RESUMO
Bordetella bronchiseptica is a pathogen causing respiratory infections in mammals. With the improving understanding of companion animals' welfare, addressing the side effects of bordetella vaccine gains importance in dogs. Studies on diverse subunit vaccines are actively pursued in humans to safely and effectively control bordetellosis. Therefore, our objective was to develop a canine bordetella vaccine inspired by human vaccine development. We evaluated the immunogenicity of the two bacterial components: the outer membrane proteins (OMPs) and the dermonecrotic toxin (DNT) from a canine isolate of B. bronchiseptica. In-silico analysis identified eight domains of DNT, and Domain 3 was selected as the most promising antigen candidate. Additionally, the OMPs were extracted and examined using SDS-PAGE and Western blot analysis. The distinct immunological characteristic of OMPs and DNT-3 were examined individually and in combination. Gene expression and cytokine production were also evaluated in DH82 cells after stimulation with those antigens. Treatment with OMPs resulted in higher level of Th1 related cytokines, while DNT-3 induced a predominant response associated with Th17 and Th2 in the cytokine production. Synergistic effects were observed exclusively on IL-23, indicating increase of a potential risk of side effects when OMPs and DNT act together. These findings provide valuable insights into the reactogenicity of conventional Bordetella vaccines. Further, the presented preclinical data in this study offer an alternative method of the development for an optimal next-generation Bordetella vaccine for companion animals and humans, replacing the acellular vaccines containing both toxin and protein components.
Assuntos
Proteínas da Membrana Bacteriana Externa , Infecções por Bordetella , Bordetella bronchiseptica , Doenças do Cão , Bordetella bronchiseptica/imunologia , Animais , Cães , Proteínas da Membrana Bacteriana Externa/imunologia , Infecções por Bordetella/imunologia , Infecções por Bordetella/veterinária , Infecções por Bordetella/microbiologia , Infecções por Bordetella/prevenção & controle , Doenças do Cão/imunologia , Doenças do Cão/microbiologia , Vacinas Bacterianas/imunologia , Citocinas/imunologia , Fatores de Virulência de Bordetella/imunologia , TransglutaminasesRESUMO
Bordetella infection can be efficiently prevented through vaccination. The current study investigated the effects of an extract of Cochinchina momordica seed (ECMS) combined with oil on the immune responses to the inactivated Bordetella vaccine in mice. Serum IgG and IgG1 level was significantly increased in ECMS-oil group compared to any other group (P < 0.05) 2 weeks after immunization, while groups ECMS200 µg/400 µg-oil had a markedly higher level of serum IgG2b and IgG3 than any other groups (P < 0.05). Moreover, lipopolysaccharide/ConA-stimulated proliferation of splenocytes was significantly enhanced in ECMS 400 µg-oil immunized mice in comparison with mice in any other group (P < 0.05). RT-PCR assay revealed that while ECMS800 µg-oil group had significantly higher levels of serum IL-4, IL-10, Toll-like receptor (TLR)2, and IL-1 beta than any other group (P < 0.05), the levels of serum IL-2, IL-4, and IL-10 were markedly increased in ECMS 400 µg-oil group as compared to any other groups (P < 0.05). Blood analysis showed that ECMS800 µg-oil and oil groups had a significantly higher number of immunocytes than any other groups (P < 0.05). There were significant differences in the number of IgG+, IgG2b+, and IgA+ cells in the lung between ECMS800 µg-oil group and any other groups (P < 0.05). Western blot analysis demonstrated that stimulation with ECMS 25 µg/mL or 50 ng/mL led to a significant increase in the expression of TLR2, MyD88, and NF-κB in Raw264.7 cells (P < 0.05). Compared with any other group, the expression of MyD88 was markedly increased in the cells stimulated with ECMS 50 ng/mL, as indicated by the RT-PCR analysis (P < 0.05). Overall, we observed that ECMS-oil efficiently enhanced the humoral or cellular immune responses against Bordetella and suggested that the mechanism of adjuvant activity of ECMS-oil might involve TLR2/MyD88/NF-κB signaling pathway.
