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2.
Vet Microbiol ; 235: 285-288, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31383314

RESUMO

Domestic pigs and wild suids are susceptible to Mycobacterium bovis (M. bovis) infection and may even serve as reservoir hosts in some situations. Therefore, detection of infected animals is important for understanding their role in the epidemiology of the disease as well as for management and control of bovine tuberculosis. Infected suids develop strong humoral responses, making serological screening a feasible approach to disease surveillance. However, to optimize sensitivity of the antibody assays, it is necessary to identify and incorporate immunodominant antigens recognized by the target species. The objective of this study was to characterize the antigen recognition by three suid species in a commercially available serological test, DPP VetTB Assay. Serum samples from naturally M. bovis-infected domestic pigs, wild boar and common warthogs were tested. MPB83 protein appeared to be the immunodominant antigen recognized by antibodies in all three species. Overall test sensitivity was increased in wild suids when seroreactivity to CFP10/ESAT-6 antigen was included. Infected animals with visible lesions showed more robust antibody responses than those without gross lesions. The high sensitivity and specificity of the DPP VetTB Assay demonstrated in the present study supports the utility of antibody tests employing these antigens in serological screening of the suid species for M. bovis infection.


Assuntos
Antígenos de Bactérias/imunologia , Proteínas de Bactérias/imunologia , Proteínas de Membrana/imunologia , Mycobacterium bovis/imunologia , Animais , Animais Domésticos/imunologia , Animais Domésticos/microbiologia , Anticorpos Antibacterianos/sangue , Sensibilidade e Especificidade , Testes Sorológicos , Sus scrofa/imunologia , Sus scrofa/microbiologia , Suínos
3.
Int J Infect Dis ; 87: 32-38, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31442625

RESUMO

BACKGROUND: Mycobacterium bovis BCG is a live, attenuated tuberculosis vaccine. While the vaccine protects infants from tuberculosis, complications including disseminated infections have been reported following vaccination. Genetically diverse BCG sub-strains now exist following continuous passaging of the original Pasteur strain for vaccine manufacture. This genetic diversity reportedly influences the severity of disseminated BCG infections and the efficacy of BCG immunization. METHODS: M. bovis BCG was isolated from infants suspected of being infected with tuberculosis. The whole genome of the clinical isolates and BCG Moscow were sequenced using Illumina Miseq and the sequences were analysed using CLC Genomics Workbench 7.0, PhyResSE v1.0, and Parsnp. RESULTS AND CONCLUSIONS: Genetic variations between the clinical strains and the reference BCG Copenhagen were identified. The clinical strains shared only one mutation in a secretion protein. Mutations were identified in various antibiotic resistance genes in the BCG isolates, which suggests their potential as multidrug-resistant (MDR) phenotypes. Phylogenetic analysis showed that the two isolates were distantly related, and the M1_S48 clinical isolate was closely related to M. bovis BCG Moscow. The phylogenomics results imply that two different BCG strains may be circulating in South Africa. However, it is difficult to associate the BCG vaccine strain administered and the BCG strain supplied with specific adverse events, as BCGiosis is under-reported. This study presents background genomic information for future surveillance and tracking of the distribution of BCGiosis-associated mycobacteria. It is also the first to report on the genomes of clinical BCG strains in Africa.


Assuntos
Vacina BCG/efeitos adversos , Mycobacterium bovis/classificação , Filogenia , Tuberculose/virologia , Vacina BCG/genética , Vacina BCG/imunologia , Sequência de Bases , Feminino , Humanos , Lactente , Masculino , Mutação , Mycobacterium bovis/genética , Mycobacterium bovis/imunologia , Mycobacterium bovis/isolamento & purificação , África do Sul/epidemiologia , Tuberculose/epidemiologia , Tuberculose/etiologia , Tuberculose/prevenção & controle , Vacinas Atenuadas/efeitos adversos , Vacinas Atenuadas/genética , Vacinas Atenuadas/imunologia
4.
Emerg Microbes Infect ; 8(1): 1168-1177, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31379262

