scholarly journals Immunobiological Properties of Antigenic Preparations Streptococcus pneumoniae and their Mixtures

2022 ◽  
Vol 20 (6) ◽  
pp. 5-11
Author(s):  
M. M. Tokarskaya ◽  
E. A. Nayаnova ◽  
O. V. Nechaeva ◽  
S. A. Baranovskaya ◽  
O. M. Afanacyeva ◽  
...  

Relevance. Type-specific immunity does not protect against infection with other pneumococcal serotypes. The phenomenon of the change of serotypes dominating the population of Streptococcus pneumoniae is known, in part due to the intensive recombination process and the phenomenon of «capsule switching». Therefore, the development of a serotype-independent pneumococcal vaccine is an important global public health priority. Ams. Investigation of immunobiological properties of candidate components of a future vaccine with serotype-independent activity. Materials and methods. For immunization of mice, preparations of the capsular polysaccharide of pneumococcus serotype 3 (CPS) were used; protein-containing fraction (PCF) obtained from an aqueous extract of S. pneumoniae 6B cells; recombinant pneumolysin (Ply); mixtures of drugs (CPS + Plу; CPS + PCF; PCF + Plу); conjugate vaccine Prevnar 13 (manufactured by PFIZER Inc. USA). Mice were immunized intraperitoneally, 2 times with an interval of 14 days. Intact mice were used as a control group. To assess the humoral immune IgG response, the method of solid-phase ELISA was used. Phagocytic activity was studied at 7, 14, 21 and 28 days after the second immunization. The cytokine level was determined in the blood sera of mice after the second immunization 2, 4, 8, and 24 hours later on a NovoCyte flow cytometer (ACEA Biosciences, USA) using the MACSPIex CytoKine 10 Kit mouse (Miltenyi Biotec Inc., USA) according to the manufacturer's instructions. Results. Immunization of mice with Ply as well as mixtures with CPS and PCF caused a significant increase in the level of antibodies to Ply. It was found that there was no apparent decrease in the level of antigen-specific antibodies when antigens were administered in combination with others. Pneumolysin, used alone or in combination with PCF and CPS, induces the production of antiinflammatory cytokines IL-4, IL-10, and IL-5 detected throughout the study. This is confirmed by a study of the opsonophagocytic activity of neutrophils from immunized CPS + Ply, Ply + PCF and Ply mice; a significant increase in the number of eosinophils is observed in their blood due to the stimulation of their production of IL-5. Conclusions. As a result of the studies, it was shown that Ply, used alone or in combination with CPS and PCF, has the highest immunogenicity: it stimulates a significant increase in the level of specific antibodies, stimulates Th-2, and induces the production of anti-inflammatory cytokines.

mBio ◽  
2011 ◽  
Vol 2 (5) ◽  
Author(s):  
Masahide Yano ◽  
Shruti Gohil ◽  
J. Robert Coleman ◽  
Catherine Manix ◽  
Liise-anne Pirofski

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.


Author(s):  
I. V. Yakovleva ◽  
E. A. Kurbatova ◽  
E. A. Akhmatova ◽  
E. V. Sukhova ◽  
D. V. Yashunsky ◽  
...  

Aim. Production of monoclonal antibodies (mAb) to synthetic tetrasaccharide - repeating unit of the capsular polysaccharide (CP) of Streptococcus pneumoniae serotype 14 and their immunochemical characterization. Materials and methods. In order to generate the hybridoma producing mAb, mice were immunized with synthetic tetrasaccharide conjugated with bovine serum albumin (BSA) with following hybridization of B lymphocytes with mouse myeloma cells. Antibodies were obtained in vitro andin vivo. Immunochemical characterization of mAb to tetrasaccharide was carried out using a variety of ELISA options. Results. For the first time obtained mouse hybridoma, producing IgM to tetrasacchride. The IgM titer of anti-tetrasacharide antibodies in supernatants of clones and in the ascitic fluid of mice in ELISA detected by biotinylated tetrasaccharide and synthetic CP adsorbed on the solid phase was higher compared to the use of bacterial CP as well cover antigen. In the reaction of inhibition of the ELISA, the mAb recognized the corresponding carbohydrate epitopes of the bacterial CP of S. pneumoniae serotype 14 dissolved in the liquid phase better than tetrasaccharide ligand and synthetic CP. Conclusion. To detect mAb to tetrasaccharide in ELISA preferably to use synthetic analogues of the CP as solid phase antigens. The obtained mAb to tetrasaccharide can be used to determine the representation of the protective tetrasaccharide epitope of CP in the development of pneumococcal vaccines.