Assuntos
Infecções por Bordetella , Bordetella bronchiseptica , Momordica , Animais , Camundongos , Adjuvantes Imunológicos/farmacologia , Bordetella bronchiseptica/efeitos dos fármacos , Imunidade , Imunoglobulina G/metabolismo , Interleucina-10/metabolismo , Interleucina-4/metabolismo , Momordica/química , Fator 88 de Diferenciação Mieloide/genética , Fator 88 de Diferenciação Mieloide/metabolismo , NF-kappa B/metabolismo , Sementes/química , Receptor 2 Toll-Like/genética , Receptor 2 Toll-Like/metabolismo , Infecções por Bordetella/tratamento farmacológico , Infecções por Bordetella/imunologiaRESUMO
Eosinophils are granulocytes primarily associated with TH2 responses to parasites or immune hyper-reactive states, such as asthma, allergies, or eosinophilic esophagitis. However, it does not make sense from an evolutionary standpoint to maintain a cell type that is only specific for parasitic infections and that otherwise is somehow harmful to the host. In recent years, there has been a shift in the perception of these cells. Eosinophils have recently been recognized as regulators of immune homeostasis and suppressors of over-reactive pro-inflammatory responses by secreting specific molecules that dampen the immune response. Their role during parasitic infections has been well investigated, and their versatility during immune responses to helminths includes antigen presentation as well as modulation of T cell responses. Although it is known that eosinophils can present antigens during viral infections, there are still many mechanistic aspects of the involvement of eosinophils during viral infections that remain to be elucidated. However, are eosinophils able to respond to bacterial infections? Recent literature indicates that Helicobacter pylori triggers TH2 responses mediated by eosinophils; this promotes anti-inflammatory responses that might be involved in the long-term persistent infection caused by this pathogen. Apparently and on the contrary, in the respiratory tract, eosinophils promote TH17 pro-inflammatory responses during Bordetella bronchiseptica infection, and they are, in fact, critical for early clearance of bacteria from the respiratory tract. However, eosinophils are also intertwined with microbiota, and up to now, it is not clear if microbiota regulates eosinophils or vice versa, or how this connection influences immune responses. In this review, we highlight the current knowledge of eosinophils as regulators of pro and anti-inflammatory responses in the context of both infection and naïve conditions. We propose questions and future directions that might open novel research avenues in the future.
Assuntos
Infecções por Bordetella/imunologia , Bordetella bronchiseptica/imunologia , Eosinófilos/imunologia , Infecções por Helicobacter/imunologia , Helicobacter pylori/imunologia , Microbiota/imunologia , Animais , Humanos , Células Th17/imunologia , Células Th2/imunologiaRESUMO
Type I and III IFNs play diverse roles in bacterial infections, being protective for some but deleterious for others. Using RNA-sequencing transcriptomics we investigated lung gene expression responses to Bordetella pertussis infection in adult mice, revealing that type I and III IFN pathways may play an important role in promoting inflammatory responses. In B. pertussis-infected mice, lung type I/III IFN responses correlated with increased proinflammatory cytokine expression and with lung inflammatory pathology. In mutant mice with increased type I IFN receptor (IFNAR) signaling, B. pertussis infection exacerbated lung inflammatory pathology, whereas knockout mice with defects in type I IFN signaling had lower levels of lung inflammation than wild-type mice. Curiously, B. pertussis-infected IFNAR1 knockout mice had wild-type levels of lung inflammatory pathology. However, in response to infection these mice had increased levels of type III IFN expression, neutralization of which reduced lung inflammation. In support of this finding, B. pertussis-infected mice with a knockout mutation in the type III IFN receptor (IFNLR1) and double IFNAR1/IFNLR1 knockout mutant mice had reduced lung inflammatory pathology compared with that in wild-type mice, indicating that type III IFN exacerbates lung inflammation. In marked contrast, infant mice did not upregulate type I or III IFNs in response to B. pertussis infection and were protected from lethal infection by increased type I IFN signaling. These results indicate age-dependent effects of type I/III IFN signaling during B. pertussis infection and suggest that these pathways represent targets for therapeutic intervention in pertussis.
Assuntos
Infecções por Bordetella/imunologia , Bordetella pertussis/imunologia , Interferon Tipo I/imunologia , Interferons/imunologia , Infecções Respiratórias/imunologia , Fatores Etários , Animais , Infecções por Bordetella/genética , Bordetella pertussis/patogenicidade , Feminino , Interferon Tipo I/genética , Interferons/genética , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Camundongos Transgênicos , Mutação , Receptores de Interferon/deficiência , Receptores de Interferon/genética , Receptores de Interferon/imunologia , Infecções Respiratórias/genética , Análise de Sequência de RNA , Transdução de Sinais/genética , Transdução de Sinais/imunologia , Transcriptoma , Interferon lambdaRESUMO
AIMS: The outer membrane porin protein (OMPP) of Bordetella bronchiseptica is an important adhesion factor and protective immunogen. The aim of this study was to verify the immunogenicity of recombinant OMPP and its protective efficacy against a lethal challenge with B. bronchiseptica in rabbits. METHODS AND RESULTS: Soluble rOMPP was successfully expressed in Escherichia coli, and the purified recombinant protein was mixed with the ISA 201 VG adjuvant to prepare a subunit vaccine for B. bronchiseptica. Rabbits were immunized with the rOMPP subunit vaccine and then infected with the virulent B. bronchiseptica strain QDBb01. Rabbits immunized with the subunit vaccine were completely protected compared to the control group, and the protective effect was obviously better than that of the inactivated whole-cell vaccine. Moreover, analysis of the immunization duration showed that the rOMPP subunit vaccine provided immune protection for at least 4 months after the second immunization. CONCLUSIONS: The rOMPP subunit vaccine completely protected rabbits from a subsequent B. bronchiseptica challenge. SIGNIFICANCE AND IMPACT OF THE STUDY: The results will provide key information for the development of a safe and effective recombinant subunit vaccine against B. bronchiseptica in rabbits.