RESUMO

Mannose-capped lipoarabinomannan (ManLAM) is a high molecular mass amphipathic lipoglycan identified in pathogenic Mycobacterium tuberculosis (M. tb) and M. bovis Bacillus Calmette-Guérin (BCG). ManLAM, serves as both an immunogen and a modulator of the host immune system, and its critical role in mycobacterial survival during infection has been well-characterized. ManLAM can be recognized by various types of receptors on both innate and adaptive immune cells, including macrophages, dendritic cells (DCs), neutrophils, natural killer T (NKT) cells, T cells and B cells. MamLAM has been shown to affect phagocytosis, cytokine production, antigen presentation, T cell activation and polarization, as well as antibody production. Exploring the mechanisms underlying the roles of ManLAM during mycobacterial infection will aid in improving tuberculosis (TB) prevention, diagnosis and treatment interventions. In this review, we highlight the interaction between ManLAM and receptors, intracellular signalling pathways triggered by ManLAM and its roles in both innate and adaptive immune responses.


Assuntos
Imunidade Adaptativa/efeitos dos fármacos , Imunidade Inata/efeitos dos fármacos , Fatores Imunológicos/análise , Lipopolissacarídeos/análise , Manose/análise , Mycobacterium bovis/química , Mycobacterium tuberculosis/química , Animais , Humanos , Mycobacterium bovis/imunologia , Mycobacterium tuberculosis/imunologia , Receptores Imunológicos/agonistas , Transdução de Sinais
5.
J Dairy Sci ; 102(9): 8405-8409, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31301842

RESUMO

Different mycobacterial species are encountered in bovine medicine. The fastidiously growing mycobacteria (Mycobacterium bovis as the cause of bovine tuberculosis, and Mycobacterium avium ssp. paratuberculosis, MAP, as the cause of paratuberculosis) are well known and targeted in eradication/control or monitoring programs in different countries, whereas the rapidly growing species is only rarely identified from bovine disease. The latter have occasionally been reported as the cause of bovine clinical mastitis, but recent reports are scarce. In this study, Mycolicibacterium smegmatis (basonym Mycobacterium smegmatis) was identified as cause of granulomatous, relapsing clinical mastitis in 2 cows from one Belgian dairy herd. Milk, blood, and fecal samples were collected, as well as tissue samples after the cows were culled. Serological analysis conducted on milk and serum samples resulted in positive reactions for MAP, but negative for Mycobacterium bovis. Production of IFN-γ showed sensitization with mycobacteria or similar organisms, other than M. bovis, in one cow. Detection of MAP by bacteriological culture and IS900-based quantitative PCR on milk and feces remained negative. In conclusion, this paper describes M. smegmatis as a cause of bovine clinical mastitis in Belgium and suggests cross-reactivity of the intramammary M. smegmatis infection with routinely used serological tests for MAP.


Assuntos
Doenças dos Bovinos/microbiologia , Mastite Bovina/microbiologia , Mycobacterium smegmatis , Paratuberculose/diagnóstico , Animais , Bélgica , Bovinos , Doenças dos Bovinos/diagnóstico , Reações Cruzadas , Fezes/microbiologia , Feminino , Leite/microbiologia , Mycobacterium avium subsp. paratuberculosis/imunologia , Mycobacterium bovis/imunologia , Mycobacterium smegmatis/imunologia , Paratuberculose/microbiologia , Reação em Cadeia da Polimerase em Tempo Real/veterinária , Tuberculose Bovina
6.
BMC Genomics ; 20(1): 561, 2019 Jul 08.
Artigo em Inglês | MEDLINE | ID: mdl-31286858

RESUMO

BACKGROUND: Mycobacterium bovis bacillus Calmette-Guérin (M. bovis BCG) is the only vaccine available against tuberculosis (TB). In an effort to standardize the vaccine production, three substrains, i.e. BCG Danish 1331, Tokyo 172-1 and Russia BCG-1 were established as the WHO reference strains. Both for BCG Tokyo 172-1 as Russia BCG-1, reference genomes exist, not for BCG Danish. In this study, we set out to determine the completely assembled genome sequence for BCG Danish and to establish a workflow for genome characterization of engineering-derived vaccine candidate strains. RESULTS: By combining second (Illumina) and third (PacBio) generation sequencing in an integrated genome analysis workflow for BCG, we could construct the completely assembled genome sequence of BCG Danish 1331 (07/270) (and an engineered derivative that is studied as an improved vaccine candidate, a SapM KO), including the resolution of the analytically challenging long duplication regions. We report the presence of a DU1-like duplication in BCG Danish 1331, while this tandem duplication was previously thought to be exclusively restricted to BCG Pasteur. Furthermore, comparative genome analyses of publicly available data for BCG substrains showed the absence of a DU1 in certain BCG Pasteur substrains and the presence of a DU1-like duplication in some BCG China substrains. By integrating publicly available data, we provide an update to the genome features of the commonly used BCG strains. CONCLUSIONS: We demonstrate how this analysis workflow enables the resolution of genome duplications and of the genome of engineered derivatives of the BCG Danish vaccine strain. The BCG Danish WHO reference genome will serve as a reference for future engineered strains and the established workflow can be used to enhance BCG vaccine standardization.


