RESUMO
Physical separation between the mammalian immune system and commensal bacteria is necessary to limit chronic inflammation. However, selective species of commensal bacteria can reside within intestinal lymphoid tissues of healthy mammals. Here, we demonstrate that lymphoid-tissue-resident commensal bacteria (LRC) colonized murine dendritic cells and modulated their cytokine production. In germ-free and antibiotic-treated mice, LRCs colonized intestinal lymphoid tissues and induced multiple members of the IL-10 cytokine family, including dendritic-cell-derived IL-10 and group 3 innate lymphoid cell (ILC3)-derived IL-22. Notably, IL-10 limited the development of pro-inflammatory Th17 cell responses, and IL-22 production enhanced LRC colonization in the steady state. Furthermore, LRC colonization protected mice from lethal intestinal damage in an IL-10-IL-10R-dependent manner. Collectively, our data reveal a unique host-commensal-bacteria dialog whereby selective subsets of commensal bacteria interact with dendritic cells to facilitate tissue-specific responses that are mutually beneficial for both the host and the microbe.
Assuntos
Infecções por Bordetella/imunologia , Bordetella/imunologia , Células Dendríticas/imunologia , Interleucina-10/metabolismo , Intestinos/imunologia , Tecido Linfoide/imunologia , Células Th17/imunologia , Animais , Células Cultivadas , Citocinas/metabolismo , Células Dendríticas/microbiologia , Interleucina-10/genética , Interleucinas/genética , Interleucinas/metabolismo , Intestinos/microbiologia , Tecido Linfoide/microbiologia , Camundongos , Camundongos da Linhagem 129 , Camundongos Endogâmicos C57BL , Camundongos Knockout , Microbiota , Receptores de Interleucina-10/genética , Receptores de Interleucina-10/metabolismo , Simbiose/genética , Células Th17/microbiologia , Interleucina 22RESUMO
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
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
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
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
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
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/imunologiaRESUMO
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
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
The adenylate cyclase toxin-hemolysin (CyaA) plays a key role in the virulence of Bordetella pertussis. CyaA penetrates complement receptor 3-expressing phagocytes and catalyzes uncontrolled conversion of cytosolic ATP to the key second messenger molecule cAMP. This paralyzes the capacity of neutrophils and macrophages to kill bacteria by complement-dependent oxidative burst and opsonophagocytic mechanisms. We show that cAMP signaling through the protein kinase A (PKA) pathway activates Src homology domain 2 containing protein tyrosine phosphatase (SHP) 1 and suppresses production of bactericidal NO in macrophage cells. Selective activation of PKA by the cell-permeable analog N(6)-benzoyladenosine-3',5'-cyclic monophosphate interfered with LPS-induced inducible NO synthase (iNOS) expression in RAW264.7 macrophages, whereas inhibition of PKA by H-89 largely restored the production of iNOS in CyaA-treated murine macrophages. CyaA/cAMP signaling induced SHP phosphatase-dependent dephosphorylation of the c-Fos subunit of the transcription factor AP-1 and thereby inhibited TLR4-triggered induction of iNOS gene expression. Selective small interfering RNA knockdown of SHP-1, but not of the SHP-2 phosphatase, rescued production of TLR-inducible NO in toxin-treated cells. Finally, inhibition of SHP phosphatase activity by NSC87877 abrogated B. pertussis survival inside murine macrophages. These results reveal that an as yet unknown cAMP-activated signaling pathway controls SHP-1 phosphatase activity and may regulate numerous receptor signaling pathways in leukocytes. Hijacking of SHP-1 by CyaA action then enables B. pertussis to evade NO-mediated killing in sentinel cells of innate immunity.
