfected children. METHODS: The CXRs of 1186 of 1434 children hospitalized with severe lower respiratory tract infection were evaluated for the presence of alveolar consolidation (homogenous airspace infiltrate), bronchopneumonia (patchy airspace consolidation) or other CXR findings. Children were also investigated for bacterial infection by blood culture in 1364 of 1434 episodes and for respiratory viruses in 990 of 1434 episodes by immunofluorescein monoclonal antibody assays. RESULTS: The prevalence of HIV-1 infection among children who had CXRs in the study was 527 (46.2%) of 1142. Alveolar consolidation was more common in HIV-1-infected (63.7%) than in HIV-uninfected children (42.4%, P < 10(-5)) whereas bronchopneumonic changes (29.0% vs. 38.0%, P = 0.001) or a normal CXR occurred in 7.0 vs. 18.2% (P < 10(-5)) of HIV-1-infected and -uninfected children, respectively. Alveolar consolidation was the main CXR presentation in HIV-1-infected (78.6%) and HIV-uninfected children (64.9%, P = 0.14) with all-cause bacteremic pneumonia as well as those with bacteremic Streptococcus pneumoniae pneumonia (76.9% vs. 83.3%, respectively; P = 0.99). Respiratory virus-associated lower respiratory tract infection, however, was more likely to present with alveolar consolidation in HIV-1-infected (55.8%) than in HIV-uninfected (36.1%, P = 0.02) children. CONCLUSION: Although alveolar consolidation may be a useful tool in defining both the efficacy and burden of bacterial pneumonia in HIV-1-uninfected children, this may not be so for HIV-1-infected children. The higher occurrence of respiratory virus-associated alveolar consolidation, possibly coupled with Pneumocystis carinii pneumonia, may be significant confounders in the interpretation of CXR in HIV-1-infected children, limiting the use of alveolar consolidation as an outcome measure when evaluating the efficacy of bacterial conjugate vaccines in HIV-1-infected children.

Bacterial Proteins↗
PubMed2004

Bacterial polysaccharide-protein conjugate vaccines.

Following demonstration that chemical conjugation of polysaccharide antigens to proteins could enhance their immunogenicity in the 1920s, interest in this approach to primary prevention of bacterial infections waned with the development and widespread use of antibiotics. Emergence of resistant bacteria rekindled interest in the late 20th century, which saw extremely rapid development and implementation of several vaccines which are already rapidly changing the epidemiology of childhood infections with Haemophilus influenzae type b, Streptococcus pneumoniae and Neisseria meningitidis. Others such as Group B streptococcus and Salmonella typhi infections may soon follow. However, several important questions about the immunology of these antigens remain unanswered and the long-term implications of reducing or eliminating the circulation of organisms which are more commonly nasopharyngeal commensals than pathogenic invaders are uncertain.

Adolescent↗
PubMed1992

Effects of haemorrhage on bacterial antigen specific pulmonary plasma cell function.

Nosocomial pneumonia is frequent after haemorrhage and trauma, and often contributes to multiple organ system failure, morbidity and mortality in this setting. Although the percentages and numbers of bacterial polysaccharide antigen-specific pulmonary B cell clonal precursors are markedly decreased after haemorrhage, the effects of haemorrhage on pulmonary plasma cells actually producing antibody to these antigens are unknown. To investigate this question, the numbers of intraparenchymal pulmonary plasma cells producing antibody against the bacterial polysaccharide antigen levan (from Aerobacter levanicum) as well as bacterial antigen specific secretory IgA (sIgA) titres in the lungs were determined at various time points after 30% blood volume haemorrhage. Reduced numbers of bacterial antigen specific pulmonary plasma cells were found for more than 21 days following haemorrhage. An almost complete disappearance from the lungs of levan specific plasma cells occurred between 3 and 21 days after blood loss. Titres of bacterial antigen specific sIgA in the lungs were decreased starting at 3 days post-haemorrhage and remained significantly depressed for more than 35 days after blood loss. These results demonstrate that haemorrhage produces profound and long-lasting suppression in bacterial antigen-specific pulmonary plasma cell function. Because these effects do not occur immediately post-haemorrhage, immunization techniques able to enhance bacterial antigen specific sIgA titres at pulmonary surfaces may be able to increase resistance to nosocomial pneumonia if administered shortly after injury and blood loss.

Animals↗
PubMed1996

[Dextran-induced anaphylactoid reactions in two patients with gastrointestinal cancer].