Assuntos
Vacina BCG/imunologia , Genômica/normas , Mycobacterium bovis/genética , Mycobacterium bovis/imunologia , Organização Mundial da Saúde , Genoma Bacteriano/genética , Padrões de Referência
7.
BMC Infect Dis ; 19(1): 568, 2019 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-31262260

RESUMO

BACKGROUND: With the aim of preparing a more effective, safe and economical vaccine for tuberculosis, inhalable live mycobacterium formulations were evaluated. METHODS: Alginate particles in the size range of 2-4 µm were prepared by encapsulating live Bacille Calmette-Guérin (BCG) and "Mycobacterium indicus pranii" (MIP). These particles were characterized for their size, stability and release profile. Mice were immunized with liquid aerosol or dry powder aerosol (DPA) alginate encapsulated mycobacterium particles and their in-vitro recall response and infection with mycobacterium H37Rv were investigated. RESULTS: It was found that the DPA of alginate encapsulated mycobacterium particles invoked superior immune response and provided higher protection in mice than the liquid aerosol. The BCG encapsulated in alginate particles (BEAP) and MIP encapsulated in alginate particles (MEAP) were engulfed by bone marrow dendritic cells (BMDCs) and co-localized with lysosome. The MEAP/BEAP activated BMDCs exhibited higher chemotaxis movement and had enhanced ability of antigen presentation to T cells. The in-vitro recall response of BEAP/MEAP immunized mice when compared in terms of proliferation index and Interferon gamma (IFN-gamma) released by splenocytes and mediastinal lymph node cells was found to be higher than mice immunized by liquid aerosol of BCG/MIP. Finally, different groups of immunized mice were infected with M. tb H37Rv and after 16 weeks the Colony forming units (CFUs) in lung and spleen estimated. The bacilli burden in the BEAP/MEAP immunized mice was significantly less than the respective liquid aerosol immunized mice and the histopathology of BEAP/MEAP immunized mice lungs showed very little damage. CONCLUSIONS: These inhale-able vaccines formulation of alginate coated live mycobacterium are more immunogenic as compared to the aerosol of bacilli and they provide better protection in mice when infected with H37Rv.


Assuntos
Aerossóis/administração & dosagem , Pulmão/imunologia , Vacinas contra a Tuberculose/farmacologia , Tuberculose/prevenção & controle , Alginatos/química , Animais , Vacina BCG/imunologia , Sistemas de Liberação de Medicamentos/métodos , Interferon gama/imunologia , Pulmão/efeitos dos fármacos , Pulmão/microbiologia , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Complexo Mycobacterium avium/química , Complexo Mycobacterium avium/imunologia , Mycobacterium bovis/química , Mycobacterium bovis/imunologia , Mycobacterium tuberculosis/imunologia , Mycobacterium tuberculosis/patogenicidade , Baço/microbiologia , Linfócitos T/imunologia , Linfócitos T/microbiologia , Tuberculose/imunologia , Vacinas contra a Tuberculose/administração & dosagem , Vacinas contra a Tuberculose/imunologia , Vacinação/métodos
8.
Immunohorizons ; 3(5): 161-171, 2019 05 16.
Artigo em Inglês | MEDLINE | ID: mdl-31356170

RESUMO

During Ag priming, naive CD4+ T cells differentiate into subsets with distinct patterns of cytokine expression that dictate to a major extent their functional roles in immune responses. We identified a subset of CD4+ T cells defined by secretion of IL-3 that was induced by Ag stimulation under conditions different from those associated with previously defined functional subsets. Using mouse models of bacterial and viral infections, we showed that IL-3-secreting CD4+ T cells were generated by infection at the skin and mucosa but not by infections introduced directly into the blood. Most IL-3-producing T cells coexpressed GM-CSF and other cytokines that define multifunctionality. Generation of IL-3-secreting T cells in vitro was dependent on IL-1 family cytokines and was inhibited by cytokines that induce canonical Th1 or Th2 cells. Our results identify IL-3-secreting CD4+ T cells as a potential functional subset that arises during priming of naive T cells in specific tissue locations.