Assuntos
Toxina Adenilato Ciclase/imunologia , Infecções por Bordetella/imunologia , Macrófagos/imunologia , Proteína Tirosina Fosfatase não Receptora Tipo 6/imunologia , Animais , Infecções por Bordetella/enzimologia , Bordetella pertussis/imunologia , Linhagem Celular , AMP Cíclico , Ativação Enzimática/imunologia , Humanos , Macrófagos/microbiologia , Camundongos , Camundongos Endogâmicos C57BL , Óxido Nítrico/biossíntese , Proteína Tirosina Fosfatase não Receptora Tipo 6/metabolismo , Reação em Cadeia da Polimerase em Tempo Real , Transdução de Sinais/imunologiaRESUMO
Bordetella bronchiseptica can use catecholamines to obtain iron from transferrin and lactoferrin via uptake pathways involving the BfrA, BfrD, and BfrE outer membrane receptor proteins, and although Bordetella pertussis has the bfrD and bfrE genes, the role of these genes in iron uptake has not been demonstrated. In this study, the bfrD and bfrE genes of B. pertussis were shown to be functional in B. bronchiseptica, but neither B. bronchiseptica bfrD nor bfrE imparted catecholamine utilization to B. pertussis. Gene fusion analyses found that expression of B. bronchiseptica bfrA was increased during iron starvation, as is common for iron receptor genes, but that expression of the bfrD and bfrE genes of both species was decreased during iron limitation. As shown previously for B. pertussis, bfrD expression in B. bronchiseptica was also dependent on the BvgAS virulence regulatory system; however, in contrast to the case in B. pertussis, the known modulators nicotinic acid and sulfate, which silence Bvg-activated genes, did not silence expression of bfrD in B. bronchiseptica. Further studies using a B. bronchiseptica bvgAS mutant expressing the B. pertussis bvgAS genes revealed that the interspecies differences in bfrD modulation are partly due to BvgAS differences. Mouse respiratory infection experiments determined that catecholamine utilization contributes to the in vivo fitness of B. bronchiseptica and B. pertussis. Additional evidence of the in vivo importance of the B. pertussis receptors was obtained from serologic studies demonstrating pertussis patient serum reactivity with the B. pertussis BfrD and BfrE proteins.
Assuntos
Proteínas da Membrana Bacteriana Externa/imunologia , Infecções por Bordetella/imunologia , Bordetella bronchiseptica/patogenicidade , Bordetella pertussis/patogenicidade , Regulação Bacteriana da Expressão Gênica , Receptores de Catecolaminas/imunologia , Receptores de Superfície Celular/imunologia , Animais , Proteínas da Membrana Bacteriana Externa/genética , Proteínas de Bactérias/genética , Proteínas de Bactérias/imunologia , Infecções por Bordetella/microbiologia , Infecções por Bordetella/patologia , Bordetella bronchiseptica/genética , Bordetella bronchiseptica/imunologia , Bordetella bronchiseptica/metabolismo , Bordetella pertussis/genética , Bordetella pertussis/imunologia , Bordetella pertussis/metabolismo , Catecolaminas/imunologia , Catecolaminas/metabolismo , Humanos , Ferro/imunologia , Ferro/metabolismo , Camundongos , Camundongos Endogâmicos BALB C , Isoformas de Proteínas/genética , Isoformas de Proteínas/imunologia , Receptores de Catecolaminas/genética , Receptores de Superfície Celular/genética , Sideróforos/imunologia , Sideróforos/metabolismo , Especificidade da Espécie , Fatores de Transcrição/genética , Fatores de Transcrição/imunologia , VirulênciaRESUMO
Taishan Pinus massoniana pollen polysaccharide (TPPPS), propolis (PP) and aloe polysaccharide (AP), used as adjuvants, have been proven to possess immunity-enhancing functions. However, their collaborative immunomodulatory effects are largely unknown. To determine which combination can induce the best effects, the three adjuvants were separately or conjointly added into Bordetella avium inactivated vaccines to investigate their co-adjuvant effects on vaccinated chickens. We found that, among all six adjuvant-treated vaccine inoculated groups (TPPPS, PP, AP, TPPPS-PP, PP-AP and TPPPS-AP), the chickens inoculated with TPPPS, PP or TPPPS-PP adjuvant vaccines showed significantly higher levels of antibody titre, cytokine, lymphocyte transformation and peripheral blood T-lymphocyte count than those of non-adjuvant vaccine inoculated groups (P < 0.05), indicating the good immune-enhancing effects of TPPPS and PP. The TPPPS-PP group showed the highest levels of antibody titres and interleukin-2 (IL-2) at 14-28 days post the first inoculation (dpi), lymphocyte transformation rates (LTRs) at 14-35 dpi, CD4(+) T-lymphocyte counts at 14-42 dpi, and CD8(+) T-lymphocyte counts at 28 dpi. The results revealed that B. avium inactivated vaccine used conjointly with TPPPS and PP induced the strongest humoral and cellular immune responses. Thus, there was a synergistic effect between TPPPS and PP on enhancing immunity, which suggests that they can be used as a novel adjuvant formulation for the development of poultry vaccines.
