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PROVIDER: PRJNA1137437 | ENA |
REPOSITORIES: ENA
Similar Datasets
Project description:Genetic diversification within pneumococcal biofilms
| PRJNA314121 | ENA
Project description:The primary mechanism by which pneumococcal capsular polysaccharide-based vaccines are believed to mediate protection is by induction of serotype-specific opsonic antibodies that facilitate bacterial killing by phagocytes (opsonophagocytosis). However, antibodies that are protective against experimental pneumococcal pneumonia in mice but do not promote opsonophagocytic killing in vitro have also been identified 1-3. Such non-opsonic antibodies are associated with bacterial clearance in vivo, but the mechanism by which this occurs is unknown. In this letter, we demonstrate that a protective, non-opsonic serotype 3 pneumococcal capsular polysaccharide-specific monoclonal antibody (MAb) enhances quorum sensing, which results in competence induction and fratricide of serotype 3 pneumococcus. Gene expression profile analysis revealed that the MAb together with the pneumococcal autoinducer, competence stimulating peptide 2 (CSP2), augments differential expression of competence (com) related bacteriocin-like peptide (blp) genes that are known to be involved in pneumococcal fratricide. Taken together, these findings reveal a previously unsuspected mechanism of antibody action, namely, enhancement of quorum sensing and bacterial fratricide. Given that this activity does not require phagocytes, antibodies that function accordingly may hold promise as adjuncts to current vaccines or as desired products of next generation pneumococcal vaccines.
2011-03-01 | GSE27258 | GEO
Project description:The objective of this study is to: 1) Characterize the immune responsiveness to administration of non-live vaccines in three cohorts of healthy adult subjects through the analysis of blood leukocytes transcriptional profiles. 2) Validate whole blood transcriptional profiles generated from standard 3mL blood draws versus 200uL blood draws obtained by finger stick. 3) Discover potential biomarkers for immune-responsiveness to non-live vaccines. A total of 621 blood samples were collected either by venipuncture (387) or finger prick (234) from four groups of healthy adults receiving either, 2009/10 seasonal influenza or 23-valent pneumococcal vaccine or placebo (saline) injections. Subjects were recruited in 3 cohorts with 4-7 individuals per group; cohort 3 was recruited for validation of the systemic day 1 immune signature in response to seasonal influenza and pneumococcal vaccination. From each subject, peripheral blood was drawn into Tempus tubes (Applied Biosystems) or obtained by finger prick into micro capillaries and then transferred into tempus reagent to lyse blood cells and stabilize RNA before storing at -80ºC until mRNA extraction. The training set for transcriptional profiling of blood obtained by venipuncture was performed in cohort 1 which included 6 healthy adult individuals receiving seasonal influenza vaccine, 6 healthy adult individuals receiving pneumococcal vaccine, and 6 healthy adult individuals receiving placebo (saline injections). The test set for transcriptional profiling of blood obtained by venipuncture was performed in cohort 2 which included 6 healthy adult individuals receiving seasonal influenza vaccine, 6 healthy adult individuals receiving pneumococcal vaccine, and 6 healthy adult individuals receiving placebo (saline injections). The validation set for confirming systemic day 1 transcriptome immune signature in response to seasonal influenza and pneumococcal vaccination was performed in cohort 3 which included 6 healthy adult individuals receiving seasonal influenza vaccine and 4 healthy adult individuals receiving pneumococcal vaccine. The training set for transcriptional profiling of blood obtained by finger prick was performed in cohort 2 and the test set in cohort 1.
2013-04-19 | E-GEOD-30101 | biostudies-arrayexpress
Project description:The objective of this study is to: 1) Characterize the immune responsiveness to administration of non-live vaccines in three cohorts of healthy adult subjects through the analysis of blood leukocytes transcriptional profiles. 2) Validate whole blood transcriptional profiles generated from standard 3mL blood draws versus 200uL blood draws obtained by finger stick. 3) Discover potential biomarkers for immune-responsiveness to non-live vaccines. A total of 621 blood samples were collected either by venipuncture (387) or finger prick (234) from four groups of healthy adults receiving either, 2009/10 seasonal influenza or 23-valent pneumococcal vaccine or placebo (saline) injections. Subjects were recruited in 3 cohorts with 4-7 individuals per group; cohort 3 was recruited for validation of the systemic day 1 immune signature in response to seasonal influenza and pneumococcal vaccination. From each subject, peripheral blood was drawn into Tempus tubes (Applied Biosystems) or obtained by finger prick into micro capillaries and then transferred into tempus reagent to lyse blood cells and stabilize RNA before storing at -80ºC until mRNA extraction. The training set for transcriptional profiling of blood obtained by venipuncture was performed in cohort 1 which included 6 healthy adult individuals receiving seasonal influenza vaccine, 6 healthy adult individuals receiving pneumococcal vaccine, and 6 healthy adult individuals receiving placebo (saline injections). The test set for transcriptional profiling of blood obtained by venipuncture was performed in cohort 2 which included 6 healthy adult individuals receiving seasonal influenza vaccine, 6 healthy adult individuals receiving pneumococcal vaccine, and 6 healthy adult individuals receiving placebo (saline injections). The validation set for confirming systemic day 1 transcriptome immune signature in response to seasonal influenza and pneumococcal vaccination was performed in cohort 3 which included 6 healthy adult individuals receiving seasonal influenza vaccine and 4 healthy adult individuals receiving pneumococcal vaccine. The training set for transcriptional profiling of blood obtained by finger prick was performed in cohort 2 and the test set in cohort 1.