Assuntos
Interleucina-3/biossíntese , Membrana Mucosa/microbiologia , Pele/microbiologia , Células Th1/imunologia , Células Th2/imunologia , Animais , Modelos Animais de Doenças , Feminino , Fator Estimulador de Colônias de Granulócitos e Macrófagos/metabolismo , Herpes Genital/virologia , Herpesvirus Humano 2/imunologia , Listeria monocytogenes/imunologia , Listeriose/microbiologia , Ativação Linfocitária/imunologia , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Membrana Mucosa/imunologia , Membrana Mucosa/virologia , Mycobacterium bovis/imunologia , Pele/imunologia , Pele/virologia , Tuberculose/microbiologia
9.
Microb Pathog ; 134: 103574, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31170450

RESUMO

The present study was aimed to assess the prevalence and efficiency of techniques for the diagnosis of bovine tuberculosis (bTB) including enzyme-linked immunosorbent assay (ELISA), Gamma interferon assay (IFN-γ) and polymerase chain reaction (PCR) in comparison to skin tuberculin test and culture technique. A total of 2600 cross-breed dairy cattle in Menoufia and Daqahlia governorates were tested by the single intradermal tuberculin test where the disease prevalence was 1.8%. Serum and whole blood samples were collected from positive tuberculin reactors for ELISA and IFN-γ assay, respectively. After slaughtering of positive tuberculin reactors, the post-mortem examination was carried out and tissue samples were collected for the bacteriological examination and PCR. The percentage of visible lesions of tuberculin reactors was 78.7%, while non-visible lesions were 21.27%. Culture technique revealed that the percentage of bTB was 63.8%. The ELISA and IFN-γ assay using short-term culture filtrate (ST-CF) prepared antigen revealed higher sensitivity (72.3% and 82.9%) than the bovine purified protein derivative (PPD-B) antigen. Although prepared ST-CF antigen has great efficiency and eligibility for the diagnosis of bTB, PCR appeared to have a higher sensitivity (85.1%) than other diagnostic methods when dealing with post-mortem samples. Gamma interferon assay using ST-CF antigen is recommended for antemortem diagnosis of bTB in cattle.


Assuntos
Técnicas Bacteriológicas/métodos , Interferon gama/sangue , Mycobacterium bovis/isolamento & purificação , Tuberculose Bovina/diagnóstico , Animais , Bovinos , Técnicas de Cultura/métodos , Ensaio de Imunoadsorção Enzimática/métodos , Mycobacterium bovis/imunologia , Reação em Cadeia da Polimerase/métodos , Prevalência , Sensibilidade e Especificidade , Tuberculina , Teste Tuberculínico/métodos , Tuberculose Bovina/epidemiologia , Tuberculose Bovina/imunologia , Tuberculose Bovina/microbiologia
10.
PLoS Pathog ; 15(6): e1007866, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-31188899

RESUMO

The gastric lamina propria of mice that have been experimentally infected with the pathobiont Helicobacter pylori hosts a dense network of myeloid cells that includes BATF3-dependent CD103+ dendritic cells (DCs). We show here that CD103+ DCs are strictly required for gastric Th1 responses to H. pylori and for H. pylori infection control. A similar dependence of type 1 immunity on CD103+ DCs is observed in a Mycobacterium bovis BCG infection model, and in a syngeneic colon cancer model. Strikingly, we find that not only the expansion and/or recruitment of Th1 cells, but also of peripherally induced, neuropilin-negative regulatory T-cells to sites of infection requires BATF3-dependent DCs. A shared feature of the examined models is the strongly reduced production of the chemokines and CXCR3 ligands CXCL9, 10 and 11 in BATF3-deficient mice. The results implicate BATF3-dependent DCs in the recruitment of CXCR3+ effector and regulatory T-cells to target tissues and in their local expansion.


