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1.
Medicine (Baltimore) ; 98(23): e15977, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31169732

RESUMO

BACKGROUND: Tuberculosis (TB) is a highly contagious and chronic disease. The microbiological examination to confirm children TB disease are limited due to paucibacillary Mycobacterium, specimens and detecting facilities. Considering these limitations in diagnosing children TB, new and reliable methods that detect children TB should be developed. Recently, Interferon gamma-induced protein 10 (IP-10) has been identified as a sensitive parameter in detecting children TB. The present study aims to synthesis and analysis the diagnostic value of IP-10 for children TB. METHODS: We will search PubMed, Embase, the Cochrane Library, Web of Science, Chinese National Knowledge Infrastructure, and Chinese Biological Medical Databases. We will search relevant citations up to May 2019. The quality of individual study will be assessed using the Quality Assessment of Diagnostic Accuracy Studies tool-2 (QUADAS-2). Stata 14.0 software will be used to calculate the pooled sensitivity, pooled specificity, pooled positive likelihood ratio (PLR), pooled negative likelihood ratio (NLR), pooled diagnostic odds ratio (DOR), pre-test probability, post-test probability and the hierarchical summary receiver operating characteristic (HSROC) curve. RESULTS: The results of this study will be published in a peer-reviewed journal. DISCUSSION: The evidence will indicate that IP-10 test is an alternative immunological test in detecting children TB. This is a protocol of systematic review and meta-analysis, so the ethical approval and patient consent are not required. PROTOCOL REGISTRATION NUMBER: CRD42019129743.


Assuntos
Quimiocina CXCL10/análise , Testes Imunológicos/estatística & dados numéricos , Mycobacterium/imunologia , Tuberculose Pulmonar/diagnóstico , Adolescente , Estudos de Casos e Controles , Criança , Pré-Escolar , Estudos de Coortes , Feminino , Humanos , Testes Imunológicos/métodos , Lactente , Funções Verossimilhança , Masculino , Metanálise como Assunto , Projetos de Pesquisa , Sensibilidade e Especificidade , Revisão Sistemática como Assunto , Tuberculose Pulmonar/imunologia
2.
Psychopharmacology (Berl) ; 236(5): 1653-1670, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-31119329

RESUMO

RATIONALE: Mycobacterium vaccae (NCTC 11659) is an environmental saprophytic bacterium with anti-inflammatory, immunoregulatory, and stress resilience properties. Previous studies have shown that whole, heat-killed preparations of M. vaccae prevent allergic airway inflammation in a murine model of allergic asthma. Recent studies also demonstrate that immunization with M. vaccae prevents stress-induced exaggeration of proinflammatory cytokine secretion from mesenteric lymph node cells stimulated ex vivo, prevents stress-induced exaggeration of chemically induced colitis in a model of inflammatory bowel disease, and prevents stress-induced anxiety-like defensive behavioral responses. Furthermore, immunization with M. vaccae induces anti-inflammatory responses in the brain and prevents stress-induced exaggeration of microglial priming. However, the molecular mechanisms underlying anti-inflammatory effects of M. vaccae are not known. OBJECTIVES: Our objective was to identify and characterize novel anti-inflammatory molecules from M. vaccae NCTC 11659. METHODS: We have purified and identified a unique anti-inflammatory triglyceride, 1,2,3-tri [Z-10-hexadecenoyl] glycerol, from M. vaccae and evaluated its effects in freshly isolated murine peritoneal macrophages. RESULTS: The free fatty acid form of 1,2,3-tri [Z-10-hexadecenoyl] glycerol, 10(Z)-hexadecenoic acid, decreased lipopolysaccharide-stimulated secretion of the proinflammatory cytokine IL-6 ex vivo. Meanwhile, next-generation RNA sequencing revealed that pretreatment with 10(Z)-hexadecenoic acid upregulated genes associated with peroxisome proliferator-activated receptor alpha (PPARα) signaling in lipopolysaccharide-stimulated macrophages, in association with a broad transcriptional repression of inflammatory markers. We confirmed using luciferase-based transfection assays that 10(Z)-hexadecenoic acid activated PPARα signaling, but not PPARγ, PPARδ, or retinoic acid receptor (RAR) α signaling. The effects of 10(Z)-hexadecenoic acid on lipopolysaccharide-stimulated secretion of IL-6 were prevented by PPARα antagonists and absent in PPARα-deficient mice. CONCLUSION: Future studies should evaluate the effects of 10(Z)-hexadecenoic acid on stress-induced exaggeration of peripheral inflammatory signaling, central neuroinflammatory signaling, and anxiety- and fear-related defensive behavioral responses.