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 ◽  
...  

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.


1988 ◽  
Vol 106 (1) ◽  
pp. 101-107 ◽  
Author(s):  
Guy J.W.J. Zigterman ◽  
AndréF.M. Verheul ◽  
Erna B.H.W. Ernste ◽  
Ronald F.M. Rombouts ◽  
Marinus J. De Reuver ◽  
...  

2008 ◽  
Vol 77 (2) ◽  
pp. 676-684 ◽  
Author(s):  
Merit Melin ◽  
Hanna Jarva ◽  
Lotta Siira ◽  
Seppo Meri ◽  
Helena Käyhty ◽  
...  

ABSTRACT The polysaccharide capsule is a major virulence mechanism of Streptococcus pneumoniae, shielding the bacterium from phagocytes. Capsule types may differ in their abilities to resist immune defense. Antibody-mediated complement activation and opsonophagocytosis are crucial in protection against pneumococcus. Conjugate vaccine trials suggest imperfect protection against 19F. We have previously shown that significantly more anti-19F than anti-6B antibody is needed for killing in the opsonophagocytic assay (OPA). In this study, we explored whether the amount of C3 deposited on serotype 6B and 19F pneumococcal strains reflects their sensitivity to opsonophagocytosis. We compared clinical 6B and 19F nasopharyngeal, middle ear, and blood isolates as well as reference OPA strains (n = 16) for their sensitivity to opsonophagocytosis and C3 deposition. Sixfold anticapsular antibody concentrations were required for 50% opsonophagocytic killing of 19F compared to that of 6B strains. Serotype 19F was more resistant to C3 deposition than 6B. Complement deposition and opsonophagocytosis were dependent on the concentration of anticapsular antibodies. Differences between pneumococcal serotypes in antibody-mediated protection may partly be explained by the abilities of the capsules to resist complement deposition. These findings support previous studies suggesting that higher antibody concentrations to the capsular polysaccharide are needed for protection against disease caused by serotype 19F than that caused by 6B.


2000 ◽  
Vol 7 (3) ◽  
pp. 486-489 ◽  
Author(s):  
M. K. Park ◽  
D. E. Briles ◽  
M. H. Nahm

ABSTRACT A simple and rapid method of simultaneously determining 15Streptococcus pneumoniae serotypes was developed. Fifteen latex beads of different sizes and different red fluorescence levels were coated with 1 of 15 serotypes (1, 3, 4, 5, 6A, 6B, 7F, 9N, 9V, 14, 18C, 19A, 19F, 22F, and 23F) of pneumococcal capsular polysaccharide (PS). The bead mixture was incubated with individual pneumococcal lysate, a pool of rabbit antisera capable of binding the 15 serotypes, and fluorescein (green fluorescence)-conjugated anti-rabbit antibody. Bead size, red fluorescence, and green fluorescence were measured in a single flow cytometer run. The green fluorescence of the beads was inhibited only when there was a serotypic match between PS on the bead and PS in the pneumococcal lysate. This method distinguished cross-reactive serotypes and correctly identified the serotypes in 100% of 86 pneumococcal isolates tested.


2009 ◽  
Vol 16 (9) ◽  
pp. 1279-1284 ◽  
Author(s):  
Hans-Christian Slotved ◽  
Christina Guttmann ◽  
Charlotte Demuth Pedersen ◽  
Jasper Neergaard Jacobsen ◽  
Karen Angeliki Krogfelt

ABSTRACT Worldwide, Streptococcus pneumoniae (pneumococcus) is a major cause of morbidity and mortality, especially in infants and elderly people. Pneumococcal capsular polysaccharides are well characterized, and more than 90 different serotypes have been identified. Serotype-specific antibodies against the capsular polysaccharide are produced during infection. Detection of antibodies against pneumococci by enzyme-linked immunosorbent assay (ELISA) is performed according to WHO guidelines, using antigens provided by ATCC. However, testing the ELISA for specificity is challenging due to the difficulty in obtaining human naïve serum with pneumococcal antibodies as well as human serum with antibodies against a single serotype. The application of well-defined serotype-specific sera produced in animals to evaluate the specificity of the ATCC antigens and the effect of adsorption with cell wall and 22F polysaccharides has not been performed before, to our knowledge. In this study, the specificity of ATCC antigens (serotypes 4, 6B, 9V, 14, 18C, 19F, and 23F) was tested by using commercial serotype-, serogroup-, and pool-specific pneumococcal rabbit antisera.


