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Analysis of Bordetella pertussis pertactin and pertussis toxin types from Queensland, Australia, 1999–2003
Shane Byrne, Andrew T Slack
BMC Infectious Diseases , 2006, DOI: 10.1186/1471-2334-6-53
Abstract: Forty-six B. pertussis isolates recovered from Queensland patients between 1999 and 2003 were examined by both DNA sequencing and LightCycler? real time PCR to determine their pertactin and pertussis toxin subunit 1 genotypes.Pertactin typing showed that 38 isolates possessed the prn1 allele, 3 possessed the prn2 allele and 5 possessed the prn3 allele. All forty-six isolates possessed the pertussis toxin ptxS1A genotype. Amongst the circulating B. pertussis population in Queensland, 82.5% of the recovered clinical isolates therefore possessed the prn1/ptxS1A genotype.The results of this study compared to historical research on Queensland isolates suggest that B. pertussis pertactin and pertussis toxin variants are not becoming more prevalent in Queensland since the introduction of the acellular vaccines. Current prevalences of pertactin variants are significantly different to that described in a number of other countries with high vaccine coverage. Relative paucity of recovered isolates compared to notified infections, due primarily to non culture based pertussis diagnostics is however a confounding factor in the assessment of variant prevalence.Bordetella pertussis, the etiological agent of 'Whooping Cough' remains prevalent in Australia despite the introduction and wide spread use of pertussis vaccines as part of the childhood immunisation scheme. The Australian standard vaccination schedule for pertussis consists of acellular vaccines given in doses at 2, 4 and 6 months, followed by a fourth dose at 4 years and a booster at 15–17 years of age [1]. Prior to 1999 a local whole cell vaccine was in use beginning in the decade 1936–1945. [2]. An 'Immunise Australia' program established in 1997 has set a target of 90% coverage for pertussis vaccination [2]. In the Australian state of Queensland pertussis vaccine coverage in the 1990s moved from the high 70% to mid 80%, and then rose above the 90% target from 2001 onwards [2-4]. In spite of this high vaccine coverage, i
Prevalence and Genetic Characterization of Pertactin-Deficient Bordetella pertussis in Japan  [PDF]
Nao Otsuka, Hyun-Ja Han, Hiromi Toyoizumi-Ajisaka, Yukitsugu Nakamura, Yoshichika Arakawa, Keigo Shibayama, Kazunari Kamachi
PLOS ONE , 2012, DOI: 10.1371/journal.pone.0031985
Abstract: The adhesin pertactin (Prn) is one of the major virulence factors of Bordetella pertussis, the etiological agent of whooping cough. However, a significant prevalence of Prn-deficient (Prn?) B. pertussis was observed in Japan. The Prn? isolate was first discovered in 1997, and 33 (27%) Prn? isolates were identified among 121 B. pertussis isolates collected from 1990 to 2009. Sequence analysis revealed that all the Prn? isolates harbor exclusively the vaccine-type prn1 allele and that loss of Prn expression is caused by 2 different mutations: an 84-bp deletion of the prn signal sequence (prn1ΔSS, n = 24) and an IS481 insertion in prn1 (prn1::IS481, n = 9). The frequency of Prn? isolates, notably those harboring prn1ΔSS, significantly increased since the early 2000s, and Prn? isolates were subsequently found nationwide. Multilocus variable-number tandem repeat analysis (MLVA) revealed that 24 (73%) of 33 Prn? isolates belong to MLVA-186, and 6 and 3 Prn? isolates belong to MLVA-194 and MLVA-226, respectively. The 3 MLVA types are phylogenetically closely related, suggesting that the 2 Prn? clinical strains (harboring prn1ΔSS and prn1::IS481) have clonally expanded in Japan. Growth competition assays in vitro also demonstrated that Prn? isolates have a higher growth potential than the Prn+ back-mutants from which they were derived. Our observations suggested that human host factors (genetic factors and immune status) that select for Prn? strains have arisen and that Prn expression is not essential for fitness under these conditions.