Assuntos
Anti-Inflamatórios/imunologia , Anti-Inflamatórios/isolamento & purificação , Mycobacterium/imunologia , Mycobacterium/isolamento & purificação , Estresse Psicológico/imunologia , Estresse Psicológico/prevenção & controle , Animais , Ansiedade/induzido quimicamente , Ansiedade/imunologia , Ansiedade/prevenção & controle , Colite/induzido quimicamente , Colite/imunologia , Colite/prevenção & controle , Medo/efeitos dos fármacos , Medo/fisiologia , Inflamação/imunologia , Inflamação/prevenção & controle , Lipopolissacarídeos/toxicidade , Macrófagos/efeitos dos fármacos , Macrófagos/imunologia , Masculino , Camundongos , Camundongos da Linhagem 129 , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Microglia/efeitos dos fármacos , Microglia/imunologia , Microbiologia do Solo , Estresse Psicológico/induzido quimicamente
3.
Am J Trop Med Hyg ; 100(6): 1401-1406, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-30994092

RESUMO

Lymph node tuberculosis (LNTB) is characterized by the enhanced baseline and antigen-specific production of type 1/17 cytokines and reduced baseline and antigen-specific production of interleukin (IL)-1ß and IL-18 at the site of infection when compared with peripheral blood. However, the cytokine profile in the lymph nodes (LNs) of Mycobacterium tuberculosis culture-positive LNTB (LNTB+) and negative LNTB (LNTB-) has not been examined. To address this, we have examined the baseline and mycobacterial antigen-stimulated cytokine levels of type 1 (interferon gamma [IFNγ], tumor necrosis factor alpha [TNFα], IL-2), type 2 (IL-4, IL-5, and IL-13), type 17 (IL-17A, IL-17F, and IL-22), pro-inflammatory (IL-1α, IL-1ß, IL-18, and granulocyte macrophage colony-stimulating factor [GM-CSF]), and regulatory cytokines (IL-10, transforming growth factor beta [TGF-ß]) cytokines in the LN culture supernatants of LNTB+ and LNTB- individuals. We have observed significantly enhanced baseline levels of IL-13 and IL-10 and significantly reduced baseline levels of IL-4 and GM-CSF in LNTB+ individuals compared with LNTB- individuals. By contrast, we have observed significantly enhanced levels of type 1 (IFNγ, TNFα, and IL-2), type 17 (IL-17F and IL-22), and pro-inflammatory (IL-1α and GM-CSF) cytokines and significantly reduced levels of TGFß in response to purified protein derivative, early secreted antigen-6, and culture filtrate protein-10 antigens in LNTB+ compared with LNTB- individuals. On phorbol 12-myristate 13-acetate/ionomycin stimulation, no significant difference was observed for any of the cytokines examined. Thus, our study revealed several interesting differences in the cytokine profiles of mycobacterial antigen-stimulated LN cultures in LNTB+ and LNTB- individuals. Therefore, we suggest the presence of mycobacteria plays a significant role in driving the cytokine response at the site of infection in LNTB.


