scholarly journals Selectively Charged and Zwitterionic Analogues of the Smallest Immunogenic Structure of Streptococcus Pneumoniae Type 14

Molecules ◽  
2019 ◽  
Vol 24 (18) ◽  
pp. 3414 ◽  
Author(s):  
Tiziana Gragnani ◽  
Doretta Cuffaro ◽  
Silvia Fallarini ◽  
Grazia Lombardi ◽  
Felicia D’Andrea ◽  
...  
Keyword(s):  
Streptococcus Pneumoniae ◽  
Specific Antibody ◽  
Capsular Polysaccharide ◽  
Negative Charge ◽  
Positive Charge ◽  
Research Community ◽  
Competitive Elisa ◽  
Structural Variations ◽  
Immunological Properties ◽  
Neutral Compound

Zwitterionic polysaccharides (ZPs) have been shown in recent years to display peculiar immunological properties, thus attracting the interest of the carbohydrate research community. To fully elucidate the mechanisms underlying these properties and exploit the potential of this kind of structures, in depth studies are still required. In this context, the preparation of two cationic, an anionic, as well as two zwitterionic tetrasaccharide analogues of the smallest immunogenic structure of Streptococcus pneumoniae type 14 (SP14) capsular polysaccharide are presented. By exploiting a block strategy, the negative charge has been installed on the non-reducing end of the lactose unit of the tetrasaccharide and the positive charge either on the non-reducing end of the lactosamine moiety or on an external linker. These structures have then been tested by competitive ELISA, showing that the structural variations we made do not modify the affinity of the neutral compound to binding to a specific antibody. However, lower efficacies than the natural SP14 compound were observed. The results obtained, although promising, point to the need to further elongate the polysaccharide structure, which is likely too short to cover the entire epitopes.

scholarly journals Serum immunoglobulins and anti-pneumococcal antibody levels in patients with bronchiectasis of unknown aetiology

2020 ◽  
Vol 19 (2) ◽  
pp. 200-207
Author(s):  
Mustafa Norhazlin ◽  
Asrul Abdul Wahab ◽  
Mohd Faisal Abdul Hamid ◽  
Hamzaini Abdul Hamid ◽  
Husyairi Harunarashid
Keyword(s):  
Streptococcus Pneumoniae ◽  
Specific Antibody ◽  
Capsular Polysaccharide ◽  
Medical Science ◽  
Asian Population ◽  
Immunoglobulin Therapy ◽  
Female Gender ◽  
Total Serum ◽  
Capsular Polysaccharides ◽  
Serum Immunoglobulins

Background: Bronchiectasis is a chronic condition which can result in significant physical and social morbidity. The exact prevalence in Malaysia is unknown although several studies have shown a higher prevalence in the Asian population. Several causative factors have been identified but there are many patients with unknown aetiologies. This study looks into the level of serum immunoglobulins and antipenumococcal antibody in bronchiectasis patients where they were not part of prior routine investigations. Methodology: Four hundred fifteen bronchiectasis patients were screened and 26 patients who fulfilled the inclusion and exclusion criteria were enrolled for this study. The serum immunoglobulins (IgG, IgA and IgM) concentrations were measured using nephelometry and interpreted according to age-matched reference range. The integrity of antibody production against specific antibody to capsular polysaccharides of Streptococcus pneumoniae were assessed using ELISA method and the level of ≥ 10mg/L is considered as reactive. Results: The twenty six bronchiectasis patients have the mean age of 62 years and a predilection of female gender. Majority of patients presented with typical bronchiectasis symptoms which were further supported by radiological findings. One of 26 patients (4%) had low total serum IgG level. The vaccinated group has higher anti-pneumococcal capsular polysaccharide antibody level (median: 224.2 mg/L) compared to the unvaccinated group (median: 100.4 mg/L). However there is no statistical difference between the anti-PCP levels of both groups (p> 0.05). All of the selected patients had reactive specific antibody to capsular polysaccharides of Streptococcus pneumoniae regardless of the vaccination status, which may reflect the natural acquisition of anti-pneumococcal immunity. Conclusion: Although immunoglobulin deficiency is an uncommon aetiological cause of bronchiectasis, the immunoglobulin parameters can be helpful in selecting patients who should receive the appropriate treatment of immunoglobulin therapy for the prevention of subsequent complications and better quality of life. Bangladesh Journal of Medical Science Vol.19(2) 2020 p.200-207

scholarly journals Identification of the Smallest Structure Capable of Evoking Opsonophagocytic Antibodies against Streptococcus pneumoniae Type 14