Assuntos
Infecções por Bordetella/veterinária , Bordetella avium/imunologia , Galinhas/imunologia , Polissacarídeos/administração & dosagem , Doenças das Aves Domésticas/imunologia , Própole/administração & dosagem , Adjuvantes Imunológicos/administração & dosagem , Animais , Infecções por Bordetella/imunologia , Infecções por Bordetella/microbiologia , Infecções por Bordetella/prevenção & controle , Pinus/química , Pólen/química , Doenças das Aves Domésticas/microbiologia , Doenças das Aves Domésticas/prevenção & controle , Linfócitos T/imunologia , Vacinação/veterinária , Vacinas de Produtos InativadosRESUMO
BACKGROUND: Vaccine development has largely focused on the ability of vaccines to reduce disease in individual hosts, with less attention to assessing the vaccine's effects on transmission between hosts. Current acellular vaccines against Bordetella pertussis are effective in preventing severe disease but have little effect on less severe coughing illness that can mediate transmission. METHODS: Using mice that are natural host's of Bordetella bronchiseptica, we determined the effects of vaccination on shedding and transmission of this pathogen. RESULTS: Vaccination with heat-killed whole-cell B. bronchiseptica or B. pertussis inhibited shedding of B. bronchiseptica. Differences in neutrophil and B-cell recruitment distinguished sham-vaccine from whole-cell-----vaccine responses and correlated with shedding output. Both B and T cells were essential for vaccine-induced control of shedding. Adoptive transfer of antibodies was able to limit shedding, while depletion of CD4(+) T cells led to increased shedding in vaccinated mice. Finally, whole-cell vaccination was able to prevent transmission, but an acellular vaccine that effectively controls disease failed to control shedding and transmission. CONCLUSIONS: Our results highlight discrepancies between whole-cell and acellular vaccination that could contribute to the increased incidence of B. pertussis infection since the transition to the use of acellular vaccination.
Assuntos
Vacinas Bacterianas/imunologia , Infecções por Bordetella/prevenção & controle , Bordetella bronchiseptica/imunologia , Bordetella pertussis/imunologia , Vacinação/métodos , Animais , Linfócitos B/imunologia , Infecções por Bordetella/imunologia , Infecções por Bordetella/transmissão , Contagem de Linfócito CD4 , Camundongos , Camundongos Endogâmicos C3H , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Vacinas Acelulares/imunologiaRESUMO
Bordetella bronchiseptica is pervasive in swine populations and plays multiple roles in respiratory disease. Most studies addressing virulence factors of B. bronchiseptica utilize isolates derived from hosts other than pigs in conjunction with rodent infection models. Based on previous in vivo mouse studies, we hypothesized that the B. bronchiseptica type III secretion system (T3SS) would be required for maximal disease severity and persistence in the swine lower respiratory tract. To examine the contribution of the T3SS to the pathogenesis of B. bronchiseptica in swine, we compared the abilities of a virulent swine isolate and an isogenic T3SS mutant to colonize, cause disease, and be transmitted from host to host. We found that the T3SS is required for maximal persistence throughout the lower swine respiratory tract and contributed significantly to the development of nasal lesions and pneumonia. However, the T3SS mutant and the wild-type parent are equally capable of transmission among swine by both direct and indirect routes, demonstrating that transmission can occur even with attenuated disease. Our data further suggest that the T3SS skews the adaptive immune response in swine by hindering the development of serum anti-Bordetella antibody levels and inducing an interleukin-10 (IL-10) cell-mediated response, likely contributing to the persistence of B. bronchiseptica in the respiratory tract. Overall, our results demonstrate that the Bordetella T3SS is required for maximal persistence and disease severity in pigs, but not for transmission.