2013-07-10 | E-GEOD-48762 | biostudies-arrayexpress
Project description:Understanding the genetic diversification within pneumococcal biofilms.
| PRJNA259232 | ENA
Project description:The primary mechanism by which pneumococcal capsular polysaccharide-based vaccines are believed to mediate protection is by induction of serotype-specific opsonic antibodies that facilitate bacterial killing by phagocytes (opsonophagocytosis). However, antibodies that are protective against experimental pneumococcal pneumonia in mice but do not promote opsonophagocytic killing in vitro have also been identified 1-3. Such non-opsonic antibodies are associated with bacterial clearance in vivo, but the mechanism by which this occurs is unknown. In this letter, we demonstrate that a protective, non-opsonic serotype 3 pneumococcal capsular polysaccharide-specific monoclonal antibody (MAb) enhances quorum sensing, which results in competence induction and fratricide of serotype 3 pneumococcus. Gene expression profile analysis revealed that the MAb together with the pneumococcal autoinducer, competence stimulating peptide 2 (CSP2), augments differential expression of competence (com) related bacteriocin-like peptide (blp) genes that are known to be involved in pneumococcal fratricide. Taken together, these findings reveal a previously unsuspected mechanism of antibody action, namely, enhancement of quorum sensing and bacterial fratricide. Given that this activity does not require phagocytes, antibodies that function accordingly may hold promise as adjuncts to current vaccines or as desired products of next generation pneumococcal vaccines. 6 samples
2011-03-01 | E-GEOD-27258 | biostudies-arrayexpress
Project description:Streptococcus pneumoniae is a frequent coloniser of the human nasopharynx and a major cause of life-threating invasive infections such as pneumonia, meningitis and sepsis. Over 1 million people die every year due to invasive pneumococcal disease (IPD), mainly in developing countries. Serotype 1 is a common cause of IPD; however, unlike other serotypes, it is rarely found in the carrier state in the nasopharynx, which is often considered a prerequisite for disease. The aim of this study was to understand this dichotomy. We used murine models of carriage and IPD to characterise the pathogenesis of African serotype 1 (Sequence Type 217) pneumococcal strains obtained from the Queen Elizabeth Central Hospital in Blantyre, Malawi. We found that ST217 pneumococcal strains were highly virulent in a mouse model of invasive pneumonia, but in contrast to the generally accepted assumption, can also successfully establish nasopharyngeal carriage. Interestingly, we found that co-colonising serotypes may proliferate in the presence of serotype 1, suggesting that acquisition of serotype 1 carriage could increase the risk of developing IPD by other serotypes. RNAseq analysis confirmed that key virulence genes associated with inflammation and tissue invasiveness were upregulated in serotype 1. These data reveal important new insights into serotype 1 pathogenesis, with implications for carriage potential and risk of invasive disease through interactions with other co-colonising serotypes; an often overlooked factor in transmission and disease progression.
