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Medical Microbiology and Immunology Dec 2021The aim of this study was to compare the elimination of Bordetella pertussis clinical isolates, representing different genotypes in relation to alleles encoding...
The aim of this study was to compare the elimination of Bordetella pertussis clinical isolates, representing different genotypes in relation to alleles encoding virulence factors (MLST-multi-locus antigen sequence typing), MLVA type (multi-locus variable-number tandem repeat analysis) and PFGE group (pulsed-field gel electrophoresis) from the lungs of naive mice or mice were immunised with the commercial whole-cell pertussis vaccine, the acellular pertussis vaccine and the experimental whole-cell pertussis vaccine. Molecular data indicate that the resurgence of pertussis in populations with high vaccine coverage is associated with genomic adaptation of B. pertussis, to vaccine selection pressure. Pertactin-negative B. pertussis isolates were suspected to contribute to the reduced vaccine effectiveness. It was shown that one of the isolates used is PRN deficient. The mice were intranasally challenged with bacterial suspension containing approximately 5 × 10 CFU/ml B. pertussis. The immunogenicity of the tested vaccines against PT (pertussis toxin), PRN (pertactin), FHA (filamentous haemagglutinin) and FIM (fimbriae types 2 and 3) was examined. The commercial whole-cell and acellular pertussis vaccines induced an immunity effective at eliminating the genetically different B. pertussis isolates from the lungs. However, the elimination of the PRN-deficient isolate from the lungs of mice vaccinated with commercial vaccines was delayed as compared to the PRN ( +) isolate, suggesting phenotypic differences with the circulating isolates and vaccine strains. The most effective vaccine was the experimental vaccine with the composition identical to that of the strains used for infection.
Topics: Animals; Antibodies, Bacterial; Bacterial Load; Bordetella pertussis; Diphtheria-Tetanus-Pertussis Vaccine; Diphtheria-Tetanus-acellular Pertussis Vaccines; Female; Genetic Profile; Immunogenicity, Vaccine; Lung; Mice; Mice, Inbred BALB C; Multilocus Sequence Typing; Pertussis Vaccine; Vaccine Efficacy; Whooping Cough
PubMed: 34338880
DOI: 10.1007/s00430-021-00718-1 -
PloS One 2020Bordetella pertussis is the causative agent of whooping cough, commonly referred to as pertussis. Although the incidence of pertussis was reduced through vaccination,...
Bordetella pertussis is the causative agent of whooping cough, commonly referred to as pertussis. Although the incidence of pertussis was reduced through vaccination, during the last thirty years it has returned to high levels in a number of countries. This resurgence has been linked to the switch from the use of whole-cell to acellular vaccines. Protection afforded by acellular vaccines appears to be short-lived compared to that afforded by whole cell vaccines. In order to inform future vaccine improvement by identifying immune correlates of protection, a human challenge model of B. pertussis colonisation has been developed. Accurate measurement of colonisation status in this model has required development of a qPCR-based assay to enumerate B. pertussis in samples that distinguishes between viable and dead bacteria. Here we report the development of this assay and its performance in the quantification of B. pertussis from human challenge model samples. This assay has future utility in diagnostic labs and in research where a quantitative measure of both B. pertussis number and viability is required.
Topics: Bordetella pertussis; Humans; Molecular Diagnostic Techniques; Polymerase Chain Reaction; Sensitivity and Specificity; THP-1 Cells
PubMed: 32353041
DOI: 10.1371/journal.pone.0232334 -
Clinical Microbiology Reviews Oct 1988Bordetella pertussis, the causative agent of whooping cough, produces an acute and chronic respiratory infection in infants and young children. B. pertussis is still a... (Review)
Review
Bordetella pertussis, the causative agent of whooping cough, produces an acute and chronic respiratory infection in infants and young children. B. pertussis is still a major health problem of young children throughout the world even though effective immunization against whooping cough is available. While predominantly a childhood disease, it has been reported also to be a cause of persistent cough in adults. This review discusses the numerous bacterial virulence factors that may play roles in the pathogenesis of pertussis and in immunity to infection. The present problems with pertussis diagnosis, recent advances, and future prospects for new and improved rapid diagnostics tests also are explored.