Assuntos
Antígenos de Bactérias/imunologia , Citocinas/metabolismo , Mycobacterium/imunologia , Tuberculose dos Linfonodos/imunologia , Adolescente , Adulto , Feminino , Humanos , Inflamação/imunologia , Masculino , Pessoa de Meia-Idade , Adulto Jovem
4.
Zhonghua Jie He He Hu Xi Za Zhi ; 42(4): 262-267, 2019 Apr 12.
Artigo em Chinês | MEDLINE | ID: mdl-30955283

RESUMO

Objective: The aim of this study was to determine the performance of the ratio of tuberculosis-specific antigen (TBAg) to phytohemagglutinin (PHA) (TBAg/PHA ratio) in T-SPOT assay in the diagnosis of active tuberculosis (ATB). Methods: Between January 2014 and January 2017, 378 Mycobacterium tuberculosis (MTB) culture positive patients (268 cases of pulmonary tuberculosis, 110 extra-pulmonary tuberculosis) and 824 healthy individuals were recruited from Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology. T-SPOT assay was performed and TBAg/PHA ratio was calculated in all the participants. To validate the study, another group of 223 MTB culture positive TB patients with positive T-SPOT results were recruited from Guangzhou Chest Hospital between January 2017 and December 2017. This was a retrospective case-control study and differences between groups were analyzed using the Mann-Whitney U-test. Results: Of the 378 culture positive ATB patients, 344 patients had positive T-SPOT results. Of the 824 healthy individuals, 204 individuals had positive T-SPOT results. Using healthy individuals as the control group, the sensitivity and specificity of T-SPOT assay in the diagnosis of ATB were 91.0% (344/378) and 75.2% (620/824). Directly using T-SPOT results had a limited accuracy in distinguishing ATB from latent tuberculosis infection (LTBI). The area under the receiver operating characteristic (ROC) curve was between 0.7 and 0.8. However, a further calculation of the TBAg/PHA ratio showed a better performance than TBAg in distinguishing these two conditions, and the area under the ROC curve was 0.881 (95% CI: 0.853-0.909). If using the threshold value of 0.234, the sensitivity and specificity of the TBAg/PHA ratio in distinguishing ATB from LTBI were 69.5% (239/344) and 94.12% (192/204). The validation data showed that the performance of the TBAg/PHA ratio in distinguishing ATB from LTBI was also satisfactory, and the area under the ROC curve was 0.901 (95% CI: 0.872-0.931). Furthermore, the TBAg/PHA ratio had an important role in the diagnosis of extra-pulmonary tuberculosis. If using the threshold value of 0.234, the sensitivity and specificity of the TBAg/PHA ratio in the diagnosis of extra-pulmonary tuberculosis were 79.2% (76/96) and 94.1% (192/204). The area under the ROC curve was 0.932 (95% CI: 0.897-0.967). Conclusions: The TBAg/PHA ratio in T-SPOT assay was better than directly using T-SPOT results in distinguishing ATB from LTBI. This ratio also showed a potential use in the diagnosis of extra-pulmonary tuberculosis.


Assuntos
Antígenos de Bactérias/análise , Tuberculose Latente/diagnóstico , Mycobacterium tuberculosis/isolamento & purificação , Mycobacterium/imunologia , Fito-Hemaglutininas/análise , Tuberculose/diagnóstico , Estudos de Casos e Controles , Feminino , Humanos , Interferon gama , Tuberculose Latente/microbiologia , Masculino , Curva ROC , Estudos Retrospectivos , Sensibilidade e Especificidade , Tuberculose/microbiologia
5.
Tuberculosis (Edinb) ; 115: 14-23, 2019 03.
Artigo em Inglês | MEDLINE | ID: mdl-30948168

RESUMO

A collection of over 1600 sequenced bacteriophages isolated on a single host strain, Mycobacterium smegmatis mc2155, can be grouped into over two dozen types that have little or no nucleotide sequence similarity to each other. One group, Cluster K, can be divided into several subclusters, and the well-characterized and much exploited phage TM4 lies in Subcluster K2. Many of the Cluster K phages have broad host ranges and infect both fast- and slow-growing mycobacterial strains. Here we describe phage ZoeJ, a new Subcluster K2 member, which infects a broad spectrum of mycobacterial hosts including M. smegmatis, Mycobacterium tuberculosis, and Mycobacterium avium. ZoeJ has extensive sequence similarity to TM4, and comparative analysis reveals the precise deletion conferring the lytic phenotype of TM4. The ZoeJ immunity repressor was identified as gene 45, which is prophage-expressed, is required for lysogeny, and is sufficient to confer superinfection immunity to ZoeJ. ZoeJ gp45 also confers immunity to Subcluster K2 phage Milly, and Subcluster K1 phages Adephagia and CrimD, but surprisingly not to TM4. RNAseq analysis reveals the temporal pattern of early and late gene expressions in ZoeJ lytic growth and suggests a role for the ESAS motifs for gene regulation.


