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Frontiers in Cellular and Infection... 2023are respiratory pathogens comprised of three classical species: , and . With recent surges in spp. cases and antibiotics becoming less effective to combat infectious...
spp. utilize the type 3 secretion system to manipulate the VIP/VPAC2 signaling and promote colonization and persistence of the three classical in the lower respiratory tract.
INTRODUCTION
are respiratory pathogens comprised of three classical species: , and . With recent surges in spp. cases and antibiotics becoming less effective to combat infectious diseases, there is an imperative need for novel antimicrobial therapies. Our goal is to investigate the possible targets of host immunomodulatory mechanisms that can be exploited to promote clearance of spp. infections. Vasoactive intestinal peptide (VIP) is a neuropeptide that promotes Th2 anti-inflammatory responses through VPAC1 and VPAC2 receptor binding and activation of downstream signaling cascades.
METHODS
We used classical growth assays to evaluate the effects of VIP on spp. growth and survival. Using the three classical spp. in combination with different mouse strains we were able to evaluate the role of VIP/VPAC2 signaling in the infectious dose 50 and infection dynamics. Finally using the murine model we determine the suitability of VPAC2 antagonists as possible therapy for spp. infections.
RESULTS
Under the hypothesis that inhibition of VIP/VPAC2 signaling would promote clearance, we found that VPAC2 mice, lacking a functional VIP/VPAC2 axis, hinder the ability of the bacteria to colonize the lungs, resulting in decreased bacterial burden by all three classical species. Moreover, treatment with VPAC2 antagonists decrease lung pathology, suggesting its potential use to prevent lung damage and dysfunction caused by infection. Our results indicate that the ability of spp. to manipulate VIP/VPAC signaling pathway appears to be mediated by the type 3 secretion system (T3SS), suggesting that this might serve as a therapeutical target for other gram-negative bacteria.
CONCLUSION
Taken together, our findings uncover a novel mechanism of bacteria-host crosstalk that could provide a target for the future treatment for whooping cough as well as other infectious diseases caused primarily by persistent mucosal infections.
Topics: Animals; Mice; Bordetella Infections; Bordetella pertussis; Lung; Receptors, Vasoactive Intestinal Peptide, Type II; Signal Transduction; Type III Secretion Systems; Vasoactive Intestinal Peptide
PubMed: 37065208
DOI: 10.3389/fcimb.2023.1111502 -
Anales de Pediatria Oct 2022Pertussis is a respiratory infection caused by bacteria of the genus Bordetella, mainly pertussis and parapertussis species. Despite the high vaccination coverage in...
INTRODUCTION
Pertussis is a respiratory infection caused by bacteria of the genus Bordetella, mainly pertussis and parapertussis species. Despite the high vaccination coverage in developed countries, it is considered a re-emerging disease that is also underreported and underdiagnosed, especially in patients who do not require hospital referral.
MATERIAL AND METHODS
Descriptive, prospective and multicentre study of pertussis diagnosis and contact investigation in 17 primary care paediatric clinics through collection of samples for polymerase chain reaction (PCR) testing over a period of 4 years and after the implementation of routine vaccination against pertussis during pregnancy.
RESULTS
Pertussis was diagnosed in a total of 50 patients; the estimated incidence in these years was higher compared to previous rates in the paediatric age group. Fourteen percent of the cases occurred in children aged less than 1 year. The mean age was 6.7 years. Cough was present in 100% of cases, followed in frequency by vomiting and rhinorrhoea. Only 1 patient required hospital admission, and none died or developed complications. B. pertussis was the predominant causative agent. Only 40% knew the source of infection. In 26% of the cases, pertussis was confirmed in contacts of the patient by PCR, and in 46% it was suspected based on the clinical presentation but without microbiological confirmation.
CONCLUSIONS
Access to diagnostic tests (PCR) for pertussis in primary care allows us to optimise its diagnosis and treatment, to break the chain of transmission, to know the real incidence rates and to assess the impact of routine vaccination of pregnant women on this disease.
Topics: Bordetella pertussis; Child; Female; Humans; Polymerase Chain Reaction; Pregnancy; Primary Health Care; Prospective Studies; Whooping Cough
PubMed: 35995698
DOI: 10.1016/j.anpede.2022.02.005 -
PloS One 2017B. parapertussis is a whooping cough etiological agent with the ability to evade the immune response induced by pertussis vaccines. We previously demonstrated that in...