Assuntos
Sistemas de Secreção Bacterianos/imunologia , Infecções por Bordetella/imunologia , Bordetella bronchiseptica/imunologia , Fatores de Virulência de Bordetella/imunologia , Animais , Anticorpos Antibacterianos/imunologia , Proteínas de Bactérias/imunologia , Infecções por Bordetella/microbiologia , Proteínas de Transporte/imunologia , Interleucina-10/imunologia , Peptídeos/imunologia , Sistema Respiratório/imunologia , Sistema Respiratório/microbiologia , Suínos , Doenças dos Suínos/imunologia , Doenças dos Suínos/microbiologiaRESUMO
Bordetella bronchiseptica (Bb) whole cell bacterins have been replaced with acelluar vaccines. We evaluated the response to the acellular Bb vaccines in Bb-seropositive commingled laboratory beagles and client-owned dogs with various lifestyles and vaccination histories. A single parenteral dose of the acellular Bb vaccine resulted in consistent anamnestic IgG, and to a lesser, but notable extent, IgA, Bb-reactive antibody responses in the seropositive beagles. Associated with the increase in antibodies measured by enzyme-linked immunosorbent assay (ELISA) was an increase in the complement (C)-dependent IgG antibody mediated bactericidal effect on Bb in vitro. Antibody responses in client-owned dogs were more variable and were dependent upon the vaccination history and serological evidence of previous Bb exposure. Antibodies from vaccinated dogs recognized several Bb proteins, notably P68 (pertactin) and P220 (fimbrial hemagglutinin), the response to which has been shown to be disease-sparing in Bp infections. These antibody responses were similar to those in experimentally infected dogs and in dogs that had received a widely used whole cell bacterin.
Réponses des anticorps àBordetella bronchisepticachez des chiens vaccinés et infectés. Des bactérines de Bordetella bronchiseptica (Bb) ont été remplacées par des vaccins acellulaires. Nous avons évalué la réponse aux vaccins Bb acellulaires chez un groupe de Beagles de laboratoire séropositifs pour le Bb et des chiens de clients ayant divers styles de vie et antécédents de vaccination. Une seule dose parentérale du vaccin Bb acellulaire s'est traduite par une réponse IgG anamnestique uniforme, et à degré inférieur mais significatif, des réponses IgA et des anticorps réactifs à Bb chez les Beagles séropositifs. Une hausse des anticorps mesurés par ELISA a été accompagnée d'une augmentation de l'effet bactéricide atténué des anticorps dépendants IgG du complément (C) sur Bb in vitro. Les réponses des anticorps chez les chiens appartenant à des clients étaient plus variables et dépendaient des antécédents de vaccination et des preuves sérologiques d'une exposition antérieure à Bb. Les anticorps de chiens vaccinés reconnaissaient plusieurs protéines Bb, notamment P68 (pertactine) et P220 (hémagglutinine fimbriale), dont la réponse a été démontrée comme une protection contre la maladie lors d'une infection par Bb. Ces réponses des anticorps étaient semblables à celles des chiens infectés par expérimentation et à celles des chiens qui avaient reçu des bactérines à bacilles entiers généralement utilisés.(Traduit par Isabelle Vallières).
Assuntos
Anticorpos Antibacterianos/sangue , Infecções por Bordetella/veterinária , Bordetella bronchiseptica/imunologia , Doenças do Cão/imunologia , Animais , Vacinas Bacterianas/administração & dosagem , Vacinas Bacterianas/imunologia , Infecções por Bordetella/imunologia , Infecções por Bordetella/prevenção & controle , Cães , Ensaio de Imunoadsorção Enzimática/veterinária , Feminino , Imunoglobulina G/sangue , Injeções Subcutâneas/veterinária , Masculino , Vacinação/veterináriaRESUMO
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
The type III secretion system (T3SS) of pathogenic bordetellae employs a self-associating tip complex protein Bsp22. This protein is immunogenic during infections by Bordetella bronchiseptica and could be used as a protective antigen to immunize mice against B. bronchiseptica challenge. Since low-passage clinical isolates of the human pathogen Bordetella pertussis produce a highly homologous Bsp22 protein (97% homology), we examined its vaccine and diagnostic potential. No Bsp22-specific antibodies were, however, detected in serum samples from 36 patients with clinically and serologically confirmed whooping cough disease (pertussis syndrome). Moreover, although the induction of Bsp22 secretion by the laboratory-adapted 18323 strain in the course of mice lung infection was observed, the B. pertussis 18323-infected mice did not mount any detectable serum antibody response against Bsp22. Furthermore, immunization with recombinant Bsp22 protein yielded induction of high Bsp22-specific serum antibody titers but did not protect mice against an intranasal challenge with B. pertussis 18323. Unlike for B. bronchiseptica, hence, the Bsp22 protein is nonimmunogenic, and/or the serum antibody response to it is suppressed, during B. pertussis infections of humans and mice.