Assuntos
Genoma Bacteriano/genética , Micobacteriófagos/genética , Mycobacterium/genética , Proteínas de Bactérias/genética , DNA Bacteriano/genética , Genes Bacterianos/genética , Interações Hospedeiro-Patógeno , Imunidade Celular/genética , Imunidade Celular/imunologia , Micobacteriófagos/imunologia , Micobacteriófagos/patogenicidade , Mycobacterium/imunologia , Mycobacterium/patogenicidade , Mycobacterium tuberculosis/genética , Mycobacterium tuberculosis/imunologia , Mycobacterium tuberculosis/patogenicidade , Plasmídeos/genética , Proteínas Recombinantes , Sequenciamento Completo do Genoma
6.
Cell Immunol ; 335: 85-92, 2019 01.
Artigo em Inglês | MEDLINE | ID: mdl-30527747

RESUMO

Lipoarabinomannan (LAM) is an important virulent factor secreted by mycobacteria, which generally elicit a strong immune response in the host. In this study, the structural difference of LAMs from three mycobacterial strains, Mycobacterium tuberculosis H37Rv, Mycobacterium smegmatis mc2155 and a newly discovered clinical isolate, M. sp. QGD101, was analyzed and further evaluated whether these LAMs can induce DC maturation and promote the immunomodulatory properties. The results reveal that the major structural difference of these LAMs is the amount of mannosyl residues, especially at the terminal end of LAM, which play a key role in determining the divergent response of DCs after mycobacterial infection. Also, this study indicates an important relevance between the glycosylated structure of LAM and its immunomodulatory property, which is helpful to develop a potential approach for identification of different mycobacteria and also lays a foundation for the development of a novel polysaccharide immunological strategy against tuberculosis.


Assuntos
Células Dendríticas/imunologia , Lipopolissacarídeos/metabolismo , Mycobacterium/metabolismo , Animais , Citocinas/análise , Citocinas/imunologia , Células Dendríticas/metabolismo , Feminino , Humanos , Lipopolissacarídeos/química , Lipopolissacarídeos/imunologia , Macrófagos/imunologia , Camundongos , Camundongos Endogâmicos C57BL , Mycobacterium/imunologia , Mycobacterium smegmatis/imunologia , Mycobacterium tuberculosis/imunologia , Tuberculose/imunologia
7.
Sci Immunol ; 3(30)2018 12 21.
Artigo em Inglês | MEDLINE | ID: mdl-30578351

RESUMO

Hundreds of patients with autosomal recessive, complete IL-12p40 or IL-12Rß1 deficiency have been diagnosed over the last 20 years. They typically suffer from invasive mycobacteriosis and, occasionally, from mucocutaneous candidiasis. Susceptibility to these infections is thought to be due to impairments of IL-12-dependent IFN-γ immunity and IL-23-dependent IL-17A/IL-17F immunity, respectively. We report here patients with autosomal recessive, complete IL-12Rß2 or IL-23R deficiency, lacking responses to IL-12 or IL-23 only, all of whom, unexpectedly, display mycobacteriosis without candidiasis. We show that αß T, γδ T, B, NK, ILC1, and ILC2 cells from healthy donors preferentially produce IFN-γ in response to IL-12, whereas NKT cells and MAIT cells preferentially produce IFN-γ in response to IL-23. We also show that the development of IFN-γ-producing CD4+ T cells, including, in particular, mycobacterium-specific TH1* cells (CD45RA-CCR6+), is dependent on both IL-12 and IL-23. Last, we show that IL12RB1, IL12RB2, and IL23R have similar frequencies of deleterious variants in the general population. The comparative rarity of symptomatic patients with IL-12Rß2 or IL-23R deficiency, relative to IL-12Rß1 deficiency, is, therefore, due to lower clinical penetrance. There are fewer symptomatic IL-23R- and IL-12Rß2-deficient than IL-12Rß1-deficient patients, not because these genetic disorders are rarer, but because the isolated absence of IL-12 or IL-23 is, in part, compensated by the other cytokine for the production of IFN-γ, thereby providing some protection against mycobacteria. These experiments of nature show that human IL-12 and IL-23 are both required for optimal IFN-γ-dependent immunity to mycobacteria, both individually and much more so cooperatively.