Assuntos
Fatores de Transcrição de Zíper de Leucina Básica/imunologia , Células Dendríticas/imunologia , Infecções por Helicobacter/imunologia , Helicobacter pylori/imunologia , Mycobacterium bovis/imunologia , Proteínas Repressoras/imunologia , Linfócitos T Reguladores/imunologia , Tuberculose/imunologia , Animais , Fatores de Transcrição de Zíper de Leucina Básica/genética , Linhagem Celular Tumoral , Quimiocinas CXC/genética , Quimiocinas CXC/imunologia , Células Dendríticas/microbiologia , Células Dendríticas/patologia , Infecções por Helicobacter/genética , Infecções por Helicobacter/patologia , Camundongos , Camundongos Knockout , Receptores CXCR3/genética , Receptores CXCR3/imunologia , Proteínas Repressoras/genética , Linfócitos T Reguladores/microbiologia , Linfócitos T Reguladores/patologia , Tuberculose/genética , Tuberculose/patologia
12.
Scand J Immunol ; 90(4): e12772, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31055842

RESUMO

Bacillus Calmette-Guérin (BCG) remains the only licensed vaccine against human tuberculosis (TB). BCG is a live-attenuated strain of Mycobacterium bovis, with limitations in efficacy against respiratory TB, the most common form of the disease responsible for transmission. However, continues to be used in the immunization programmes of different countries in the absence of another alternative. In order to improve BCG efficacy against pulmonary TB, in the current clinical TB vaccine pipeline, there are live-attenuated TB vaccines to replace BCG. This review discusses the current status of the development of live vaccine candidates designed to replace BCG from the rational strategies and immunological challenges to its clinical trial and identify key areas in the next years considered essential to confer improved safety and efficacy over BCG.


Assuntos
Mycobacterium bovis/imunologia , Mycobacterium tuberculosis/fisiologia , Vacinas contra a Tuberculose/imunologia , Tuberculose Pulmonar/imunologia , Vacinas Atenuadas/imunologia , Animais , Humanos , Vacinação
13.
Mol Immunol ; 112: 115-122, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-31082645

RESUMO

Mycobacterium tuberculosis (M. tuberculosis) persistent infection might cause the dysfunction of hematopoiesis. To investigate whether M. tuberculosis persistent antigen stimulation impairs the proliferation and differentiation of hematopoietic stem and progenitor cells characterized as lineage- c-Kit+ (LK cells), C57BL/6 mice were primed with Mycobacterium bovis Bacillus Calmette-Guérin (BCG) and boosted with a cocktail of M. tuberculosis antigens ESAT6, CFP10 and Mtb10.4-HspX (MH) along with adjuvant N, N'-dimethyl-N, N'-dioctadecylammonium bromide (DDA) plus polyinosinic-polycytidylic acid (Poly I:C) weekly for 12 or 22 weeks. The cytokine production by splenic T cells, proliferation of LK cells and transcriptional events during differentiation of bone marrow (BM) c-Kit+ cells were investigated. Meanwhile, the mice were treated with interleukin 2 (IL-2) and the therapeutic effects were analyzed. We found that antigen specific interferon-γ (IFN-γ) production by splenic CD4+ T cells increased following antigen stimulation for 12 weeks, but it declined after continuous stimulation for 22 weeks. The long-term exposure of mice to M. tuberculosis antigen compromised the proliferation of LK cells. Moreover, the expression of transcription factors in the c-Kit+ cells was adjusted, with up-regulation of IRF8 and Batf2 involved in myeloid differentiation and down-regulation of NOTCH1 and GATA2 participated in T-cell lineage commitment. The concentrations of IFN-γ in BM of the persistent antigen group were higher than that in sham control at the 12th week, while the concentrations of IL-2 in BM of the persistent antigen group were lower compared with the transient antigen stimulation control. Following IL-2 treatment, the concentrations of IL-2 in BM increased while IFN-γ got declined. IL-2 treatment could restore the expression levels of those transcription factors and the proliferating activity of LK cells impaired by persistent antigen stimulation. Our results indicate that M. tuberculosis antigen persistent stimulation decreases the proliferating activity of LK cells, promotes myelopoietic differentiation, and represses lymphopoietic differentiation as a consequence of elevated IFN-γ production. IL-2 supplementation contributes to maintaining the homeostasis of hemopoiesis.