We report dextran-induced anaphylactoid reactions (DIAR) subsequent to rapid infusion of Rheomacrodex (dextran 40) in two patients, a 67 year old man with gastric cancer undergoing distal gastrectomy and a 47 year old man with transverse colon cancer undergoing colectomy. Both showed sudden tachycardia, hypotension and skin flush, which were treated with epinephrine or etilephrine administration. Most cases of severe DIAR are immune complex anaphylaxis mediated by dextran-reactive antibodies (DRA) of the IgG class, which are considered to arise mainly in response to immunization with dextran-cross-reactive bacterial polysaccharides in the gastrointestinal tract. High titers of DRA have previously been reported in gastric ulcer patients with pyloric stenosis, suggesting bacterial polysaccharides permeation through the luminal wall which may easily occur in the presence of local inflammation or ulcer. Although serum DRA titers in our patients have not been examined, inflammation or ulcer around the tumor might have played a role in producing high titers of DRA. In patients suspected of gastrointestinal ulcer or inflammation, including cancer, dextran administration is not preferable or should be avoided, unless hapten-dextran preparation is used for the prophylaxis of severe DIAR.

Aged↗
PubMed2004

Quantification of O-acetyl, N-acetyl and phosphate groups and determination of the extent of O-acetylation in bacterial vaccine polysaccharides by high-performance anion-exchange chromatography with conductivity detection (HPAEC-CD).

The O-acetyl groups in meningococcal A and typhoid Vi polysaccharides (PSs) are functional immunogenic epitopes in humans. To quantify and determine the extent of O-acetylation in these and other bacterial vaccine PSs, anion-exchange HPLC methods have been developed for quantification of O-acetyl, N-acetyl, and phosphate groups in the PSs after these groups were hydrolyzed into anions. The O-acetylation in meningococcal A, C, Y and W-135, pneumococcal 9 V and 18C and typhoid Vi PSs were analyzed. The O-acetyl group was selectively released from a PS as acetate by mild alkaline hydrolysis in 10 or 20 mM NaOH at 37 degrees C until maximum release. The acetate in the hydrolysate was then quantified by high-performance anion-exchange chromatography with conductivity detection (HPAEC-CD) after removal of the PS by filtration with a 10,000 molecular-weight-cut-off membrane. Since the extent of O-acetylation on the PSs depends on bacterial species, strains and growth conditions, the N-acetyl group of amino-sugars, phosphate or monosaccharide components of the PSs were also quantified using HPAEC with conductivity or amperometry detection to determine the molar ratios of the O-acetyl group to these components. The average numbers of O-acetyl molecules in one PS repeating unit of the PSs were obtained from the molar ratios. Besides the O-acetyl determination, the pyruvate component in non-O-acetylated pneumococcal type 4 PS was analyzed by the HPAEC method. The HPAEC method can quantify the O-acetyl content in 0.2 microg of the meningococcal C PS and has a sensitivity at least 10 times higher than that of the colorimetric Hestrin assay. The method can be used for routine analysis of O-acetylation of PSs for quality control of vaccine PSs.

Acetylation↗
PubMed1999

Bacterial peptidoglycan polysaccharides in sterile human spleen induce proinflammatory cytokine production by human blood cells.

Peptidoglycan (PG) is the major component of the cell wall of gram-positive bacteria. In vitro, PG isolated from conventional bacterial cultures can induce secretion of proinflammatory cytokines by human monocytes, indicating that PG may be involved in immune responses against infections by gram-positive bacteria. To investigate the biologic activity of PG in human tissues, an improved method was developed to isolate significant amounts of PG from sterile human spleen tissue. Biochemical analysis demonstrated that PG isolated from human spleen is largely intact. Human whole blood cell cultures were able to produce the proinflammatory cytokines tumor necrosis factor-alpha and interleukin-1 and -6 after stimulation with PG isolated from human spleen. Cytokine induction was not sensitive to inhibition by polymyxin B, in contrast to lipopolysaccharide. Collectively, the data show that intact PG in sterile human tissue is biologically active and may induce local proinflammatory cytokine production.

Antigen-Presenting Cells↗
PubMed1986

[Bacterial antigenic polysaccharides. 20. The structure of the O-specific polysaccharide chain of Pseudomonas aeruginosa O(3a),3d,3f (Lányi) lipopolysaccharide].

Mild acid degradation of lipopolysaccharide from Pseudomonas aeruginosa O(3a), 3d, 3f (Lányi classification) afforded O-specific polysaccharide containing N-acetyl-D-fucosamine, 2,3-diacetamido-2,3-dideoxy-D-mannuronic acid, 3-acetamidino-2-acetamido-2,3-dideoxy-L-guluronic and D-mannuronic acid as well as O-acetyl groups. On the basis of O-deacetylation, selective cleavage with anhydrous fluoride, chemical transformation of the oligosaccharides obtained (hydrolysis or reductive deamination of the acetamidino group into acetamido or ethylamino group, respectively) and analysis by 13C NMR spectroscopy, it was concluded that the polysaccharide is built up mainly by trisaccharide repeating units of types A and B in the ratio approximately 2:1: (Formula: see text). The units of both types most probably enter the same polymeric chain. If so, such a hybrid structure can be accounted for by incompleteness of epimerization at C5 of the acetamidino derivative of mannuronic acid at the polymer level in the course of biosynthesis of this polysaccharide.

Antigens, Bacterial↗