Assuntos
Imunidade Inata/imunologia , Interferon gama/imunologia , Interleucina-12/imunologia , Interleucina-23/imunologia , Infecções por Micobactéria não Tuberculosa/imunologia , Mycobacterium/imunologia , Humanos , Interleucina-12/deficiência , Interleucina-12/genética , Interleucina-23/deficiência , Interleucina-23/genética , Linhagem
8.
Indian J Tuberc ; 65(4): 335-344, 2018 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-30522622

RESUMO

INTRODUCTION: The need to shorten the treatment duration in tuberculosis has always been felt. Immunotherapy in combination with chemotherapy has been considered a promising approach for this purpose into tuberculosis. We studied the adjuvant immunotherapeutic activity of Mycobacterium indicus pranii (MIP or Mw) in combination with conventional chemotherapy using guinea pig of pulmonary tuberculosis infected with Mycobacterium tuberculosis H37Rv via aerosol. METHODS: Experimental animals treated with standard chemotherapy and immunotherapy (MIP) separately and in combination of both. Guinea pig lungs evaluated following infection and subsequent therapy at predefine time point. Various cytokine mRNA expressions levels were quantified by quantitative reverse transcriptase PCR at the 4th, 8th and 12th week post-infection of M. tuberculosis. RESULTS: We determined the time required for bacterial clearance from guinea pig lungs. Standard chemotherapy (RvCh) compared to the animals where chemotherapy plus Mw immunotherpay (RvChMwT) was given. It took 12 weeks to achieve bacterial clearance in the RvCh group while this was achieved in 8 weeks in RvChMwT group. Pro-inflammatory cytokines (IFN-γ, IL-2, IL-12p35 and TNF-α) level were higher in RvCh, RvChMwT and RvMwT group, while the IL-10 and TGF-ß were suppressed. CONCLUSION: Cytokine expression level showed that Mw in conjunction with chemotherapy enhances the effect of pro-inflammatory cytokines (such as, IFN-γ, IL-2, IL-12 and TNF-α) and reduces the production and effect of anti-inflammatory cytokines (like IL-10 and TGF-ß) thereby restoring the pro-inflammatory / anti-inflammatory cytokines balance. Thus, the present study indicates that subject to rigorous testing by other parameters, Mw (MIP) as adjunct immunotherapy has potential for reducing treatment duration.


Assuntos
Antituberculosos/uso terapêutico , Mycobacterium/imunologia , Tuberculose Pulmonar/terapia , Aerossóis , Animais , Antituberculosos/administração & dosagem , Citocinas/genética , Modelos Animais de Doenças , Quimioterapia Combinada , Feminino , Regulação da Expressão Gênica , Cobaias , Imunoterapia , Reação em Cadeia da Polimerase , RNA Mensageiro/análise , Tuberculose Pulmonar/tratamento farmacológico
9.
Toxins (Basel) ; 10(11)2018 Nov 14.
Artigo em Inglês | MEDLINE | ID: mdl-30441856