Effects of Inactivated Bordetella pertussis on Phosphodiesterase in the Lung of Ovalbumin Sensitized and Challenged Rats  [PDF]
Ya-Juan Wang,Shun-De Song,Jun-Chun Chen,Xue-Feng Wang,Ya-Li Jiang,Qiang-Min Xie,Ji-Qiang Chen,Zi-Gang Li,Hui-Fang Tang
Pulmonary Medicine , 2014, DOI: 10.1155/2014/581738
Abstract: This paper indicated that inactivated Bordetella pertussis (iBp) can enhance the lung airway hyperreactivity of the rats sensitized and challenged with OVA. The mechanisms were involved in the upregulation of cAMP-PDE activity and PDE4A, PDE4D, and PDE3 gene expression in the lungs. But only PDE4 activity was different between the OVA and OVA+iBp groups, and PDE4D expression was significantly increased in iBp rats alone. So, our data suggested that cosensitization with OVA and iBp affects lung airway reactivity by modulating the lung cAMP-PDE activity and PDE4D gene expression. 1. Introduction Inactivated Bordetella pertussis (iBp) has been used as a strong Th2 adjuvant to boost allergic responses to antigen such as house dust mite antigen (HDM), ovalbumin (OVA), and ragweed pollen in animal models of asthmatic hypersensitivity from 1968 [1–4]. Systemic administration of iBp enhances these sensitization processes and enhances the pulmonary and systemic immune responses to locally administered HDM [5]. Our experiments have also suggested that simultaneous exposure to OVA and intramuscularly iBp can enhance the bronchial hyperresponsiveness [6]. But how this occurs at the molecular level has not been elucidated. The phosphodiesterase (PDE) superfamily participates in the only cellular pathways for degradation of the ubiquitous intracellular second messengers. It comprises eleven biochemically and pharmacologically distinct enzyme families (PDEs 1-11) that hydrolyze cAMP and/or cGMP [7]. PDE4 is specific for cAMP and comprises four subtypes (A, B, C, and D). It is predominantly expressed and plays an important role in the regulation of cellular functions in inflammatory and immune cells. There has been significant interest in PDE4 inhibitors as a potential therapy for inflammatory diseases such as allergy and asthma [8]. Cyclic adenosine monophosphate (cAMP) relaxes airway smooth muscles in the lung. Our previous study using iBp adjuvants suggested that PDE4 is upregulated in the lung of allergic rats [6]. But whether the adjuvants had effects on PDE activity and expression was unclear. Growing evidence suggests that the D subtype of PDE4-PDE4D plays a key role in balancing relaxation and contraction in airway smooth muscle [9]. The airway smooth muscle contractility of PDE4D-deficient mice is disrupted and no longer responsive to cholinergic stimulation [10]. Interestingly, animals exposed prenatally but not postnatally to cigarette smoke show increased airway hyperresponsiveness after a single intratracheal injection of Aspergillus fumigatus extract.
Production and characterization of recombinant pertactin, fimbriae 2 and fimbriae 3 from Bordetella pertussis
Yinghua Xu, Yaying Wang, Yajun Tan, Huajie Zhang, Lijie Wu, Lichan Wang, Qiming Hou, Shumin Zhang
BMC Microbiology , 2009, DOI: 10.1186/1471-2180-9-274
Abstract: Three recombinant proteins with amount of 12 to 25 mg/L were produced. Compared to the control mice only immunized with adjuvant, serum IgG antibody responses were significantly induced in the mice immunized with rPrn, rFim2 or rFim3 (P < 0.001 for all three proteins). Furthermore, T cell responses characteristic of increased production of IL-2 and TNF-α (only for rPrn) were elicited in the mice immunized with the three proteins (P < 0.05 for all three proteins). Immunization with rPrn, but not with rFim2 or rFim3, significantly enhanced clearance of bacteria in the lungs of mice after intranasal challenge with B. pertussis (P < 0.05). When tested in a lethal intracerebral infection model, certain protection was observed in mice immunized with rPrn.We have developed an efficient method to produce large amounts of rPrn, rFim2, and rFim3 from B. pertussis. The three recombinant proteins induced both humoral and cellular immune responses in mice. Immunization with rPrn also conferred protection against pertussis in mouse infection models. Our results indicated that the recombinant proteins still retain their immunological properties and highlighted the potential of the recombinant proteins for the future development of the B. pertussis vaccines.Pertussis or whooping cough is an infectious respiratory disease caused by the bacterium Bordetella pertussis. Despite being preventable by vaccination, pertussis remains one of the top ten causes of death worldwide in childhood, mainly in unvaccinated children [1]. According to the World Health Organization (WHO), about 17.6 million cases of pertussis occurred all over the world and about 279,000 patients died of pertussis in 2003 [2]. Most of deaths occurred in the developing countries.Immunization with whole cell pertussis vaccines (WPVs) was started in the middle of 20th Century and has significantly reduced the incidence of pertussis in many countries including China [3]. However, these WPVs have drawbacks in causing side e