Assuntos
Vacinas Bacterianas/imunologia , Infecções por Bordetella/prevenção & controle , Bordetella bronchiseptica/imunologia , Porinas/imunologia , Adjuvantes Imunológicos , Animais , Vacinas Bacterianas/administração & dosagem , Vacinas Bacterianas/isolamento & purificação , Infecções por Bordetella/imunologia , Bordetella bronchiseptica/patogenicidade , Imunização , Porinas/genética , Porinas/isolamento & purificação , Porinas/metabolismo , Coelhos , Proteínas Recombinantes/genética , Proteínas Recombinantes/imunologia , Proteínas Recombinantes/isolamento & purificação , Proteínas Recombinantes/metabolismo , Vacinas de Subunidades AntigênicasRESUMO
The Bordetella species are Gram-negative bacterial pathogens that colonizes mammalian respiratory tract causing respiratory diseases in humans and animals. B. bronchiseptica causes clinical conditions in many mammals including immunocompromised humans. Using the dog model of respiratory infection, it has been shown in this study that a newly developed B. bronchiseptica Bacterial Ghost (BbBG) vaccine exhibited significant protection in the face of a severe pathogenic bacterial challenge in seronegative dogs. The protein E-specific lysis mechanism was used to produce BbBGs. Bacterial Ghosts (BGs) are the empty cell envelope of Gram-negative bacterium. They are genetically processed to form a microscopic hole in their membrane, through which all the cytoplasmic contents are expelled leaving behind intact empty bacterial shells. Due to the intact surface structures of BGs, they offer the safety of inactivated but efficacy of live attenuated vaccines. In this study, seronegative dogs were vaccinated subcutaneously (s/c) with two different doses of a newly developed BbBG vaccine [lower 10â§5 (BbBG - 5) and higher 10â§7 (BbBG - 7)] on day 0 and 21. The animals were challenged (by aerosol) with virulent live B. bronchiseptica strains 41 days after first vaccination. The dogs vaccinated s/c with BbBG - 7 vaccine had significantly lower spontaneous coughing scores (P = 0.0001) than dogs in negative control group. Furthermore, the tested BbBG - 7 vaccine was equivalent to the positive control vaccine Bronchicine CAe in terms of safety and efficacy. For the first time, we report the successful use of liquid formulated BGs vaccines in animal studies. Earlier reported studies using BGs vaccines were performed with resuspended freeze-dried BGs preparations.
Assuntos
Vacinas Bacterianas/farmacologia , Infecções por Bordetella/prevenção & controle , Bordetella bronchiseptica/imunologia , Infecções Respiratórias/prevenção & controle , Animais , Vacinas Bacterianas/imunologia , Infecções por Bordetella/imunologia , Infecções por Bordetella/patologia , Modelos Animais de Doenças , Cães , Relação Dose-Resposta Imunológica , Humanos , Injeções Subcutâneas , Infecções Respiratórias/imunologia , Infecções Respiratórias/patologiaRESUMO
Bordetella bronchiseptica is an etiologic agent of respiratory diseases in animals and humans. Despite the widespread use of veterinary B. bronchiseptica vaccines, there is limited information on their composition and relative efficacy and on the immune responses that they elicit. Furthermore, human B. bronchiseptica vaccines are not available. We leveraged the dual antigenic and adjuvant functions of Bordetella colonization factor A (BcfA) to develop acellular B. bronchiseptica vaccines in the absence of an additional adjuvant. BALB/c mice immunized with BcfA alone or a trivalent vaccine containing BcfA and the Bordetella antigens FHA and Prn were equally protected against challenge with a prototype B. bronchiseptica strain. The trivalent vaccine protected mice significantly better than the canine vaccine Bronchicine and provided protection against a B. bronchiseptica strain isolated from a dog with kennel cough. Th1/17-polarized immune responses correlate with long-lasting protection against bordetellae and other respiratory pathogens. Notably, BcfA strongly attenuated the Th2 responses elicited by FHA and Prn, resulting in Th1/17-skewed responses in inherently Th2-skewed BALB/c mice. Thus, BcfA functions as both an antigen and an adjuvant, providing protection as a single-component vaccine. BcfA-adjuvanted vaccines may improve the efficacy and durability of vaccines against bordetellae and other pathogens.