RESUMO

Staphylococcus aureus is a nosocomial pathogen that can cause chronic to persistent infections. Among different mediators of pathogenesis, toxin-antitoxin (TA) systems are emerging as the most prominent. These systems are frequently studied in Escherichia coli and Mycobacterial species but rarely explored in S. aureus. In the present study, we thoroughly analyzed the S. aureus genome and screened all possible TA systems using the Rasta bacteria and toxin-antitoxin database. We further searched E. coli and Mycobacterial TA homologs and selected 67 TA loci as putative TA systems in S. aureus. The host inhibition of growth (HigBA) TA family was predominantly detected in S. aureus. In addition, we detected seven pathogenicity islands in the S. aureus genome that are enriched with virulence genes and contain 26 out of 67 TA systems. We ectopically expressed multiple TA genes in E. coli and S. aureus that exhibited bacteriostatic and bactericidal effects on cell growth. The type I Fst toxin created holes in the cell wall while the TxpA toxin reduced cell size and induced cell wall septation. Besides, we identified a new TA system whose antitoxin functions as a transcriptional autoregulator while the toxin functions as an inhibitor of autoregulation. Altogether, this study provides a plethora of new as well as previously known TA systems that will revitalize the research on S. aureus TA systems.


Assuntos
Toxinas Bacterianas/genética , Toxinas Bacterianas/imunologia , Staphylococcus aureus/genética , Staphylococcus aureus/imunologia , Sistemas Toxina-Antitoxina/genética , Biologia Computacional , Escherichia coli/genética , Escherichia coli/imunologia , Mycobacterium/genética , Mycobacterium/imunologia
10.
FEBS Lett ; 592(23): 3921-3942, 2018 12.
Artigo em Inglês | MEDLINE | ID: mdl-30320884

RESUMO

Lipid rafts formed by glycosphingolipids (GSLs) on cellular membranes play important roles in innate and adaptive immunity. Lactosylceramide (LacCer) forms lipid rafts on plasma and granular membranes of human neutrophils. These LacCer-enriched lipid rafts bind directly to pathogenic components, such as pathogenic fungi-derived ß-glucan and Mycobacteria-derived lipoarabinomannan via carbohydrate-carbohydrate interactions, and mediate innate immune responses to these pathogens. In contrast, a-series and o-series gangliosides form distinct rafts on CD4+ and CD8+ T cell subsets, respectively, contributing to the respective functions of these cells and stimulating adaptive immune responses through T cell receptors. These findings suggest that gangliosides play indispensable roles in T cell selection and activation. This Review introduces the involvement of GSL-enriched lipid rafts in innate and adaptive immunity.


Assuntos
Fungos/imunologia , Glicoesfingolipídeos/imunologia , Sistema Imunitário/imunologia , Microdomínios da Membrana/imunologia , Mycobacterium/imunologia , Animais , Fungos/metabolismo , Fungos/fisiologia , Glicoesfingolipídeos/metabolismo , Humanos , Sistema Imunitário/metabolismo , Sistema Imunitário/microbiologia , Lipopolissacarídeos/imunologia , Lipopolissacarídeos/metabolismo , Microdomínios da Membrana/metabolismo , Microdomínios da Membrana/microbiologia , Mycobacterium/metabolismo , Mycobacterium/fisiologia , Neutrófilos/imunologia , Neutrófilos/metabolismo , Neutrófilos/microbiologia , beta-Glucanas/imunologia , beta-Glucanas/metabolismo
13.
J Immunol ; 201(5): 1478-1490, 2018 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-30061197

RESUMO

In developed countries, pulmonary nontuberculous mycobacteria (NTM) infections are more prevalent than Mycobacterium tuberculosis infections. Given the differences in the pathogenesis of NTM and M. tuberculosis infections, separate studies are needed to investigate the pathological effects of NTM pathogens. Our previous study showed that anti-IFN-γ autoantibodies are detected in NTM-infected patients. However, the role of NK cells and especially NK cell-derived IFN-γ in this context has not been studied in detail. In the current study, we show that NK1.1 cell depletion increases bacterial load and mortality in a mouse model of pulmonary NTM infection. NK1.1 cell depletion exacerbates NTM-induced pathogenesis by reducing macrophage phagocytosis, dendritic cell development, cytokine production, and lung granuloma formation. Similar pathological phenomena are observed in IFN-γ-deficient (IFN-γ-/-) mice following NTM infection, and adoptive transfer of wild-type NK cells into IFN-γ-/- mice considerably reduces NTM pathogenesis. Injection of rIFN-γ also prevents NTM-induced pathogenesis in IFN-γ-/- mice. We observed that NK cells represent the main producers of IFN-γ in the lungs and production starts as soon as 1 d postinfection. Accordingly, injection of rIFN-γ into IFN-γ-/- mice 1 d (but not 2 wk) postinfection significantly improves immunity against NTM infection. NK cells also stimulate mycobacterial killing and IL-12 production by macrophages. Our results therefore indicate that IFN-γ production by NK cells plays an important role in activating and enhancing innate and adaptive immune responses at early stages of pulmonary NTM infection.