Vaccine ◽  
2010 ◽  
Vol 28 (47) ◽  
pp. 7542-7550 ◽  
Author(s):  
Kevin Fabrizio ◽  
Catherine Manix ◽  
Haijun Tian ◽  
Nico van Rooijen ◽  
Liise-anne Pirofski

2000 ◽  
Vol 30 (3) ◽  
pp. 449-453 ◽  
Author(s):  
Celso Guimarães Barbosa ◽  
Argemiro Sanavria ◽  
Ronald Bastos Freire

Six bovines were infested with 60 first instar larvae of Dermatobia hominis. The animals were bleed weekly, and their antibodies levels to D. hominis L1, L2 and L3 instars measured during the time, following the infestation course. The antisera were submitted to a titration against optimal dilutions of antigen coated wells of microplates, previously sensitized with L1, L2 and L3 preparations, respectively. The ELISA assay was used to test single dilutions of antisera, which results were comparatively analyzed with a control of not infested animals. Antibodies against L1 were detected between the first and 21st day post-infestation (DPI) and, from the 42nd DPI on. Anti-L2 antibodies, could be detected on the 21st DPI and from the 35th DPI until approximately the 49th DPI, when it was observed a decreasing of antibodies titration equivalent to the control group. No antibodies were detected against the L3 instar-antigens. Antibodies levels against L1 showed absorbance higher than 1.500 O.D. at 492nm in the ELISA assay, when compared to the 0.096 O.D. observed to the negative animals. High anti-L2 antibodies were also detected on the 21st DPI, where two animals showed O.D. of 0.450 and 0.900 at 492nm, with a cut-off estimated on 0.110 O.D. It was also demonstrated a rising of anti-L2 antibodies in the same four animals, which presented antibodies response against L1 instar. The obtained results, with an estimated prevalence of 50%, were comparatively evaluated, taking the double diffusion immunoassay precipitation test as a standard, and showed a concordance of 98%. The association between infestation and presence of specific antibodies was also discussed.


2021 ◽  
Vol 11 (5) ◽  
pp. 934-942
Author(s):  
I. D. Reshetnikova ◽  
Yu. A. Tyurin ◽  
E. V. Agafonova ◽  
S. N. Kulikov ◽  
G. F. Gilyazutdinova ◽  
...  

Relevance. Since the beginning of the epidemic in China, there have been reports of nosocomial cases of SARSCoV-2 infection, including among medical workers. Studies of the intensity of humoral immune response to the SARSCoV-2 virus among medical workers who are much more likely to have professional contact with COVID-19 patients than are of particular importance. The aim is to study the seroprevalence and features of the humoral immune response to SARS-CoV-2 among medical workers. Materials and methods. The study included 61 medical workers from a multidisciplinary hospital in Kazan, which was redesigned to provide medical care to patients with new coronavirus infection, using the method of random sampling. The control group consisted of 60 non-medical workers. For the determination of IgG, a solid-phase ELISA was used. Statistical processing of the results was carried out using MS Excel software. The error of the relative value (M±m) was calculated, and the 95% confidence interval of the frequency of occurrence. To assess the significance of differences, the Student’s test (t-test) was used for independent samples. Results. The proportion of those seropositive to SARS-CoV-2 in the study group was 45.9%, compared with 21.7% in the control group. Among medical workers seropositive to the SARS-CoV-2 virus, the proportion of asymptomatic forms was 18.5%, mild forms — 53.6%, moderate forms and severe forms 25%. Two forms of the formation of a humoral immune response among seropositive ones were revealed: the first is characterized by the gradual elimination of specific IgG antibodies to SARSCoV-2 after 8 weeks from the onset of the first symptoms of COVID-19, the second form is an increase in specific IgG to SARS-CoV-2 and a higher value of the coefficient level of IgM positivity to SARS-CoV-2 after 8–10 weeks from the onset of the first symptoms. The group of seropositive, “raising antibodies”, prevailed over the group of individuals “eliminating antibodies”. Among seropositive medical workers, two forms of the formation of a humoral immune response were revealed: synchronous with the parallel elimination of IgG and IgM antibodies and a parallel increase in IgG and IgM. Conclusion. The study of the level of humoral immunity to COVID-19 in medical workers is important in terms of planning both anti-epidemic measures and predicting the effectiveness of the response to vaccination to SARS-CoV-2.


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