Assuntos
Adesinas Bacterianas/administração & dosagem , Adjuvantes Imunológicos/administração & dosagem , Antígenos de Bactérias/administração & dosagem , Proteínas da Membrana Bacteriana Externa/administração & dosagem , Vacinas Bacterianas/administração & dosagem , Infecções por Bordetella/prevenção & controle , Bordetella bronchiseptica/efeitos dos fármacos , Fatores de Virulência de Bordetella/administração & dosagem , Animais , Infecções por Bordetella/imunologia , Infecções por Bordetella/microbiologia , Bordetella bronchiseptica/imunologia , Bordetella bronchiseptica/patogenicidade , Cães , Feminino , Humanos , Imunização , Imunogenicidade da Vacina , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Células Th1/efeitos dos fármacos , Células Th1/imunologia , Células Th1/microbiologia , Equilíbrio Th1-Th2/efeitos dos fármacos , Células Th17/efeitos dos fármacos , Células Th17/imunologia , Células Th17/microbiologia , Células Th2/efeitos dos fármacos , Células Th2/imunologia , Células Th2/microbiologiaRESUMO
The mammalian immune system includes a sophisticated array of antimicrobial mechanisms. However, successful pathogens have developed subversive strategies to detect, modulate, and/or evade immune control and clearance. Independent disciplines study host immunology and bacterial pathogenesis, but interkingdom signaling between bacteria and host during natural infection remains poorly understood. An efficient natural host infection system has revealed complex communication between Bordetella spp. and mice, identified novel regulatory mechanisms, and demonstrated that bordetellae can respond to microenvironment and inflammatory status cues. Understanding these bacterial signaling pathways and their complex network that allows precisely timed expression of numerous immunomodulatory factors will serve as a paradigm for other organisms lacking such a powerful experimental infection system. VIDEO ABSTRACT.
Assuntos
Infecções por Bordetella/imunologia , Infecções por Bordetella/transmissão , Bordetella/imunologia , Interações Hospedeiro-Patógeno/imunologia , Interações Hospedeiro-Patógeno/fisiologia , Imunomodulação , Transdução de Sinais , Animais , Proteínas de Bactérias/metabolismo , Microambiente Celular/imunologia , Meio Ambiente , Humanos , Imunidade Inata/imunologia , Inflamação , Camundongos , Virulência , Fatores de Virulência/imunologiaRESUMO
Well-adapted pathogens must evade clearance by the host immune system and the study of how they do this has revealed myriad complex strategies and mechanisms. Classical bordetellae are very closely related subspecies that are known to modulate adaptive immunity in a variety of ways, permitting them to either persist for life or repeatedly infect the same host. Exploring the hypothesis that exposure to immune cells would cause bordetellae to induce expression of important immunomodulatory mechanisms, we identified a putative regulator of an immunomodulatory pathway. The deletion of btrS in B. bronchiseptica did not affect colonization or initial growth in the respiratory tract of mice, its natural host, but did increase activation of the inflammasome pathway, and recruitment of inflammatory cells. The mutant lacking btrS recruited many more B and T cells into the lungs, where they rapidly formed highly organized and distinctive Bronchial Associated Lymphoid Tissue (BALT) not induced by any wild type Bordetella species, and a much more rapid and strong antibody response than observed with any of these species. Immunity induced by the mutant was measurably more robust in all respiratory organs, providing completely sterilizing immunity that protected against challenge infections for many months. Moreover, the mutant induced sterilizing immunity against infection with other classical bordetellae, including B. pertussis and B. parapertussis, something the current vaccines do not provide. These findings reveal profound immunomodulation by bordetellae and demonstrate that by disrupting it much more robust protective immunity can be generated, providing a pathway to greatly improve vaccines and preventive treatments against these important pathogens.
Assuntos
Imunidade Adaptativa/fisiologia , Infecções por Bordetella/imunologia , Bordetella/imunologia , Imunomodulação/fisiologia , Infecções Respiratórias/imunologia , Animais , Anticorpos Antibacterianos/imunologia , CamundongosRESUMO
Well-adapted pathogens have evolved to survive the many challenges of a robust immune response. Defending against all host antimicrobials simultaneously would be exceedingly difficult, if not impossible, so many co-evolved organisms utilize immunomodulatory tools to subvert, distract, and/or evade the host immune response. Bordetella spp. present many examples of the diversity of immunomodulators and an exceptional experimental system in which to study them. Recent advances in this experimental system suggest strategies for interventions that tweak immunity to disrupt bacterial immunomodulation, engaging more effective host immunity to better prevent and treat infections. Here we review advances in the understanding of respiratory pathogens, with special focus on Bordetella spp., and prospects for the use of immune-stimulatory interventions in the prevention and treatment of infection.