Assuntos
Antígenos de Bactérias/imunologia , Medula Óssea/imunologia , Proliferação de Células/fisiologia , Mycobacterium tuberculosis/imunologia , Transcrição Genética/imunologia , Adjuvantes Imunológicos/farmacologia , Animais , Anticorpos Antibacterianos/imunologia , Proteínas de Bactérias/imunologia , Medula Óssea/microbiologia , Linfócitos T CD4-Positivos/imunologia , Diferenciação Celular/imunologia , Feminino , Transplante de Células-Tronco Hematopoéticas/métodos , Interferon gama/imunologia , Interleucina-2/imunologia , Camundongos , Camundongos Endogâmicos C57BL , Mycobacterium bovis/imunologia , Fatores de Transcrição/imunologia
14.
Res Vet Sci ; 125: 14-23, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31108426

RESUMO

This study aimed to evaluate the performance of real-time PCR (qPCR), ELISA IDEXX™, and bacterial isolation as post-mortem diagnostic tests in animals with lesions compatible with bovine tuberculosis detected by Brazilian Federal Inspection Service as part of the bovine tuberculosis active surveillance. Bayesian latent class models were used to estimate diagnostic tests' sensitivity, specificity, correlations, predictive values and frequency of infected animals. Samples of tuberculosis-suggestive lesions collected by FIS sanitary inspection routine in slaughterhouses from 11 Brazilian states were analyzed. Isolation was the most sensitive technique, 94.54% (95% Credible Interval (CrI) 90.09%-97.65%), qPCR was 64.69% (95% CrI 54.41%-74.15%) sensitive and ELISA IDEXX™ 26.74% (95% CrI 22.82%-30.97%). Tests' specificities were 98.19% (95% CrI 95.75%-99.45%), 93.49% (95% CrI 79.28%-99.66%), 95.53% (95% CrI 91.71%-98.02%) respectively. Despite its low sensitivity, ELISA IDEXX™ was able to identify positive samples that were not detected by the other techniques. These samples had high probability to be true positives given ELISA's positive predictive value. The correlations between qPCR and isolation were neither biologically nor statistically significant. The low sensitivity of the qPCR is a limiting factor to its use as a post-mortem diagnosis in bovine tuberculosis suggestive lesions. Its use could be recommended in situations of high prevalence, or in parallel association with other tests, such as ELISA IDEXX™. ELISA IDDEX™ should not be used as a unique test, or in substitution of the other tests, for the post-mortem diagnosis of bovine tuberculosis due to its sensitivity.


Assuntos
Mycobacterium bovis/isolamento & purificação , Tuberculose Bovina/diagnóstico , Matadouros , Animais , Autopsia , Teorema de Bayes , Brasil , Bovinos , Estudos Transversais , Testes Diagnósticos de Rotina/normas , Testes Diagnósticos de Rotina/veterinária , Ensaio de Imunoadsorção Enzimática , Análise de Classes Latentes , Mycobacterium bovis/genética , Mycobacterium bovis/imunologia , Reação em Cadeia da Polimerase em Tempo Real/veterinária , Sensibilidade e Especificidade
15.
Tuberculosis (Edinb) ; 116S: S42-S58, 2019 05.
Artigo em Inglês | MEDLINE | ID: mdl-31126718

RESUMO

Vitamin D3 is known to be a key component in the defense against Mycobacterium tuberculosis (Mtb) infection through the regulation of cytokine and effector molecules. Conversely, alcohol exposure has been recognized as an immune dysregulator. Macrophages were extracted from D3 deficient and sufficient diet mice and supplemented with D3 or exposed to ethanol during ex vivo infection using M. bovis BCG, as a surrogate for Mtb. Results of our study indicate that while exogenous supplementation or alcohol exposure did alter immune response, in vivo diet was the greatest determinant of cytokine and effector molecule production. Alcohol exposure was found to profoundly dysregulate primary murine macrophages, with ethanol-exposed cells generally characterized as hyper- or hyporesponsive. Exogenous D3 supplementation had a normative effect for diet deficient host, however supplementation was not sufficient to compensate for the effects of diet deficiency. Vitamin D3 sufficient diet resulted in reduced cell cytotoxicity for the majority of time points. Results provide insight into the ramifications of both the individual and combined health risks of D3 deficiency or alcohol exposure. Given the clinical relevance of D3 deficiency and alcohol use comorbidities, outcomes of this study have implications in therapeutic approaches for the treatment of tuberculosis disease.