2008 ◽  
Vol 76 (10) ◽  
pp. 4615-4623 ◽  
Author(s):  
Dodi Safari ◽  
Huberta A. T. Dekker ◽  
John A. F. Joosten ◽  
Dirk Michalik ◽  
Adriana Carvalho de Souza ◽  
...  
Keyword(s):  
Streptococcus Pneumoniae ◽  
Antibody Response ◽  
Conjugate Vaccine ◽  
Specific Antibody ◽  
Capsular Polysaccharide ◽  
Specific Antibody Response ◽  
Specific Antibodies

ABSTRACT Synthetic overlapping oligosaccharide fragments of Streptococcus pneumoniae serotype 14 capsular polysaccharide (Pn14PS), {6)-[β-d-Galp-(1→4)-]β-d-GlcpNAc-(1→3)-β-d-Galp-(1→4)-β-d-Glcp-(1→}n, were conjugated to CRM197 protein and injected into mice to determine the smallest immunogenic structure. The resulting antibodies were then tested for Pn14PS specificity and for their capacity to promote the phagocytosis of S. pneumoniae type 14 bacteria. Earlier studies have reported that the oligosaccharide corresponding to one structural repeating unit of Pn14PS, i.e., Gal-Glc-(Gal-)GlcNAc, induces a specific antibody response to Pn14PS. The broader study described here, which evaluated 16 oligosaccharides, showed that the branched trisaccharide element Glc-(Gal-)GlcNAc is essential in inducing Pn14PS-specific antibodies and that the neighboring galactose unit at the nonreducing end contributes clearly to the immunogenicity of the epitope. Only the oligosaccharide conjugates that produce antibodies recognizing Pn14PS were capable of promoting the phagocytosis of S. pneumoniae type 14. In conclusion, the branched tetrasaccharide Gal-Glc-(Gal-)GlcNAc may be a serious candidate for a synthetic oligosaccharide conjugate vaccine against infections caused by S. pneumoniae type 14.

scholarly journals Automated glycan assembly of Streptococcus pneumoniae type 14 capsular polysaccharide fragments

RSC Advances ◽  
2020 ◽  
Vol 10 (40) ◽  
pp. 23668-23674 ◽  
Author(s):  
João Louçano ◽  
Peter Both ◽  
Andrea Marchesi ◽  
Linda del Bino ◽  
Roberto Adamo ◽  
...  
Keyword(s):  
Streptococcus Pneumoniae ◽  
Capsular Polysaccharide ◽  
Building Blocks ◽  
Competitive Elisa ◽  
Automated Synthesis ◽  
Type Iii ◽  
Group B ◽  
Insight Into

A streamlined automated synthesis for S. pneumoniae type 14 and Group B Streptococcus type III capsular oligosaccharides with only one set of three building blocks is presented. Competitive ELISA provides some insight into minimal epitope.

scholarly journals Zerumbone Inhibits Helicobacter pylori Urease Activity

Molecules ◽  
2021 ◽  
Vol 26 (9) ◽  
pp. 2663
Author(s):  
Hyun Jun Woo ◽  
Ji Yeong Yang ◽  
Pyeongjae Lee ◽  
Jong-Bae Kim ◽  
Sa-Hyun Kim
Keyword(s):  
Helicobacter Pylori ◽  
Carbon Atom ◽  
Natural Compound ◽  
Urease Activity ◽  
Negative Charge ◽  
Positive Charge ◽  
Gastric Epithelium ◽  
Functional Inhibition ◽  
Electrical Gradient ◽  
H Pylori

Helicobacter pylori (H. pylori) produces urease in order to improve its settlement and growth in the human gastric epithelium. Urease inhibitors likely represent potentially powerful therapeutics for treating H. pylori; however, their instability and toxicity have proven problematic in human clinical trials. In this study, we investigate the ability of a natural compound extracted from Zingiber zerumbet Smith, zerumbone, to inhibit the urease activity of H. pylori by formation of urease dimers, trimers, or tetramers. As an oxygen atom possesses stronger electronegativity than the first carbon atom bonded to it, in the zerumbone structure, the neighboring second carbon atom shows a relatively negative charge (δ−) and the next carbon atom shows a positive charge (δ+), sequentially. Due to this electrical gradient, it is possible that H. pylori urease with its negative charges (such as thiol radicals) might bind to the β-position carbon of zerumbone. Our results show that zerumbone dimerized, trimerized, or tetramerized with both H. pylori urease A and urease B molecules, and that this formation of complex inhibited H. pylori urease activity. Although zerumbone did not affect either gene transcription or the protein expression of urease A and urease B, our study demonstrated that zerumbone could effectively dimerize with both urease molecules and caused significant functional inhibition of urease activity. In short, our findings suggest that zerumbone may be an effective H. pylori urease inhibitor that may be suitable for therapeutic use in humans.