B. parapertussis is a whooping cough etiological agent with the ability to evade the immune response induced by pertussis vaccines. We previously demonstrated that in the absence of opsonic antibodies B. parapertussis hampers phagocytosis by neutrophils and macrophages and, when phagocytosed, blocks intracellular killing by interfering with phagolysosomal fusion. But neutrophils can kill and/or immobilize extracellular bacteria through non-phagocytic mechanisms such as degranulation and neutrophil extracellular traps (NETs). In this study we demonstrated that B. parapertussis also has the ability to circumvent these two neutrophil extracellular bactericidal activities. The lack of neutrophil degranulation was found dependent on the O antigen that targets the bacteria to cell lipid rafts, eventually avoiding the fusion of nascent phagosomes with specific and azurophilic granules. IgG opsonization overcame this inhibition of neutrophil degranulation. We further observed that B. parapertussis did not induce NETs release in resting neutrophils and inhibited NETs formation in response to phorbol myristate acetate (PMA) stimulation by a mechanism dependent on adenylate cyclase toxin (CyaA)-mediated inhibition of reactive oxygen species (ROS) generation. Thus, B. parapertussis modulates neutrophil bactericidal activity through two different mechanisms, one related to the lack of proper NETs-inducer stimuli and the other one related to an active inhibitory mechanism. Together with previous results these data suggest that B. parapertussis has the ability to subvert the main neutrophil bactericidal functions, inhibiting efficient clearance in non-immune hosts.
Topics: Antibodies, Bacterial; Bordetella Infections; Bordetella parapertussis; Extracellular Traps; Humans; Macrophages; Membrane Microdomains; Neutrophils; Phagocytosis; Phagosomes
PubMed: 28095485
DOI: 10.1371/journal.pone.0169936 -
Emerging Infectious Diseases Apr 2022An increase in positive Bordetella parapertussis tests among patients in a teaching hospital in the Netherlands resulted in enhanced infection control and...
An increase in positive Bordetella parapertussis tests among patients in a teaching hospital in the Netherlands resulted in enhanced infection control and microbiological surveillance. Further analysis revealed that batches of contaminated nasopharyngeal swabs were associated with a pseudo-outbreak, resulting in incorrect diagnoses, antimicrobial treatments, isolation precautions, and public health notifications.
Topics: Bordetella Infections; Bordetella parapertussis; Bordetella pertussis; Disease Outbreaks; Humans; Netherlands
PubMed: 35318925
DOI: 10.3201/eid2804.212097 -
Frontiers in Cellular and Infection... 2021The genus is divided into two groups: classical and non-classical. , and are known as classical bordetellae, a group of important human pathogens causing whooping...
The genus is divided into two groups: classical and non-classical. , and are known as classical bordetellae, a group of important human pathogens causing whooping cough or whooping cough-like disease and hypothesized to have evolved from environmental non-classical bordetellae. infections have increased globally driving the need to better understand these pathogens for the development of new treatments and vaccines. One unexplored component in is the role of serine, threonine and tyrosine phosphorylation. Therefore, this study characterized the phosphoproteome of classical bordetellae and examined its potential role in biology and virulence. Applying strict identification of localization criteria, this study identified 70 unique phosphorylated proteins in the classical group with a high degree of conservation. Phosphorylation was a key regulator of metabolism with proteins involved in gluconeogenesis, TCA cycle, amino acid and nucleotide synthesis significantly enriched. Three key virulence pathways were also phosphorylated including type III secretion system, alcaligin synthesis and the BvgAS master transcriptional regulatory system for virulence genes in . Seven new phosphosites were identified in BvgA with 6 located in the DNA binding domain. Of the 7, 4 were not present in non-classical bordetellae. This suggests that serine/threonine phosphorylation may play an important role in stabilizing/destabilizing BvgA binding to DNA for fine-tuning of virulence gene expression and that BvgA phosphorylation may be an important factor separating classical from non-classical bordetellae. This study provides the first insight into the phosphoproteome of classical species and the role that Ser/Thr/Tyr phosphorylation may play in biology and virulence.