Assuntos
Colecalciferol/farmacologia , Suplementos Nutricionais , Etanol/toxicidade , Macrófagos/efeitos dos fármacos , Mycobacterium bovis/patogenicidade , Tuberculose/microbiologia , Deficiência de Vitamina D/tratamento farmacológico , Animais , Carga Bacteriana , Células Cultivadas , Citocinas/metabolismo , Modelos Animais de Doenças , Feminino , Interações Hospedeiro-Patógeno , Macrófagos/imunologia , Macrófagos/metabolismo , Macrófagos/microbiologia , Camundongos Endogâmicos C57BL , Mycobacterium bovis/imunologia , Mycobacterium bovis/metabolismo , Tuberculose/imunologia , Tuberculose/metabolismo , Deficiência de Vitamina D/imunologia , Deficiência de Vitamina D/metabolismo , Deficiência de Vitamina D/microbiologia
16.
PLoS One ; 14(4): e0214859, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31002668

RESUMO

In developing an oral bait BCG vaccine against tuberculosis in badgers we wanted to understand the conditions of the gastrointestinal tract and their impact on vaccine viability. Conditions mimicking stomach and small-intestine caused substantial reduction in BCG viability. We performed in vivo experiments using a telemetric pH monitoring system and used the data to parameterise a dynamic in vitro system (TIM-1) of the stomach and small intestine. Some BCG died in the stomach compartment and through the duodenum and jejunum compartments. BCG survival in the stomach was greatest when bait was absent but by the time BCG reached the jejunum, BCG viability was not significantly affected by the presence of bait. Our data suggest that from a starting quantity of 2.85 ± 0.45 x 108 colony-forming units of BCG around 2 log10 may be killed before delivery to the intestinal lymphoid tissue. There are economic arguments for reducing the dose of BCG to vaccinate badgers orally. Our findings imply this could be achieved if we can protect BCG from the harsh environment of the stomach and duodenum. TIM-1 is a valuable, non-animal model with which to evaluate and optimise formulations to maximise BCG survival in the gastrointestinal tract.


Assuntos
Vacina BCG/administração & dosagem , Vacina BCG/imunologia , Mustelidae/imunologia , Mustelidae/microbiologia , Mycobacterium bovis/imunologia , Vacinação/veterinária , Administração Oral , Animais , Carga Bacteriana , Reservatórios de Doenças/microbiologia , Concentração de Íons de Hidrogênio , Técnicas In Vitro , Viabilidade Microbiana/imunologia , Modelos Biológicos , Tuberculose/imunologia , Tuberculose/prevenção & controle , Tuberculose/veterinária , Trato Gastrointestinal Superior/imunologia , Trato Gastrointestinal Superior/metabolismo , Trato Gastrointestinal Superior/microbiologia , Vacinação/métodos
17.
Tuberculosis (Edinb) ; 115: 113-120, 2019 03.
Artigo em Inglês | MEDLINE | ID: mdl-30948165

RESUMO

Diabetes is one of the major co-morbidities contributing to the high global burden of tuberculosis (TB). The increased susceptibility of individuals with type 2 diabetes (T2D) to TB is multifactorial and may influence the efficacy of vaccines. This study was undertaken to determine the early immune responses that occur following infection with Mycobacterium bovis Bacille Calmette-Guérin (BCG) in a diet-induced murine model of T2D. The phagocytic capabilities of alveolar (AM) and resident peritoneal macrophages (RPM) were assessed using ex vivo assays. Compared to macrophages from non-diabetic mice, macrophages from diabetic animals showed decreased BCG uptake and killing and inflammatory cytokine production (TNF-α, MCP-1, IL-6, IL-1ß). In vivo susceptibility to BCG was determined following intravenous infection and diabetic mice showed a trend towards increased mortality, higher bacterial burden in the lung, liver and spleen and increased inflammatory lesions compared to controls. Differences between tissue cytokines were observed as early as one day post-infection and by days 14 and 35, lung and liver TNF-α and IFN-γ levels were decreased in diabetic mice compared to controls. These results suggest that early dysregulated immune responses may influence the susceptibility of T2D mice to BCG infection.