Assuntos
Infecções por Bordetella/imunologia , Infecções por Bordetella/prevenção & controle , Bordetella/imunologia , Infecções por Bordetella/patologia , HumanosRESUMO
Bordetella parapertussis is a respiratory-disease pathogen producing symptomatology similar to that of pertussis but of underestimated incidence and with no specific vaccine existing. We recently designed a vaccine candidate from B. parapertussis outer-membrane vesicles (OMVs) that proved to be safe and protective in a murine-infection model. Based on protection recently reported for the B. parapertussis O antigen in aqueous solution, we assessed here whether the B. parapertussis O-antigen-containing lipopolysaccharide (BppLPS-O+) embedded in the membranes, as present in B. parapertussis-derived OMVs (OMVs(Bpp-LPS-O+)), was the component responsible for that previously observed protection by OMVs. By performing a comparative study with OMVs from a human strain with undetectable O antigen (OMVs(Bpp-LPS-O-)), we demonstrated that the OMVs(Bpp-LPS-O+), but not the OMVs(Bpp-LPS-O-), protected mice against sublethal B. parapertussis infections. Indeed, the B. parapertussis loads were significantly reduced in the lungs of OMVs(Bpp-LPS-O+) -vaccinated animals, with the CFUs recovered being decreased by 4 log units below those detected in the non-immunized animals or in the animals treated with the OMVs(Bpp-LPS-O-), (p < 0.001). We detected that the OMVs(Bpp-LPS-O+) induced IgG antibodies against B. parapertussis whole-cell lysates, which immunocomponents recognized, among others, the O antigen and accordingly conferred protection against B. parapertussis infection, as observed in in-vivo-passive-transfer experiments. Of interest was that the OMVs(Bpp-LPS-O+) -generated sera had opsonophagocytic and bactericidal capabilities that were not detected with the OMVs(Bpp-LPS-O-)-induced sera, suggesting that those activities were involved in the clearance of B. parapertussis. Though stimulation of cultured spleen cells from immunized mice with formulations containing the O antigen resulted in gamma interferon (IFN-γ) and interleukin-17 production, spleen cells from OMVs(Bpp-LPS-O+) -immunized mice did not significantly contribute to the observed protection against B. parapertussis infection. The protective capability of the B. parapertussis O antigen was also detected in formulations containing both the OMVs derived from B. pertussis and purified BppLPS-O+. This combined formulation protected mice against B. pertussis along with B. parapertussis.
Assuntos
Vacinas Bacterianas/imunologia , Infecções por Bordetella/imunologia , Bordetella parapertussis/fisiologia , Bordetella pertussis/fisiologia , Antígenos O/imunologia , Animais , Anticorpos Antibacterianos/sangue , Proteínas da Membrana Bacteriana Externa/metabolismo , Micropartículas Derivadas de Células/metabolismo , Resistência à Doença , Feminino , Humanos , Imunidade Heteróloga , Imunização Passiva , Interferon gama/metabolismo , Interleucina-17/metabolismo , Ativação Linfocitária , Camundongos , Camundongos Endogâmicos BALB C , Antígenos O/metabolismo , VacinaçãoRESUMO
The respiratory tract is constantly exposed to the environment and displays a favorable niche for colonizing microorganisms. However, the effects of respiratory bacterial carriage on the immune system and its implications for secondary responses remain largely unclear. We have employed respiratory carriage with Bordetella bronchiseptica as the underlying model to comprehensively address effects on subsequent immune responses. Carriage was associated with the stimulation of Bordetella-specific CD4âº, CD8âº, and CD4âºCD25âºFoxp3⺠T cell responses, and broad transcriptional activation was observed in CD4âºCD25⺠T cells. Importantly, transfer of leukocytes from carriers to acutely B. bronchiseptica infected mice, resulted in a significantly increased bacterial burden in the recipient's upper respiratory tract. In contrast, we found that respiratory B. bronchiseptica carriage resulted in a significant benefit for the host in systemic infection with Listeria monocytogenes. Adaptive responses to vaccination and influenza A virus infection, were unaffected by B. bronchiseptica carriage. These data showed that there were significant immune modulatory processes triggered by B. bronchiseptica carriage, that differentially affect subsequent immune responses. Therefore, our results demonstrated the complexity of immune regulation induced by respiratory bacterial carriage, which can be beneficial or detrimental to the host, depending on the pathogen and the considered compartment.