Topics: Bacterial Proteins; Biology; Humans; Phosphorylation; Serine; Threonine; Tyrosine; Virulence
PubMed: 33928046
DOI: 10.3389/fcimb.2021.660280 -
Journal of Clinical Microbiology May 2019The Aries assay (Aries BA) (Luminex Corporation) recently received FDA clearance for the detection and differentiation of and nucleic acids in nasopharyngeal swab... (Comparative Study)
Comparative Study
The Aries assay (Aries BA) (Luminex Corporation) recently received FDA clearance for the detection and differentiation of and nucleic acids in nasopharyngeal swab (NPS) samples. The objective of this study was to evaluate the performance of the Aries BA in comparison to that of the BioFire FilmArray respiratory panel (RP). The Aries BA was evaluated using retrospective, remnant nasopharyngeal swabs (NPS), previously tested by FilmArray RP. Performance characteristics evaluated included positive percent agreement (PPA) and negative percent agreement (NPA) with the FilmArray RP. Discordant analysis was performed using bidirectional sequencing. A time and motion study was performed to compare the laboratory workflow of the two tests. Three hundred samples were included in the study. There were no samples positive for The PPA and NPA of the Aries BA were 61.1% (95% confidence interval [CI], 35.8 to 82.7%) and 100% (95% CI, 98.7 to 100%). Discordant results included five results that were incorrectly identified as by the FilmArray RP and one false-negative result for both the Aries BA and the FilmArray RP. The overall agreement between the Aries BA and FilmArray RP for the detection of was considered good at 97.7% with a kappa value of 0.71 (95% CI, 0.51 to 0.9). The Aries BA offers a new diagnostic option for the rapid and targeted approach to the diagnosis of pertussis. Unlike the FilmArray RP, the Aries BA did not cross-react with in our study, although a larger sample set should be tested to confirm this finding.
Topics: Bordetella pertussis; Cross Reactions; DNA, Bacterial; Humans; Molecular Diagnostic Techniques; Nasopharynx; Oligonucleotide Array Sequence Analysis; Reproducibility of Results; Retrospective Studies; Time and Motion Studies; Whooping Cough
PubMed: 30787143
DOI: 10.1128/JCM.01966-18 -
Journal of Clinical Microbiology Jan 2019This study aimed to validate a comprehensive diagnostic protocol based on real-time PCR for the rapid detection and identification of , , and , as well as its...
Validation and Implementation of a Diagnostic Algorithm for DNA Detection of Bordetella pertussis, B. parapertussis, and B. holmesii in a Pediatric Referral Hospital in Barcelona, Spain.
This study aimed to validate a comprehensive diagnostic protocol based on real-time PCR for the rapid detection and identification of , , and , as well as its implementation in the diagnostic routine of a reference children's hospital. The new algorithm included a triplex quantitative PCR (qPCR) targeting IS gene (in , , and some strains), pIS (-specific) and P as the human internal control. Two confirmatory singleplex tests for (-Pr) and (hIS) were performed if IS was positive. Analytical validation included determination of linear range, linearity, efficiency, precision, sensitivity, and a reference panel with clinical samples. Once validated, the new algorithm was prospectively implemented in children with clinical suspicion of whooping cough presenting to Hospital Sant Joan de Deu (Barcelona, Spain) over 12 months. Lower limits of detection obtained were 4.4, 13.9, and 27.3 genomic equivalents/ml of sample for IS (on ), pIS and hIS, and 777.9 for -Pr. qPCR efficiencies ranged from 86.0% to 96.9%. Intra- and interassay variabilities were <3% and <5%, respectively. Among 566 samples analyzed, , , and were detected in 11.1%, 0.9% (only in females >4 years old), and 0.2% of samples, respectively. The new algorithm proved to be a useful microbiological diagnostic tool for whooping cough, demonstrating a low rate of other non- species in our surveilled area.
Topics: Adolescent; Algorithms; Bacteriological Techniques; Bordetella; Bordetella Infections; Child; Child, Preschool; DNA, Bacterial; Diagnostic Tests, Routine; Female; Genes, Bacterial; Hospitals, Pediatric; Humans; Infant; Infant, Newborn; Limit of Detection; Male; Nasopharynx; Real-Time Polymerase Chain Reaction; Spain; Whooping Cough
PubMed: 30404946
DOI: 10.1128/JCM.01231-18 -
Microbiology Spectrum Jun 2023The classical species infect the respiratory tract of mammals. While B. bronchiseptica causes rather chronic respiratory infections in a variety of mammals, the...