Topics: Bordetella pertussis; Humans; Virulence Factors, Bordetella; Whooping Cough
PubMed: 2906814
DOI: 10.1128/CMR.1.4.365 -
MSphere Aug 2021Bordetella pertussis has been shown to encode regulatory RNAs, yet the posttranscriptional regulatory circuits on which they act remain to be fully elucidated. We...
RNase III and RNase E Influence Posttranscriptional Regulatory Networks Involved in Virulence Factor Production, Metabolism, and Regulatory RNA Processing in Bordetella pertussis.
Bordetella pertussis has been shown to encode regulatory RNAs, yet the posttranscriptional regulatory circuits on which they act remain to be fully elucidated. We generated mutants lacking the endonucleases RNase III and RNase E and assessed their individual impact on the B. pertussis transcriptome. Transcriptome sequencing (RNA-Seq) analysis showed differential expression of ∼25% of the B. pertussis transcriptome in each mutant, with only 28% overlap between data sets. Both endonucleases exhibited substantial impact on genes involved in amino acid uptake (e.g., ABC transporters) and in virulence (e.g., the type III secretion system and the autotransporters , , and ). Interestingly, mutations in RNase III and RNase E drove the stability of many transcripts, including those involved in virulence, in opposite directions, a result that was validated by qPCR and immunoblotting for and . Of note, whereas similar mutations to RNase E in Escherichia coli have subtle effects on transcript stability, a striking >20-fold reduction in four gene transcripts, including and , was observed in B. pertussis. We further compared our data set to the regulon controlled by the RNA chaperone Hfq to identify B. pertussis loci influenced by regulatory RNAs. This analysis identified ∼120 genes and 19 operons potentially regulated at the posttranscriptional level. Thus, our findings revealed how changes in RNase III- and RNase E-mediated RNA turnover influence pathways associated with virulence and cellular homeostasis. Moreover, we highlighted loci potentially influenced by regulatory RNAs, providing insights into the posttranscriptional regulatory networks involved in fine-tuning B. pertussis gene expression. Noncoding, regulatory RNAs in bacterial pathogens are critical components required for rapid changes in gene expression profiles. However, little is known about the role of regulatory RNAs in the growth and pathogenesis of Bordetella pertussis. To address this, mutants separately lacking ribonucleases central to regulatory RNA processing, RNase III and RNase E, were analyzed by RNA-Seq. Here, we detail the first transcriptomic analysis of the impact of altered RNA degradation in B. pertussis. Each mutant showed approximately 1,000 differentially expressed genes, with significant changes in the expression of pathways associated with metabolism, bacterial secretion, and virulence factor production. Our analysis suggests an important role for these ribonucleases during host colonization and provides insights into the breadth of posttranscriptional regulation in B. pertussis, further informing our understanding of B. pertussis pathogenesis.
Topics: Bacterial Proteins; Bordetella pertussis; Endoribonucleases; Gene Expression Profiling; Gene Expression Regulation, Bacterial; Mutation; RNA Processing, Post-Transcriptional; Regulon; Ribonuclease III; Transcriptome; Virulence; Virulence Factors
PubMed: 34406853
DOI: 10.1128/mSphere.00650-21 -
Biochimica Et Biophysica Acta.... Dec 2019BteA, a 69-kDa cytotoxic protein, is a type III secretion system (T3SS) effector in the classical Bordetella, the etiological agents of pertussis and related mammalian...