Assuntos
Imunidade Inata , Interferon gama/imunologia , Células Matadoras Naturais/imunologia , Pulmão/imunologia , Infecções por Micobactéria não Tuberculosa/imunologia , Mycobacterium/imunologia , Pneumonia Bacteriana/imunologia , Imunidade Adaptativa/genética , Animais , Interferon gama/deficiência , Interleucina-12/genética , Interleucina-12/imunologia , Células Matadoras Naturais/patologia , Pulmão/microbiologia , Pulmão/patologia , Camundongos , Camundongos Knockout , Infecções por Micobactéria não Tuberculosa/genética , Infecções por Micobactéria não Tuberculosa/patologia , Pneumonia Bacteriana/patologia
14.
Neurobiol Aging ; 71: 105-114, 2018 11.
Artigo em Inglês | MEDLINE | ID: mdl-30118926

RESUMO

Aging is a major risk factor for developing postoperative cognitive dysfunction. Neuroinflammatory processes, which can play a causal role in the etiology of postoperative cognitive dysfunction, are potentiated or primed as a function of aging. Here we explored whether exposure to a microorganism with immunoregulatory and anti-inflammatory properties, Mycobacterium vaccae NCTC 11659 (M. vaccae), could ameliorate age-associated neuroinflammatory priming. Aged (24 months) and adult (3 months) male F344XBN rats were immunized with heat-killed M. vaccae (3 injections, once per week) before undergoing a laparotomy or anesthesia control procedure. Aged, but not young rats, showed postoperative learning/memory deficits in a fear-conditioning paradigm. Importantly, M. vaccae immunization protected aged rats from these surgery-induced cognitive impairments. M. vaccae immunization also shifted the aged proinflammatory hippocampal microenvironment toward an anti-inflammatory phenotype. Furthermore, M. vaccae immunization reduced age-related hyperinflammatory responses in isolated hippocampal microglia. Overall, our novel data suggest that M. vaccae can induce an anti-inflammatory milieu in the aged brain and thus mitigate the neuroinflammatory and cognitive impairments induced by surgery.


Assuntos
Vacinas Bacterianas/administração & dosagem , Disfunção Cognitiva/imunologia , Disfunção Cognitiva/cirurgia , Encefalite/imunologia , Encefalite/cirurgia , Mycobacterium/imunologia , Animais , Disfunção Cognitiva/prevenção & controle , Encefalite/prevenção & controle , Hipocampo/imunologia , Imunização , Masculino , Memória , Microglia/imunologia , Ratos Endogâmicos F344 , Vacinas de Produtos Inativados/administração & dosagem
15.
Microbiol Immunol ; 62(8): 531-540, 2018 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-29989252