Small Mutations in Bordetella pertussis Are Associated with Selective Sweeps  [PDF]
Marjolein van Gent, Marieke J. Bart, Han G. J. van der Heide, Kees J. Heuvelman, Frits R. Mooi
PLOS ONE , 2012, DOI: 10.1371/journal.pone.0046407
Abstract: Bordetella pertussis is the causative agent of pertussis, a highly contagious disease of the human respiratory tract. Despite high vaccination coverage, pertussis has resurged and has become one of the most prevalent vaccine-preventable diseases in developed countries. We have proposed that both waning immunity and pathogen adaptation have contributed to the persistence and resurgence of pertussis. Allelic variation has been found in virulence-associated genes coding for the pertussis toxin A subunit (ptxA), pertactin (prn), serotype 2 fimbriae (fim2), serotype 3 fimbriae (fim3) and the promoter for pertussis toxin (ptxP). In this study, we investigated how more than 60 years of vaccination has affected the Dutch B. pertussis population by combining data from phylogeny, genomics and temporal trends in strain frequencies. Our main focus was on the ptxA, prn, fim3 and ptxP genes. However, we also compared the genomes of 11 Dutch strains belonging to successful lineages. Our results showed that, between 1949 and 2010, the Dutch B. pertussis population has undergone as least four selective sweeps that were associated with small mutations in ptxA, prn, fim3 and ptxP. Phylogenetic analysis revealed a stepwise adaptation in which mutations accumulated clonally. Genomic analysis revealed a number of additional mutations which may have a contributed to the selective sweeps. Five large deletions were identified which were fixed in the pathogen population. However, only one was linked to a selective sweep. No evidence was found for a role of gene acquisition in pathogen adaptation. Our results suggest that the B. pertussis gene repertoire is already well adapted to its current niche and required only fine tuning to persist in the face of vaccination. Further, this work shows that small mutations, even single SNPs, can drive large changes in the populations of bacterial pathogens within a time span of six to 19 years.
Differentially Expressed Genes in Bordetella pertussis Strains Belonging to a Lineage Which Recently Spread Globally  [PDF]
Daan de Gouw, Peter W. M. Hermans, Hester J. Bootsma, Aldert Zomer, Kees Heuvelman, Dimitri A. Diavatopoulos, Frits R. Mooi
PLOS ONE , 2014, DOI: 10.1371/journal.pone.0084523
Abstract: Pertussis is a highly contagious, acute respiratory disease in humans caused by the Gram-negative pathogen Bordetella pertussis. Pertussis has resurged in the face of intensive vaccination and this has coincided with the emergence of strains carrying a particular allele for the pertussis toxin promoter, ptxP3, which is associated with higher levels of pertussis toxin (Ptx) production. Within 10 to 20 years, ptxP3 strains have nearly completely replaced the previously dominant ptxP1 strains resulting in a worldwide selective sweep. In order to identify B. pertussis genes associated with the selective sweep, we compared the expression of genes in ptxP1 and ptxP3 strains that are under control of the Bordetella master virulence regulatory locus (bvgASR). The BvgAS proteins comprise a two component sensory transduction system which is regulated by temperature, nicotinic acid and sulfate. By increasing the sulfate concentration, it is possible to change the phase of B. pertussis from virulent to avirulent. Until recently, the only distinctive phenotype of ptxP3 strains was a higher Ptx production. Here we identify additional phenotypic differences between ptxP1 and ptxP3 strains which may have contributed to its global spread by comparing global transcriptional responses under sulfate-modulating conditions. We show that ptxP3 strains are less sensitive to sulfate-mediated gene suppression, resulting in an increased production of the vaccine antigens pertactin (Prn) and Ptx and a number of other virulence genes, including a type III secretion toxin, Vag8, a protein involved in complement resistance, and lpxE involved in lipid A modification. Furthermore, enhanced expression of the vaccine antigens Ptx and Prn by ptxP3 strains was confirmed at the protein level. Identification of genes differentially expressed between ptxP1 and ptxP3 strains may elucidate how B. pertussis has adapted to vaccination and allow the improvement of pertussis vaccines by identifying novel vaccine candidates.
Infección por Bordetella pertussis
Archivos argentinos de pediatr?-a , 2010,
Abstract: physiopathological, clinical, and epidemiological aspects of whooping cough, an acute highly contagious respiratory infection caused by bordetella pertussis, are described. different vaccination schedules are mentioned, since the vaccine was introduced, more than 40 years ago, until present; and the outbreacks ocurred in argentina during different periods. moreover, the recrudescense of the disease observed in several countries during last years is highlighted, particularly in preschool children, and even more in adolescents, and young adults.