The classical species infect the respiratory tract of mammals. While B. bronchiseptica causes rather chronic respiratory infections in a variety of mammals, the human-adapted species B. pertussis and cause an acute respiratory disease known as whooping cough or pertussis. The virulence factors include a type III secretion system (T3SS) that translocates effectors BteA and BopN into host cells. However, the regulatory mechanisms underlying the secretion and translocation activity of T3SS in bordetellae are largely unknown. We have solved the crystal structure of BopN of B. pertussis and show that it is similar to the structures of gatekeepers that control access to the T3SS channel from the bacterial cytoplasm. We further found that BopN accumulates at the cell periphery at physiological concentrations of calcium ions (2 mM) that inhibit the secretion of BteA and BopN. Deletion of the gene in B. bronchiseptica increased secretion of the BteA effector into calcium-rich medium but had no effect on secretion of the T3SS translocon components BopD and BopB. Moreover, the Δ mutant secreted approximately 10-fold higher amounts of BteA into the medium of infected cells than the wild-type bacteria, but it translocated lower amounts of BteA into the host cell cytoplasm. These data demonstrate that BopN is a T3SS gatekeeper required for regulated and targeted translocation of the BteA effector through the T3SS injectisome into host cells. The T3SS is utilized by many Gram-negative bacteria to deliver effector proteins from bacterial cytosol directly into infected host cell cytoplasm in a regulated and targeted manner. Pathogenic bordetellae use the T3SS to inject the BteA and BopN proteins into infected cells and upregulate the production of the anti-inflammatory cytokine interleukin-10 (IL-10) to evade host immunity. Previous studies proposed that BopN acted as an effector in host cells. In this study, we report that BopN is a T3SS gatekeeper that regulates the secretion and translocation activity of T3SS.
Topics: Animals; Humans; Type III Secretion Systems; Whooping Cough; Calcium; Bordetella pertussis; Virulence Factors; Bacterial Proteins; Mammals
PubMed: 37036369
DOI: 10.1128/spectrum.04112-22 -
Journal of Medical Microbiology Oct 2021Whooping cough (pertussis) is a highly contagious respiratory bacterial infection caused by and is an important cause of morbidity and mortality worldwide, particularly...
Whooping cough (pertussis) is a highly contagious respiratory bacterial infection caused by and is an important cause of morbidity and mortality worldwide, particularly in infants. can cause a similar, but usually less severe pertussis-like disease. has a number of virulence factors including adhesins and toxins which allow the organism to bind to ciliated epithelial cells in the upper respiratory tract and interfere with host clearance mechanisms. Typical symptoms of pertussis include paroxysmal cough with characteristic whoop and vomiting. Severe complications and deaths occur mostly in infants. Laboratory confirmation can be performed by isolation, detection of genomic DNA or specific antibodies. Childhood vaccination is safe, effective and remains the best control method available. Many countries have replaced whole-cell pertussis vaccines (wP) with acellular pertussis vaccines (aP). Waning protection following immunisation with aP is considered to be more rapid than that from wP. Deployed by resource-rich countries to date, maternal immunisation programmes have also demonstrated high efficacy in preventing hospitalisation and death in infants by passive immunisation through transplacental transfer of maternal antibodies.
Topics: Bordetella parapertussis; Bordetella pertussis; Humans; Infant; Pertussis Vaccine; Virulence Factors; Whooping Cough
PubMed: 34668853
DOI: 10.1099/jmm.0.001442 -
PloS One 2015The classical bordetellae are comprised of three subspecies that differ from broad to very limited host specificity. Although several lineages appear to have specialized...
The classical bordetellae are comprised of three subspecies that differ from broad to very limited host specificity. Although several lineages appear to have specialized to particular host species, most retain the ability to colonize and grow in mice, providing a powerful common experimental model to study their differences. One of the subspecies, Bordetella parapertussis, is composed of two distinct clades that have specialized to different hosts: one to humans (Bpphu), and the other to sheep (Bppov). While Bpphu and the other classical bordetellae can efficiently colonize mice, Bppov strains are severely defective in their ability to colonize the murine respiratory tract. Bppov genomic analysis did not reveal the loss of adherence genes, but substantial mutations and deletions of multiple genes involved in the production of O-antigen, which is required to prevent complement deposition on B. bronchiseptica and Bpphu strains. Bppov lacks O-antigen and, like O-antigen mutants of other bordetellae, is highly sensitive to murine complement-mediated killing in vitro. Based on these results, we hypothesized that Bppov failed to colonize mice because of its sensitivity to murine complement. Consistent with this, the Bppov defect in the colonization of wild type mice was not observed in mice lacking the central complement component C3. Furthermore, Bppov strains were highly susceptible to killing by murine complement, but not by sheep complement. These data demonstrate that the failure of Bppov to colonize mice is due to sensitivity to murine, but not sheep, complement, providing a mechanistic example of how specialization that accompanies expansion in one host can limit host range.
Topics: Animals; Bordetella Infections; Bordetella bronchiseptica; Bordetella parapertussis; Complement C3; Complement System Proteins; Host Specificity; Humans; Lung; Mice, Inbred C57BL; Mice, Knockout; Nasal Cavity; O Antigens; Sheep; Sheep Diseases; Species Specificity; Trachea; Virulence
PubMed: 26158540
DOI: 10.1371/journal.pone.0130964