2020-11-12 | GSE159305 | GEO
Project description:Infection of the human host by Streptococcus pneumoniae begins with colonization of the nasopharynx, which is mediated by adherence of bacteria to respiratory epithelium. Several studies have indicated an important role for the pneumococcal capsule in this process. Here, we used microarrays to characterize the in vitro transcriptional response of human nasopharyngeal epithelial Detroit 562 cells to adherence of serotype 2-encapsulated strain D39, serotype 19F-encapsulated strain G54, serotype 4-encapsulated strain TIGR4, and their nonencapsulated derivatives (delta-cps). In total, 322 genes were found to be upregulated in response to adherent pneumococci. Twenty-two genes were commonly induced, including those encoding several cytokines (e.g., IL-1-beta, IL-6), chemokines (e.g., IL-8, CXCL1/2), and transcriptional regulators (e.g., FOS), consistent with an innate immune response mediated by Toll-like receptor signaling. Interestingly, 85% of genes was induced specifically by one or more encapsulated strains, suggestive of a capsule-dependent response. Importantly, purified capsular polysaccharides alone had no effect. Over a third of these loci encoded products predicted to be involved in transcriptional regulation and signal transduction, in particular MAPK signaling pathways. Real-time PCR of a subset of ten genes confirmed microarray data and showed a time-dependent upregulation of especially innate immunity genes. Downregulation of epithelial genes was most pronounced upon adherent D39delta-cps, as 68% of the 161 genes identified was only repressed using this nonencapsulated strain. In conclusion, we identified a subset of host genes specifically induced by encapsulated strains during in vitro adherence, and have demonstrated the complexity of interactions occurring during the initial stages of pneumococcal infection. Experiment Overall Design: We used three different pneumococcal strains and their isogenic nonencapsulated derivatives (delta-cps): serotype 2-encapsulated strain D39, serotype 19F-encapsulated strain G54, and serotype 4-encapsulated strain TIGR4. All experiments were performed in triplicate (3 independent biological replicates) and compared to uninfected control Detroit 562 cells. Bacteria were allowed to adhere to the epithelial cells for 2 hours, after which the transcriptional response of the Detroit cells was analyzed using Affymetrix Human U133 Plus GeneChips. In addition to the 6 strains mentioned above, we included transcriptional analysis of the epithelial cell response to low-dose D39delta-cps (giving adherence equivalent to wild-type D39) and purified type 2 capsular polysaccharides.
2008-06-16 | E-GEOD-8527 | biostudies-arrayexpress
Project description:With annually 2.56 million deaths worldwide, pneumonia is one of the leading causes of death. Most frequent causative pathogens are Streptococcus pneumoniae and influenza A virus. Lately, the interaction between pathogens, the host and its microbiome gained more attention. A healthy microbiome is known to enhance the immune response towards pathogens, however, our knowledge on how infections affect the microbiome is still scarce. In this study, a meta-omics approach was used to investigate the impact of S. pneumoniae and influenza A virus infection on structure and function of the respiratory and gastrointestinal microbiomes of mice. In particular, the taxonomic composition of the respiratory microbiome was less affected by bacterial colonization and viral infection compared to S. pneumoniae infection. Pneumococcal pneumonia led to reduction of bacterial families and lower diversity in the respiratory microbiome, whereas diversity/richness was unaffected following H1N1 infection. Within the gastrointestinal microbiome we found exclusive changes in structure and function depending on the pneumonia inducing pathogen. Exemplarily, increased abundance of Akkermansiaceae and Spirochaetaceae, as well as decreased amounts of Clostridiaceae in response to S. pneumoniae infection, while increased presence of Enterococcaceae and Staphylococcaceae was specific for viral-induced pneumonia. Investigation of the intestinal microbiomes functional composition revealed reduced expression of flagellin and rubrerythrin and increased levels of ATPase during pneumococcal infection, while increased amounts of acetyl-CoA acetyltransferase and, enoyl-CoA transferase were unique after H1N1 infection. The identification of specific taxonomical and functional profiles during infection with a respective pathogen could deliver new insights in the role of the microbiome during disease and be beneficial for discrimination of pneumococcal- or viral-induced pneumonia.
2023-03-24 | PXD036115 | Pride
Project description:With annually 2.56 million deaths worldwide, pneumonia is one of the leading causes of death. Most frequent causative pathogens are Streptococcus pneumoniae and influenza A virus. Lately, the interaction between pathogens, the host and its microbiome gained more attention. A healthy microbiome is known to enhance the immune response towards pathogens, however, our knowledge on how infections affect the microbiome is still scarce. In this study, a meta-omics approach was used to investigate the impact of S. pneumoniae and influenza A virus infection on structure and function of the respiratory and gastrointestinal microbiomes of mice. In particular, the taxonomic composition of the respiratory microbiome was less affected by bacterial colonization and viral infection compared to S. pneumoniae infection. Pneumococcal pneumonia led to reduction of bacterial families and lower diversity in the respiratory microbiome, whereas diversity/richness was unaffected following H1N1 infection. Within the gastrointestinal microbiome we found exclusive changes in structure and function depending on the pneumonia inducing pathogen. Exemplarily, increased abundance of Akkermansiaceae and Spirochaetaceae, as well as decreased amounts of Clostridiaceae in response to S. pneumoniae infection, while increased presence of Enterococcaceae and Staphylococcaceae was specific for viral-induced pneumonia. Investigation of the intestinal microbiomes functional composition revealed reduced expression of flagellin and rubrerythrin and increased levels of ATPase during pneumococcal infection, while increased amounts of acetyl-CoA acetyltransferase and, enoyl-CoA transferase were unique after H1N1 infection. The identification of specific taxonomical and functional profiles during infection with a respective pathogen could deliver new insights in the role of the microbiome during disease and be beneficial for discrimination of pneumococcal- or viral-induced pneumonia.
2023-03-24 | PXD036014 | Pride