Assuntos
Bordetella bronchiseptica/imunologia , Coinfecção/imunologia , Infecções Respiratórias/imunologia , Linfócitos T Reguladores/microbiologia , Vacinação , Imunidade Adaptativa/imunologia , Animais , Anticorpos Antibacterianos/sangue , Anticorpos Antibacterianos/imunologia , Infecções por Bordetella/sangue , Infecções por Bordetella/imunologia , Infecções por Bordetella/microbiologia , Infecções por Bordetella/prevenção & controle , Bordetella bronchiseptica/genética , Antígenos CD5/análise , Portador Sadio/imunologia , Portador Sadio/microbiologia , Coinfecção/sangue , Coinfecção/microbiologia , Coinfecção/prevenção & controle , Vírus da Influenza A/genética , Vírus da Influenza A/imunologia , Listeria monocytogenes/genética , Listeria monocytogenes/imunologia , Camundongos , Camundongos Endogâmicos BALB C , Infecções Respiratórias/sangue , Infecções Respiratórias/prevenção & controle , Linfócitos T Reguladores/imunologiaAssuntos
Bacteriemia/microbiologia , Infecções por Bordetella/diagnóstico , Bordetella , Hospedeiro Imunocomprometido , Idoso , Alcaligenes faecalis/isolamento & purificação , Bacteriemia/diagnóstico , Bacteriemia/tratamento farmacológico , Bacteriemia/imunologia , Bordetella/isolamento & purificação , Infecções por Bordetella/tratamento farmacológico , Infecções por Bordetella/imunologia , Neoplasias da Mama/complicações , Neoplasias da Mama/imunologia , Neoplasias da Mama/patologia , Infecções Relacionadas a Cateter/diagnóstico , Infecções Relacionadas a Cateter/tratamento farmacológico , Infecções Relacionadas a Cateter/imunologia , Infecções Relacionadas a Cateter/microbiologia , Coinfecção , Feminino , Infecções por Bactérias Gram-Negativas/complicações , Infecções por Bactérias Gram-Negativas/diagnóstico , Infecções por Bactérias Gram-Negativas/tratamento farmacológico , Infecções por Bactérias Gram-Negativas/imunologia , Humanos , Metástase Neoplásica , Combinação Piperacilina e Tazobactam/uso terapêuticoRESUMO
Bordetella bronchiseptica, a Gram-negative bacterium, causes chronic respiratory tract infections in a wide variety of mammalian hosts, including humans (albeit rarely). We recently designed Bordetella pertussis and Bordetella parapertussis experimental vaccines based on outer membrane vesicles (OMVs) derived from each pathogen, and we obtained protection against the respective infections in mice. Here, we demonstrated that OMVs derived from virulent-phase B. bronchiseptica (OMVBbvir+) protected mice against sublethal infections with different B. bronchiseptica strains, two isolated from farm animals and one isolated from a human patient. In all infections, we observed that the B. bronchiseptica loads were significantly reduced in the lungs of vaccinated animals; the lung-recovered CFU were decreased by ≥4 log units, compared with those detected in the lungs of nonimmunized animals (P < 0.001). In the OMVBbvir+-immunized mice, we detected IgG antibody titers against B. bronchiseptica whole-cell lysates, along with an immune serum having bacterial killing activity that both recognized B. bronchiseptica lipopolysaccharides and polypeptides such as GroEL and outer membrane protein C (OMPc) and demonstrated an essential protective capacity against B. bronchiseptica infection, as detected by passive in vivo transfer experiments. Stimulation of cultured splenocytes from immunized mice with OMVBbvir+ resulted in interleukin 5 (IL-5), gamma interferon (IFN-γ), and IL-17 production, indicating that the vesicles induced mixed Th2, Th1, and Th17 T-cell immune responses. We detected, by adoptive transfer assays, that spleen cells from OMVBbvir+-immunized mice also contributed to the observed protection against B. bronchiseptica infection. OMVs from avirulent-phase B. bronchiseptica and the resulting induced immune sera were also able to protect mice against B. bronchiseptica infection.IMPORTANCEBordetella bronchiseptica, a Gram-negative bacterium, causes chronic respiratory tract infections in a wide variety of mammalian hosts, including humans (albeit rarely). Several vaccines aimed at preventing B. bronchiseptica infection have been developed and used, but a safe effective vaccine is still needed. The significance and relevance of our research lie in the characterization of the OMVs derived from B. bronchiseptica as the source of a new experimental vaccine. We demonstrated here that our formulation based on OMVs derived from virulent-phase B. bronchiseptica (OMVBbvir+) was effective against infections caused by B. bronchiseptica isolates obtained from different hosts (farm animals and a human patient). In vitro and in vivo characterization of humoral and cellular immune responses induced by the OMVBbvir+ vaccine enabled a better understanding of the mechanism of protection necessary to control B. bronchiseptica infection. Here we also demonstrated that OMVs derived from B. bronchiseptica in the avirulent phase and the corresponding induced humoral immune response were able to protect mice from B. bronchiseptica infection. This realization provides the basis for the development of novel vaccines not only against the acute stages of the disease but also against stages of the disease or the infectious cycle in which avirulence factors could play a role.