Genetic Analysis of Bordetella pertussis Isolates from the 2008–2010 Pertussis Epidemic in Japan  [PDF]
Yusuke Miyaji, Nao Otsuka, Hiromi Toyoizumi-Ajisaka, Keigo Shibayama, Kazunari Kamachi
PLOS ONE , 2013, DOI: 10.1371/journal.pone.0077165
Abstract: A large pertussis epidemic occurred between 2008 and 2010 in Japan. To investigate epidemic strains, we analyzed 33 Bordetella pertussis isolates from the epidemic period by sequencing virulence-associated genes (fim3, ptxP, ptxA, and prn) and performing multilocus variable-number tandem repeat analysis (MLVA), and compared these results with those of 101 isolates from non-epidemic, earlier and later time periods. DNA sequencing of the fim3 allele revealed that the frequency of fim3B was 4.3%, 12.8%, 30.3%, and 5.1% within isolates in 2002–2004, 2005–2007, 2008–2010, and 2011–2012, respectively. The isolation rate of the fim3B strain therefore temporarily increased during the epidemic period 2008–2010. In contrast, the frequencies of the virulence-associated allelic variants, ptxP3, ptxA1, and prn2, increased with time during overall study period, indicating that these variants were not directly involved in the occurrence of the 2008–2010 epidemic. MLVA genotyping in combination with analysis of allele types showed that the prevalence of an MT27d strain temporarily increased in the epidemic period, and that this strain carried virulence-associated allelic variants (fim3B, ptxP3, ptxA1, and prn2) also identified in recent epidemic strains of Australia, Europe, and the US. Phenotypic analyses revealed that the serotype Fim3 strain was predominant (≥87%) during all the periods studied, and that the frequency of adhesion pertactin (Prn) non-expressing B. pertussis decreased by half in the epidemic period. All MT27d strains expressed Prn and Fim3 proteins, suggesting that B. pertussis MT27d strains expressing Prn and Fim3B have the potential to cause large epidemics worldwide.
Seroepidemiology of Bordetella pertussis infections in the twin cities of Pakistan
Muhammad Ali Syed,Fahad Said,S. Habib Ali Bukhari
North American Journal of Medical Sciences , 2009,
Abstract: Background: Bordetella pertussis is the cause of whooping cough occurring mainly in children. The prevalence of this disease has been reduced largely due to worldwide mass vaccination with DTP vaccine. However, the immunity produced by the vaccination wanes by the passage of time. Still this disease kills around 2-4 million children annually. Adults may be a source of infection for infants and children. Furthermore, Bordetella pertussis has also been found to be associated with cases of persistent cough in adults in many countries. Aim: The aim of this study was to study the exposure of the adult population to the Bordetella pertussis by detecting IgG antibodies. Materials and Methods: We performed Seroepidemiology of Bordetella pertussis infections in multiethnic twin cities of Pakistan (Rawalpindi and Islamabad) using a commercially available ELISA kit to have a picture of epidemiology of Bordetella pertussis in Pakistan. We targeted adults of age between 18-45 years (mean age 29.64 years). Results: The results of our study show a high percentage of seropositivity to Bordetella pertussis (89 percent), which indicates higher exposure to this organism and risk of infection to infants, children, adolescents and adults. Conclusion: A high percentage of seropositive individuals are alarming to health care professionals as well as policy makers. Bordetella pertussis infections may be associated with their atypical manifestation in Pakistan. Adult vaccination with DTP is recommended to reduce the risk of infection in infants and children through adult reservoirs.
Epidemiological consequences of an ineffective Bordetella pertussis vaccine  [PDF]
Benjamin M. Althouse,Samuel V. Scarpino
Quantitative Biology , 2014,
Abstract: The recent increase in Bordetella pertussis incidence (whooping cough) presents a challenge to global health. Recent studies have called into question the effectiveness of acellular B. pertussis vaccination in reducing transmission. Here we examine the epidemiological consequences of an ineffective B. pertussis vaccine. Using a dynamic transmission model, we find that: 1) an ineffective vaccine can account for the observed increase in B. pertussis incidence; 2) asymptomatic infections can bias surveillance and upset situational awareness of B. pertussis; and 3) vaccinating individuals in close contact with infants too young to receive vaccine (so called "cocooning" unvaccinated children) may be ineffective. Our results have important implications for B. pertussis vaccination policy and paint a complicated picture for achieving herd immunity and possible B. pertussis eradication.
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