Probing the function of Bordetella bronchiseptica adenylate cyclase toxin by manipulating host immunity. (1/236)

We have examined the role of adenylate cyclase-hemolysin (CyaA) by constructing an in-frame deletion in the Bordetella bronchiseptica cyaA structural gene and comparing wild-type and cyaA deletion strains in natural host infection models. Both the wild-type strain RB50 and its adenylate cyclase toxin deletion (DeltacyaA) derivative efficiently establish persistent infections in rabbits, rats, and mice following low-dose inoculation. In contrast, an inoculation protocol that seeds the lower respiratory tract revealed significant differences in bacterial numbers and in polymorphonuclear neutrophil recruitment in the lungs from days 5 to 12 postinoculation. We next explored the effects of disarming specific aspects of the immune system on the relative phenotypes of wild-type and DeltacyaA bacteria. SCID, SCID-beige, or RAG-1(-/-) mice succumbed to lethal systemic infection following high- or low-dose intranasal inoculation with the wild-type strain but not the DeltacyaA mutant. Mice rendered neutropenic by treatment with cyclophosphamide or by knockout mutation in the granulocyte colony-stimulating factor locus were highly susceptible to lethal infection by either wild-type or DeltacyaA strains. These results reveal the significant role played by neutrophils early in B. bronchiseptica infection and by acquired immunity at later time points and suggest that phagocytic cells are a primary in vivo target of the Bordetella adenylate cyclase toxin.  (+info)

Evidence of efficacy of the Lederle/Takeda acellular pertussis component diphtheria and tetanus toxoids and pertussis vaccine but not the Lederle whole-cell component diphtheria and tetanus toxoids and pertussis vaccine against Bordetella parapertussis infection. (2/236)

A subanalysis of a recent cohort efficacy trial of a pertussis vaccine was performed to determine its efficacy against cough illnesses due to Bordetella parapertussis infections. Infants received four doses of either the Lederle/Takeda acellular pertussis component diphtheria and tetanus toxoids and pertussis (DTaP) vaccine or the Lederle whole-cell component diphtheria and tetanus toxoids and pertussis (DTP) vaccine at 3, 4.5, 6, and 15-18 months of age; controls received three doses of diphtheria and tetanus toxoids (DT) vaccine only. All subjects were prospectively followed for cough illnesses of > or = 7 days' duration; cases of B. parapertussis infection were confirmed by positive culture, household contact, or serology. Seventy-six cough illnesses due to B. parapertussis were identified; 24 occurred in 929 DTaP recipients, 37 in 937 DTP recipients, and 15 in 321 DT recipients, resulting in an efficacy of 50% for DTaP vaccine (95% CI [confidence interval], 5% to 74%) and 21% for DTP vaccine (95% CI, -45% to 56%). The data in the present analysis suggest that the Lederle/Takeda DTaP vaccine but not the Lederle whole-cell component DTP vaccine has efficacy against B. parapertussis infection.  (+info)

Outcomes of Bordetella infections in vaccinated children: effects of bacterial number in the nasopharynx and patient age. (3/236)

Five outbreaks of infection (three pertussis, one parapertussis, and one mixed) in schools were studied prospectively. Nasopharyngeal swabs were obtained from a total of 697 children for culture of Bordetella organisms. Of 50 vaccinated children with culture-confirmed Bordetella infections (29 with pertussis and 21 parapertussis), 40 were symptomatic and 10 remained symptom-free. Smaller numbers of colonies were recovered from the nasopharyngeal swabs of the asymptomatic children than from those of the symptomatic children. Older children had longer durations of illness than younger ones. Our results indicate that during outbreaks children who do not develop disease may have small amounts of Bordetella organisms in their nasopharynges and/or better immune defenses against the disease.  (+info)

Bordetella bronchiseptica infection in human immunodeficiency virus-infected patients. (4/236)

Bordetella bronchiseptica is a pleomorphic gram-negative coccobacillus that commonly causes respiratory tract infections in dogs. We identified nine human immunodeficiency virus (HIV)-infected persons with culture-confirmed B. bronchiseptica infections (eight respiratory tract and one disseminated infection). The respiratory illnesses ranged in severity from mild upper respiratory tract infection to pneumonia. All nine patients had had at least one AIDS-defining condition before the B. bronchiseptica infection. Two patients had household contact with dogs before their illnesses, and one had household contact with cats. Infection due to B. bronchiseptica is uncommon in HIV-infected persons. Additional data are needed to fully define the spectrum of disease due to B. bronchiseptica infections and to evaluate the possibility that this infection may be acquired from pets. Treatment of B. bronchiseptica infection should be tailored to the patient and should be based on the results of susceptibility testing.  (+info)

Parapertussis and pertussis: differences and similarities in incidence, clinical course, and antibody responses. (5/236)