Assuntos
Proteínas da Membrana Bacteriana Externa/imunologia , Vacinas Bacterianas/imunologia , Infecções por Bordetella/prevenção & controle , Bordetella bronchiseptica/citologia , Bordetella bronchiseptica/patogenicidade , Animais , Anticorpos Antibacterianos/sangue , Vacinas Bacterianas/administração & dosagem , Infecções por Bordetella/imunologia , Infecções por Bordetella/microbiologia , Bordetella bronchiseptica/química , Bordetella bronchiseptica/imunologia , Feminino , Humanos , Imunidade Celular , Imunidade Humoral , Imunização , Camundongos , Camundongos Endogâmicos BALB C , Fenótipo , Infecções Respiratórias/imunologia , Infecções Respiratórias/microbiologia , Infecções Respiratórias/prevenção & controle , Células Th17/imunologia , VirulênciaRESUMO
BACKGROUND: Increasing incidence of whooping cough (pertussis) has been reported in many countries, attributed to a switch from whole-cell pertussis-containing vaccine (wPV) to acellular PV (aPV) and circulation of the pertactin non-producing Bordetella pertussis. The present study aimed to estimate the duration of immunity conferred by PVs in children in France with data from an ongoing pediatric ambulatory surveillance of pertussis. METHODS: A total of 64 pediatricians throughout France enrolled children with suspected pertussis. A standardized data form was used to collect data on age sex, vaccination status, brand of wPV or aPV and source of infection. Confirmed cases were positive on culture and/or real-time Polymerase Chain Reaction (for B.-non-classified or B. pertussis or B. parapertussis) and/or pertussis serology. RESULTS: Between October 2006 and December 2015, 149 cases of confirmed Bordetella infections were reported, 86 infected with B. pertussis and 55 B. non-classified. Fifteen children (10.1%) were not vaccinated, and 26 (17.4%) were partially vaccinated. The mean age was greater for children who received 4 doses of wPV (11.3±2.2, p<0.001) or a combination of wPV and aPV (10.5±3.3, p<0.001) than only aPV (7.2±2.4years). The mean duration of cough before a visit to a pediatrician was longer for children with wPV or a combination of wPV and aPV than only aPV (23.8±10.1 and 25.0±25.6vs 13.6±10.0days). CONCLUSION: Despite the use of a more sensitive diagnostic method and emergence of pertactin non producing B. pertussis, in France context, aPV-induced immunity still protects against pertussis; however, the mean duration of immunity is about 6 to 7years, compared to 9years for wPV vaccine, after the primary vaccination and one booster (3+1 doses).
Assuntos
Coqueluche/imunologia , Coqueluche/prevenção & controle , Adulto , Proteínas da Membrana Bacteriana Externa/imunologia , Infecções por Bordetella/imunologia , Bordetella pertussis/imunologia , Criança , Pré-Escolar , Feminino , França , Humanos , Imunização/métodos , Incidência , Masculino , Pessoa de Meia-Idade , Vacina contra Coqueluche/imunologia , Prática Privada , Fatores de Virulência de Bordetella/imunologiaRESUMO
Whooping cough, which is caused by Bordetella pertussis and B. parapertussis, is a reemerging disease. New protective antigens are needed to improve the efficacy of current vaccines against both species. Using proteomic tools, it was here found that B. parapertussis expresses a homolog of AfuA, a previously reported new vaccine candidate against B. pertussis. It was found that this homolog, named AfuABpp , is expressed during B. parapertussis infection, exposed on the surface of the bacteria and recognized by specific antibodies induced by the recombinant AfuA cloned from B. pertussis (rAfuA). Importantly, the presence of the O-antigen, a molecule that has been found to shield surface antigens on B. parapertussis, showed no influence on antibody recognition of AfuABpp on the bacterial surface. The present study further showed that antibodies induced by immunization with the recombinant protein were able to opsonize B. parapertussis and promote bacterial uptake by neutrophils. Finally, it was shown that this antigen confers protection against B. parapertussis infection in a mouse model. Altogether, these results indicate that AfuA is a good vaccine candidate for acellular vaccines protective against both causative agents of whooping cough.