BteA, a 69-kDa cytotoxic protein, is a type III secretion system (T3SS) effector in the classical Bordetella, the etiological agents of pertussis and related mammalian respiratory diseases. Like other cytotoxicity-mediating effectors, BteA uses its multifunctional N-terminal domain to target phosphatidylinositol (PI)-rich microdomains in the host membrane. Despite their structural similarity, T3SS effectors exhibit a variable range of membrane interaction modes, and currently only limited structural information is available for the BteA membrane-targeting domain and the molecular mechanisms underlying its function. Employing a synergistic combination of structural methods, here we determine the structure of this functional domain and uncover key molecular determinants mediating its interaction with membranes. Residues 29-121 of BteA form an elongated four-helix bundle packed against two shorter perpendicular helices, the second of which caps the domain in a critical 'tip motif'. A flexible region preceding the BteA helical bundle contains the characteristic β-motif required for binding its cognate chaperone BtcA. We show that BteA targets PI(4,5)P-containing lipoprotein nanodiscs and binds a soluble PI(4,5)P analog via an extensive positively charged surface spanning its first two helices, and that this interaction is weaker for PI(3,5)P and abolished for PI(4)P. We confirmed this model of membrane-targeting by observation of BteA-induced changes in the structure of PI(4,5)P-containing phospholipid bilayers using small-angle X-ray scattering (SAXS). We also extended these results to a larger BteA domain (residues 1-287), confirming its interaction with bilayers using calorimetry, fluorescence and SAXS methods. This novel view of the structural underpinnings of membrane targeting by BteA is an important step towards a comprehensive understanding of cytotoxicity in Bordetella, as well as interactions of a broad range of pathogens with their respective hosts.
Topics: Amino Acid Sequence; Bacterial Proteins; Bordetella pertussis; Crystallography, X-Ray; Cytotoxicity, Immunologic; Membrane Proteins; Molecular Chaperones; Phosphatidylinositols; Protein Binding; Scattering, Small Angle; Structure-Activity Relationship; Type III Secretion Systems; X-Ray Diffraction
PubMed: 31487494
DOI: 10.1016/j.bbamem.2019.183054 -
Archives of Razi Institute Mar 2019Whole-cell pertussis vaccine (wP) has been imperative and highly effective in preventing childhood deaths due to pertussis. Pertussis toxin is one of the virulence...
Whole-cell pertussis vaccine (wP) has been imperative and highly effective in preventing childhood deaths due to pertussis. Pertussis toxin is one of the virulence factors of Bordetella pertussis in all available pertussis vaccines. wP production in Razi Vaccine and Serum Research Institute is according to bioreactor culture of B. pertussis strains in B2 medium. The aim of this study was to evaluate B. pertussis strain 509 PT production in B2 and Thalen-IJssel (THIJS) media by Chinese Hamster Ovary (CHO) cell and enzyme-linked immunosorbent assay methods (ELISA). In the current study, B. pertussis strain 509 was cultured in B2 and THIJS media. Six samples were taken during the log growth phase within 2-3 h intervals (triplicate). The growth rate was calculated using opacity and the quantification of cell-associated and released PT measured by ELISA and CHO cell assays. THIJS medium was significantly showed an increase in the bacterial growth rate. During the first 29 h, bacterial concentrations in B2 and THIJS culture medium were 19 and 29 IOU, respectively. In THIJS medium, greater amount of pertussistoxin production was cell-associated. In B2 medium, maximum cell-associated toxin by ELISA and CHO cell assays were in the ODs of 1.1 and 0.9 and for THIJS medium in the ODs of 1.6 and 1.1, respectively. B. pertussis strain 509 in THIJS medium produced higher cell mass and cell-associated pertussis toxin than that of B2. It can be used for the production of whole-cell vaccine with higher pertussis toxin and accordingly using lower biomass per dose leading to the reduction of vaccine toxicity.
Topics: Animals; Bordetella pertussis; CHO Cells; Cricetulus; Culture Media; Enzyme-Linked Immunosorbent Assay; Pertussis Toxin; Pertussis Vaccine
PubMed: 31013007
DOI: 10.22092/ari.2018.110249.1124 -
Communications Biology Jan 2021Copper is both essential and toxic to living beings, which tightly controls its intracellular concentration. At the host-pathogen interface, copper is used by phagocytic...