OBJECTIVES: To compare the incidence, clinical course, and serologic response to Bordetella antigens in patients with parapertussis and pertussis. DESIGN: Two studies were performed in Sweden during the 1990s, when pertussis vaccines were used only in clinical trials. Study I was a retrospective study of patients with positive Bordetella cultures obtained in clinical routine, and study II involved an active search for patients with Bordetella infections during a placebo-controlled trial of a pertussis toxoid vaccine. RESULTS: Study I includes 58, and study II 23 patients with parapertussis. In study I, the incidence of parapertussis was 0.016 cases per 100 person years in children 0 to 6 years old and 0 in older children and adults. In study II, the incidence rates of parapertussis and pertussis were 0.2 and 16.2 per 100 person years, respectively, in children followed from 3 months to 3 years of age. The median number of days with cough was 21 in parapertussis and 59 in pertussis. The proportions of children with whooping and vomiting were lower in parapertussis than in pertussis. Geometric mean serum filamentous hemagglutinin IgG increased from 6 to 63, and pertactin IgG from 4 to 12 units/mL in parapertussis patients, which was similar to increases in children with pertussis. CONCLUSIONS: Disease caused by Bordetella parapertussis is diagnosed less commonly and is milder and of shorter duration than disease caused by Bordetella pertussis. Parapertussis induced serum IgG against filamentous hemagglutinin and pertactin of similar magnitude as does pertussis, and did not induce serum IgG against pertussis toxin.  (+info)

Pregenomic comparative analysis between bordetella bronchiseptica RB50 and Bordetella pertussis tohama I in murine models of respiratory tract infection. (6/236)

We describe here a side-by-side comparison of murine respiratory infection by Bordetella pertussis and Bordetella bronchiseptica strains whose genomes are currently being sequenced (Tohama I and RB50, respectively). B. pertussis and B. bronchiseptica are most appropriately classified as subspecies. Their high degree of genotypic and phenotypic relatedness facilitates comparative studies of pathogenesis. RB50 and Tohama I differ in their abilities to grow in the nose, trachea, and lungs of BALB/c mice and to induce apoptosis, lung pathology, and an antibody response. To focus on the interactions between the bacteria and particular aspects of the host immune response, we used mice with specific immune defects. Mice lacking B cells and T cells were highly susceptible to B. bronchiseptica and were killed by intranasal inoculation with doses as low as 500 CFU. These mice were not killed by B. pertussis, even when doses as high as 10(5) CFU were delivered to the lungs. B. bronchiseptica, which was highly resistant to naive serum in vitro, caused bacteremia in these immunodeficient mice, while B. pertussis, which was highly sensitive to naive serum, did not cause bacteremia. B. bronchiseptica was, however, killed by immune serum in vitro, and adoptive transfer of anti-Bordetella antibodies protected SCID-beige mice from B. bronchiseptica lethal infection. Neutropenic mice were similarly killed by B. bronchiseptica but not B. pertussis infection, suggesting neutrophils are critical to the early inflammatory response to the former but not the latter. B. bronchiseptica was dramatically more active than B. pertussis in mediating the lysis of J774 cells in vitro and in inducing apoptosis of inflammatory cells in mouse lungs. This side-by-side comparison describes phenotypic differences that may be correlated with genetic differences in the comparative analysis of the genomes of these two highly related organisms.  (+info)

Polymorphism in the pertussis toxin promoter region affecting the DNA-based diagnosis of Bordetella infection. (7/236)

The pertussis toxin (PT) promoter region is a frequently used target for DNA-based diagnosis of pertussis and parapertussis infections. The reported polymorphism in this region has also allowed discrimination of species in mixtures with several Bordetella species by their specific PCR amplicon restriction patterns. In the present study, we investigated the degree of polymorphism in order to confirm the reliability of the assay. Five different sequence types of the amplified 239- or 249-bp region were found among the 33 Bordetella pertussis, B. parapertussis, and B. bronchiseptica American Type Culture Collection reference strains and patient isolates analyzed. According to the sequences that were obtained and according to the PT promoter sequences already available in the databases, restriction enzyme analysis with TaqI, BglI, and HaeII, which gave four different patterns, can be performed to reliably identify B. pertussis, B. parapertussis, and B. bronchiseptica.  (+info)

Biological activities of lipopolysaccharides extracted from porcine vaccine strains. (8/236)

Lipopolysaccharides (LPSs) were purified from Actinobacillus pleuropneumoniae serotype 2, Bordetella bronchiseptica and Haemophilus parasuis serotype 5, which were used for vaccine production in Japan, by the phenol-water procedure. In SDS-PAGE analysis, A. pleuropneumoniae LPS, as well as Escherichia coli LPS, demonstrated a typical ladder profile of a smooth-type LPS. On the other hand, B. bronchiseptica and H. parasuis LPSs lacked the ladder profiles. It was found that the biological activity of these LPSs was comparable to those of E. coli LPS in terms of activation of the clotting enzyme of Limulus amoebocyte lysate, mitogenic activity of mouse spleen cells, stimulation of TNF-alpha and nitric oxide production, but IL-6 production could hardly be observed in any LPS.  (+info)

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