Assuntos
Citocinas/metabolismo , Diabetes Mellitus Tipo 2/imunologia , Mycobacterium bovis/imunologia , Tuberculose/imunologia , Animais , Diabetes Mellitus Experimental/imunologia , Diabetes Mellitus Experimental/patologia , Diabetes Mellitus Tipo 2/patologia , Modelos Animais de Doenças , Suscetibilidade a Doenças , Imunidade Celular/imunologia , Fígado/química , Pulmão/química , Macrófagos/imunologia , Macrófagos/microbiologia , Masculino , Camundongos Endogâmicos C57BL , Fagocitose/imunologia , Tuberculose/patologia
19.
Artigo em Inglês | MEDLINE | ID: mdl-30881925

RESUMO

Vaccines are an environmentally friendly alternative to acaracides for the control of tick infestations, to reduce the risk for tick-borne diseases affecting human and animal health worldwide, and to improve animal welfare and production. Subolesin (SUB, also known as 4D8) is the functional homolog of Akirin2 involved in the regulation of development and innate immune response, and a proven protective antigen for the control of ectoparasite infestations and pathogen infection. Oral vaccination combining protein antigens with immunostimulants has proven efficacy with increased host welfare and safety, but has not been used for the control of tick infestations. Here we describe the efficacy of oral vaccination with a formulation combining Rhipicephalus microplus SUB and heat inactivated Mycobacterium bovis (IV) on cattle tick infestations and fertility. The levels of IgG antibody titers against SUB and M. bovis P22, and the expression of selected immune response genes were determined and analyzed as possible correlates of protection. We demonstrated that oral immunization with the SUB+IV formulation resulted in 51% reduction in the number of female ticks and 30% reduction in fertility with an overall efficacy of 65% in the control of R. microplus infestations by considering the cumulative effect on reducing tick survival and fertility in cattle. The akr2, IL-1ß, and C3 mRNA levels together with antibody levels against SUB correlated with vaccine efficacy. The effect of the oral immunization with SUB+IV in cattle on tick survival and fertility is essential to reduce tick infestations, and extended previous results on the effect of R. microplus SUB for the control of cattle tick infestations. These results support the development of oral vaccines formulations for the control of tick infestations and the incidence of tick-borne diseases.


Assuntos
Antígenos/administração & dosagem , Antígenos/imunologia , Proteínas de Artrópodes/administração & dosagem , Proteínas de Artrópodes/imunologia , Mycobacterium bovis/imunologia , Rhipicephalus/crescimento & desenvolvimento , Rhipicephalus/imunologia , Infestações por Carrapato/prevenção & controle , Vacinação/métodos , Administração Oral , Animais , Bovinos , Modelos Animais de Doenças , Fertilidade , Fatores Imunológicos/análise , Incidência , Análise de Sobrevida , Resultado do Tratamento
20.
PLoS One ; 14(3): e0213536, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30849108

RESUMO

A safe and effective adjuvant is necessary to induce reliable protective efficacy of the protein-based vaccines against tuberculosis (TB). Mycobacterial components, such as synthetic cord factor and arabinogalactan, have been used as one of the adjuvant components. Mycobacterium bovis bacillus Calmette- Guérin cell-wall skeleton (BCG-CWS) has been used as an effective immune-stimulator. However, it is not proven whether BCG-CWS can be an effective adjuvant for the subunit protein vaccine of TB. In this study, we demonstrated that the BCG-CWS effectively coupled with Ag85B and enhanced the conjugated Ag85B activity on the maturation of dendritic cells (DCs). Ag85B-BCG-CWS-matured DCs induced significant Th1 and Th17 responses when compared to BCG-CWS or Ag85B alone. In addition, significant Ag85B-specific Th1 and Th17 responses were induced in Ag85B-BCG-CWS-immunized mice before infection with M. tuberculosis and maintained after infection. Moreover, Ag85B-BCG-CWS showed significant protective effect comparable to live BCG at 6 weeks after infection and maintained its protective efficacy at 32 weeks post-challenge, whereas live BCG did not. These results suggest that the BCG-CWS may be an effective adjuvant candidate for a protein-based vaccine against TB.


Assuntos
Antígenos de Bactérias/imunologia , Parede Celular/imunologia , Mycobacterium bovis/imunologia , Mycobacterium tuberculosis/imunologia , Células Th1/imunologia , Células Th2/imunologia , Vacinas contra a Tuberculose/imunologia , Tuberculose/imunologia , Adjuvantes Imunológicos/farmacologia , Animais , Antígenos de Bactérias/farmacologia , Feminino , Camundongos , Células Th2/patologia , Tuberculose/patologia , Tuberculose/prevenção & controle , Vacinas contra a Tuberculose/farmacologia
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