Copper is both essential and toxic to living beings, which tightly controls its intracellular concentration. At the host-pathogen interface, copper is used by phagocytic cells to kill invading microorganisms. We investigated copper homeostasis in Bordetella pertussis, which lives in the human respiratory mucosa and has no environmental reservoir. B. pertussis has considerably streamlined copper homeostasis mechanisms relative to other Gram-negative bacteria. Its single remaining defense line consists of a metallochaperone diverted for copper passivation, CopZ, and two peroxide detoxification enzymes, PrxGrx and GorB, which together fight stresses encountered in phagocytic cells. Those proteins are encoded by an original, composite operon assembled in an environmental ancestor, which is under sensitive control by copper. This system appears to contribute to persistent infection in the nasal cavity of B. pertussis-infected mice. Combining responses to co-occurring stresses in a tailored operon reveals a strategy adopted by a host-restricted pathogen to optimize survival at minimal energy expenditure.
Topics: Bordetella bronchiseptica; Bordetella pertussis; Copper; Homeostasis; Operon; Peroxides
PubMed: 33420409
DOI: 10.1038/s42003-020-01580-2 -
Revista Chilena de Infectologia :... Jun 2012
Topics: Bordetella pertussis; Humans; Severity of Illness Index; Whooping Cough
PubMed: 23096463
DOI: 10.4067/S0716-10182012000300001 -
BMC Infectious Diseases Aug 2016The clinical diagnosis of pertussis is not easy in early infancy since clinical manifestations can overlap with several different diseases. Many cases are often...
BACKGROUND
The clinical diagnosis of pertussis is not easy in early infancy since clinical manifestations can overlap with several different diseases. Many cases are often misclassified and underdiagnosed. We conducted a retrospective study on infants to assess how often physicians suspected pertussis and the actual frequency of Bordetella pertussis infections.
METHODS
We analyzed all infants with age ≤90 days hospitalized from March 2011 until September 2013 for acute respiratory symptoms tested with a Real Time Polymerase Chain Reaction able to detect Bordetella pertussis and with a Real Time Polymerase Chain Reaction for a multipanel respiratory virus. Therefore, we compared patients with pertussis positive aspirate, patients with respiratory virus positive aspirate and patients with negative aspirate to identify symptoms or clinical findings predictive of pertussis.
RESULTS
Out of 215 patients analyzed, 53 were positive for pertussis (24.7 %), 119 were positive for respiratory virus (55.3 %) and 43 had a negative aspirate (20 %). Pertussis was suspected in 22 patients at admission and 16 of them were confirmed by laboratory tests, while 37 infants with different admission diagnosis resulted positive for pertussis. The sensitivity of clinical diagnosis was 30.2 % and the specificity 96.3 %. Infants with pertussis had more often paroxysmal cough, absence of fever and a higher absolute lymphocyte count than infants without pertussis.
CONCLUSIONS
Pertussis is a serious disease in infants and it is often unrecognized; some features should help pediatricians to suspect pertussis, but clinical suspicion has a low sensitivity. We suggest a systematic use of Real Time Polymerase Chain Reaction to support the clinical suspicion of pertussis in patients with less than 3 months of age hospitalized with acute respiratory symptoms.
Topics: Bordetella pertussis; DNA, Bacterial; Female; Humans; Infant; Infant, Newborn; Male; Odds Ratio; Real-Time Polymerase Chain Reaction; Retrospective Studies; Sensitivity and Specificity; Whooping Cough
PubMed: 27528377
DOI: 10.1186/s12879-016-1710-0 -
Pathogens and Disease Nov 2015
Topics: Biomedical Research; Bordetella pertussis; Communicable Disease Control; Communicable Diseases, Emerging; Disease Transmission, Infectious; Humans; Whooping Cough
PubMed: 26490977
DOI: 10.1093/femspd/ftv090