Assuntos
Antígenos de Bactérias/imunologia , Proteínas de Bactérias/imunologia , Infecções por Bordetella/imunologia , Bordetella pertussis/imunologia , Coqueluche/imunologia , Animais , Anticorpos Antibacterianos/sangue , Anticorpos Antibacterianos/imunologia , Formação de Anticorpos/imunologia , Ensaio de Imunoadsorção Enzimática , Humanos , Camundongos , Camundongos Endogâmicos BALB CRESUMO
The exacerbated induction of innate immune responses in airways can abrogate diverse lung infections by a phenomenon known as stimulated innate resistance (StIR). We recently demonstrated that the enhancement of innate response activation can efficiently impair Bordetella pertussis colonization in a Toll-like receptor 4 (TLR4)-dependent manner. The aim of this work was to further characterize the effect of lipopolysaccharide (LPS) on StIR and to identify the mechanisms that mediate this process. Our results showed that bacterial infection was completely abrogated in treated mice when the LPS of B. pertussis (1 µg) was added before (48 h or 24 h), after (24 h), or simultaneously with the B. pertussis challenge (10(7) CFU). Moreover, we detected that LPS completely cleared bacterial infection as soon as 2 h posttreatment. This timing suggests that the observed StIR phenomenon should be mediated by fast-acting antimicrobial mechanisms. Although neutrophil recruitment was already evident at this time point, depletion assays using an anti-GR1 antibody showed that B. pertussis clearance was achieved even in the absence of neutrophils. To evaluate the possible role of free radicals in StIR, we performed animal assays using the antioxidant N-acetyl cysteine (NAC), which is known to inactivate oxidant species. NAC administration blocked the B. pertussis clearance induced by LPS. Nitrite concentrations were also increased in the LPS-treated mice; however, the inhibition of nitric oxide synthetases did not suppress the LPS-induced bacterial clearance. Taken together, our results show that reactive oxygen species (ROS) play an essential role in the TLR4-dependent innate clearance of B. pertussis.
Assuntos
Infecções por Bordetella/imunologia , Bordetella pertussis/patogenicidade , Imunidade Inata , Espécies Reativas de Oxigênio/imunologia , Acetilcisteína/administração & dosagem , Acetilcisteína/farmacologia , Animais , Carga Bacteriana , Infecções por Bordetella/microbiologia , Bordetella pertussis/efeitos dos fármacos , Bordetella pertussis/imunologia , Guanidinas/farmacologia , Lipopolissacarídeos/imunologia , Lipopolissacarídeos/farmacologia , Pulmão/imunologia , Pulmão/microbiologia , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C3H , Óxido Nítrico Sintase/antagonistas & inibidores , Óxido Nítrico Sintase/metabolismo , Nitritos/metabolismo , Fatores de Tempo , Receptor 4 Toll-Like/imunologiaRESUMO
BACKGROUND: Horizontal gene transfer (HGT) allows for rapid spread of genetic material between species, increasing genetic and phenotypic diversity. Although HGT contributes to adaptation and is widespread in many bacteria, others show little HGT. This study builds on previous work to analyze the evolutionary mechanisms contributing to variation within the locus encoding a prominent antigen of the classical bordetellae. RESULTS: We observed amongst classical bordetellae discrete regions of the lipopolysaccharide O-antigen locus with higher sequence diversity than the genome average. Regions of this locus had less than 50% sequence similarity, low dN/dS ratios and lower GC content compared to the genome average. Additionally, phylogenetic tree topologies based on genome-wide SNPs were incongruent with those based on genes within these variable regions, suggesting portions of the O-antigen locus may have been horizontally transferred. Furthermore, several predicted recombination breakpoints correspond with the ends of these variable regions. To examine the evolutionary forces that might have selected for this rare example of HGT in bordetellae, we compared in vitro and in vivo phenotypes associated with different O-antigen types. Antibodies against O1- and O2-serotypes were poorly cross-reactive, and did not efficiently kill or mediate clearance of alternative O-type bacteria, while a distinct and poorly immunogenic O-antigen offered no protection against colonization. CONCLUSIONS: This study suggests that O-antigen variation was introduced to the classical bordetellae via HGT through recombination. Additionally, genetic variation may be maintained within the O-antigen locus because it can provide escape from immunity to different O-antigen types, potentially allowing for the circulation of different Bordetella strains within the same host population.