scholarly journals Antibodies to Streptococcus pneumoniae Capsular Polysaccharide Enhance Pneumococcal Quorum Sensing

mBio ◽  
2011 ◽  
Vol 2 (5) ◽  
Author(s):  
Masahide Yano ◽  
Shruti Gohil ◽  
J. Robert Coleman ◽  
Catherine Manix ◽  
Liise-anne Pirofski
Keyword(s):  
Monoclonal Antibodies ◽  
Streptococcus Pneumoniae ◽  
Quorum Sensing ◽  
Direct Effect ◽  
Pneumococcal Disease ◽  
Effector Cell ◽  
Capsular Polysaccharide ◽  
Genetic Exchange ◽  
Content Type ◽  
Specific Antibodies

ABSTRACTThe use of pneumococcal capsular polysaccharide (PPS)-based vaccines has resulted in a substantial reduction in invasive pneumococcal disease. However, much remains to be learned about vaccine-mediated immunity, as seven-valent PPS-protein conjugate vaccine use in children has been associated with nonvaccine serotype replacement and 23-valent vaccine use in adults has not prevented pneumococcal pneumonia. In this report, we demonstrate that certain PPS-specific monoclonal antibodies (MAbs) enhance the transformation frequency of two differentStreptococcus pneumoniaeserotypes. This phenomenon was mediated by PPS-specific MAbs that agglutinate but do not promote opsonic effector cell killing of the homologous serotypeinvitro. Compared to the autoinducer, competence-stimulating peptide (CSP) alone, transcriptional profiling of pneumococcal gene expression after incubation with CSP and one such MAb to the PPS of serotype 3 revealed changes in the expression of competence (com)-related and bacteriocin-like peptide (blp) genes involved in pneumococcal quorum sensing. This MAb was also found to induce a nearly 2-fold increase in CSP2-mediated bacterial killing or fratricide. These observations reveal a novel, direct effect of PPS-binding MAbs on pneumococcal biology that has important implications for antibody immunity to pneumococcus in the pneumococcal vaccine era. Taken together, our data suggest heretofore unsuspected mechanisms by which PPS-specific antibodies could affect genetic exchange and bacterial viability in the absence of host cells.IMPORTANCECurrent thought holds that pneumococcal capsular polysaccharide (PPS)-binding antibodies protect against pneumococcus by inducing effector cell opsonic killing of the homologous serotype. While such antibodies are an important part of how pneumococcal vaccines protect against pneumococcal disease, PPS-specific antibodies that do not exhibit this activity but are highly protective against pneumococcus in mice have been identified. This article examines the effect of nonopsonic PPS-specific monoclonal antibodies (MAbs) on the biology ofStreptococcus pneumoniae. The results showed that in the presence of a competence-stimulating peptide (CSP), such MAbs increase the frequency of pneumococcal transformation. Further studies with one such MAb showed that it altered the expression of genes involved in quorum sensing and increased competence-induced killing or fratricide. These findings reveal a novel, previously unsuspected mechanism by which certain PPS-specific antibodies exert a direct effect on pneumococcal biology that has broad implications for bacterial clearance, genetic exchange, and antibody immunity to pneumococcus.

Structural studies of the capsular polysaccharide from Streptococcus pneumoniae Type 12F

1981 ◽  
Vol 59 (14) ◽  
pp. 2081-2085 ◽  
Author(s):  
Karin Leontein ◽  
Bengt Lindberg ◽  
Jörgen Lönngren
Keyword(s):  
Streptococcus Pneumoniae ◽  
Nmr Spectroscopy ◽  
Capsular Polysaccharide ◽  
Structural Studies ◽  
Methylation Analysis ◽  
Mannuronic Acid ◽  
Structure Formula

The capsular polysaccharide from Streptococcus pneumoniae type 12F is composed of D-glucosyl, D-galactosyl, 2-acetamido-2-deoxy-D-galactosyl, 2-acetamido-2,6-dideoxy-L-galactosyl, and 2-acetamido-2-deoxy-D-mannuronic acid residues in the proportions 2:1:1:1:1. The main structural evidence was adduced from nmr spectroscopy, methylation analysis, and specific degradations whereby it could be concluded that the polysaccharide is composed of hexasaccharide repeating-units having the structure:[Formula: see text]

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