Assuntos
Antígenos de Bactérias/genética , Antígenos de Bactérias/imunologia , Proteínas da Membrana Bacteriana Externa/genética , Proteínas da Membrana Bacteriana Externa/imunologia , Infecções por Bordetella/prevenção & controle , Bordetella parapertussis/efeitos dos fármacos , Bordetella pertussis/genética , Vacina contra Coqueluche/imunologia , Proteínas Recombinantes/genética , Proteínas Recombinantes/imunologia , Animais , Anticorpos Antibacterianos/imunologia , Proteínas de Bactérias/genética , Proteínas de Bactérias/imunologia , Infecções por Bordetella/imunologia , Bordetella parapertussis/imunologia , Bordetella parapertussis/patogenicidade , Bordetella pertussis/efeitos dos fármacos , Bordetella pertussis/imunologia , Bordetella pertussis/metabolismo , Modelos Animais de Doenças , Feminino , Imunização , Camundongos , Camundongos Endogâmicos BALB C , Neutrófilos/imunologia , Antígenos O/imunologia , Proteômica , Vacinação , Vacinas Acelulares/genética , Vacinas Acelulares/imunologia , Coqueluche/microbiologiaRESUMO
Bordetella bronchiseptica is pervasive in swine populations and plays multiple roles in respiratory disease. Additionally, B. bronchiseptica is capable of establishing long-term or chronic infections in swine. Bacterial biofilms are increasingly recognized as important contributors to chronic bacterial infections. Recently the polysaccharide locus bpsABCD has been demonstrated to serve a critical role in the development of mature biofilms formed by the sequenced laboratory strain of B. bronchiseptica We hypothesized that swine isolates would also have the ability to form mature biofilms and the bpsABCD locus would serve a key role in this process. A mutant containing an in-frame deletion of the bpsABCD structural genes was constructed in a wild-type swine isolate and found to be negative for poly-N-acetylglucosamine (PNAG)-like material by immunoblot assay. Further, the bpsABCD locus was found to be required for the development and maintenance of the three-dimensional structures under continuous-flow conditions. To investigate the contribution of the bpsABCD locus to the pathogenesis of B. bronchiseptica in swine, the KM22Δbps mutant was compared to the wild-type swine isolate for the ability to colonize and cause disease in pigs. The bpsABCD locus was found to not be required for persistence in the upper respiratory tract of swine. Additionally, the bpsABCD locus did not affect the development of anti-Bordetella humoral immunity, did not contribute to disease severity, and did not mediate protection from complement-mediated killing. However, the bpsABCD locus was found to enhance survival in the lower respiratory tract of swine.
Assuntos
Biofilmes/crescimento & desenvolvimento , Infecções por Bordetella/microbiologia , Bordetella bronchiseptica/patogenicidade , Polissacarídeos Bacterianos/metabolismo , Traqueia/microbiologia , Animais , Proteínas de Bactérias/genética , Infecções por Bordetella/imunologia , Bordetella bronchiseptica/química , Bordetella bronchiseptica/genética , Bordetella bronchiseptica/imunologia , Brônquios/microbiologia , Regulação Bacteriana da Expressão Gênica , Mutação , Nariz/microbiologia , SuínosRESUMO
We calculated the effectiveness of pertussis vaccine in preventing parapertussis among Oregon children 2 months to 10 years of age using 2 methods. During 2011-2016, the 2 VE methods found 66% (95% CI, 59-75%) and 82% (95% CI, 69-90%) effectiveness against parapertussis. Pertussis vaccine may induce cross-immunity.
Assuntos
Infecções por Bordetella/microbiologia , Infecções por Bordetella/prevenção & controle , Bordetella parapertussis/imunologia , Proteção Cruzada/imunologia , Vacina contra Coqueluche/imunologia , Potência de Vacina , Anticorpos Antibacterianos/sangue , Infecções por Bordetella/epidemiologia , Infecções por Bordetella/imunologia , Bordetella parapertussis/genética , Bordetella pertussis/genética , Bordetella pertussis/imunologia , Criança , Pré-Escolar , Feminino , Humanos , Lactente , Masculino , Oregon/epidemiologia , Vacina contra Coqueluche/administração & dosagem , Reação em Cadeia da Polimerase , Vacinação/estatística & dados numéricos , Coqueluche/prevenção & controleRESUMO
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.
Assuntos
Anticorpos Antibacterianos/imunologia , Infecções por Bordetella/imunologia , Bordetella parapertussis/crescimento & desenvolvimento , Armadilhas Extracelulares/imunologia , Neutrófilos/imunologia , Infecções por Bordetella/microbiologia , Bordetella parapertussis/imunologia , Bordetella parapertussis/patogenicidade , Armadilhas Extracelulares/microbiologia , Humanos , Macrófagos/imunologia , Macrófagos/microbiologia , Microdomínios da Membrana , Neutrófilos/microbiologia , Fagocitose/imunologia , Fagossomos/imunologiaRESUMO
The baboon model of Bordetella pertussis infection is the newest and most clinically accurate model of the human disease to date. However, among the 15 experimentally infected baboons in this study, a subset of baboons did not exhibit the expected high bacterial colonization levels or increase in white blood cell count. Moreover, cultures of nasopharyngeal wash samples from several baboons suggested B. bronchiseptica coinfection. Analysis of serum antibodies recognizing filamentous hemagglutinin, pertussis toxin and B. pertussis lipo-oligosaccharide indicated that several baboons had likely been previously exposed to Bordetella species and that prior exposure correlated with partial protection from B. pertussis infection. Notably, all animals with a baseline Fha titer of 5 IU/ml or below exhibited symptoms typical of the model, suggesting this value can be used as inclusion criteria for animals prior to study enrollment. While B. pertussis infection is endemic to human populations and B. bronchiseptica is common in wild small mammals, this study illustrates that baboons can readily harbor both organisms. Awareness of Bordetella species that share antigens capable of generating protective immune responses and tracking of prior exposure to those species is required for successful use of the baboon model of pertussis.