RESUMO

Allergen-specific immunotherapy to induce T regulatory cells in the periphery has been used to treat allergic diseases. Mycobacteria can be used as an adjuvant for inducing T regulatory cells. However, it is unclear whether intranasal immunotherapy in combination with Mycobacteria adjuvant induces regulatory T cell differentiation and attenuates allergic responses in vivo. To investigate the role of intranasal ovalbumin (OVA) treatment alone and in combination with Mycobacteria vaccae, proportions of FoxP3+ regulatory T cells and anti-inflammatory responses were evaluated in a murine model of asthma that was established in three groups of bicistronic Foxp3EGFP reporter BALB/c mice. Before establishment of the asthma model, two groups of mice received intranasal OVA immunotherapy and one also received simultaneous s.c. M. vaccae. Expression of CD4+ CD25+ Foxp3+EGFP+ T cells in the lung and spleen was analyzed by flow cytometry and the cytokine profiles of allergen-stimulated lung and spleen lymphocytes assessed. The intranasal OVA immunotherapy group showed greater expression of CD4+ CD25+ Foxp3+EGFP+ T cells in the spleen whereas in the group that also received M. vaccae such greater expression was demonstrated in the lung. Additionally, the proportion of IL-10 and IFN-γ-secreting splenocytes was greater in the intranasal OVA + M. vaccae group. CD25 neutralization decreased CD4+ Foxp3+ cells more than other groups. In parallel with this finding, production of IL-10 and IFN-γ was down-regulated. Mucosal administration of OVA antigen results in a greater proportion of CD4+ Foxp3+ T cells in the spleen. IL-10 and IFN-γ induced by intranasal OVA immunotherapy and M. vaccae administration is down-regulated after CD25 neutralization.


Assuntos
Adjuvantes Imunológicos , Administração Intranasal/métodos , Imunoterapia/métodos , Pulmão/imunologia , Mycobacterium/imunologia , Ovalbumina/imunologia , Linfócitos T Reguladores/imunologia , Administração através da Mucosa , Alérgenos/imunologia , Animais , Asma/imunologia , Asma/prevenção & controle , Linfócitos T CD4-Positivos/imunologia , Diferenciação Celular , Citocinas/biossíntese , Dessensibilização Imunológica , Modelos Animais de Doenças , Regulação para Baixo , Fatores de Transcrição Forkhead/imunologia , Proteínas de Fluorescência Verde , Tolerância Imunológica/imunologia , Imunidade nas Mucosas/imunologia , Imunoglobulina E/sangue , Imunoglobulina G/sangue , Interferon gama/biossíntese , Interleucina-10/biossíntese , Subunidade alfa de Receptor de Interleucina-2 , Camundongos , Camundongos Endogâmicos BALB C , Baço/imunologia
16.
J Immunol ; 201(5): 1421-1433, 2018 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-30037848

RESUMO

Phagosome maturation is an important innate defense mechanism of macrophages against bacterial infections. The mycobacterial secretory protein kinase G (PknG), a serine/threonine kinase, is known to block phagosome-lysosome (P-L) fusion, and the kinase activity of PknG appears to be crucial for this. However, the detail mechanisms are not well understood. In the current study, we demonstrate that PknG of Mycobacterium sp interacts with the human Rab GTPase protein, Rab7l1, but not with other Rab proteins as well as factors like Rabaptin, Rabex5, PI3K3, Mon1a, Mon1b, early endosome autoantigen 1, and LAMP2 that are known to play crucial roles in P-L fusion. The Rab7l1 protein is shown to play a role in P-L fusion during mycobacterial infection, and its absence promotes survival of bacilli inside macrophages. PknG was found to be translocated to the Golgi complex where it interacted with GDP-bound Rab7l1 and blocked transition of inactive Rab7l1-GDP to active Rab7l1-GTP, resulting in inhibition of recruitment of Rab7l1-GTP to bacilli-containing phagosomes, and these processes are dependent on the kinase activity of PknG. Localization of Rab7l1-GTP to phagosomes was found to be critical for the subsequent recruitment of other phago-lysosomal markers like early endosome autoantigen 1, Rab7, and LAMP2 during infection. Thus, by interfering with the Rab7l1 signaling process, PknG prevents P-L fusion and favors bacterial survival inside human macrophages. This study highlights a novel role of Rab7l1 in the phagosomal maturation process and hints at unique strategies of mycobacteria used to interfere with Rab7l1 function to favor its survival inside human macrophages.


Assuntos
Proteínas de Bactérias/imunologia , Proteínas Quinases Dependentes de GMP Cíclico/imunologia , Lisossomos/imunologia , Macrófagos/imunologia , Mycobacterium/imunologia , Fagocitose , Fagossomos/imunologia , Transdução de Sinais/imunologia , Proteínas de Bactérias/genética , Proteínas Quinases Dependentes de GMP Cíclico/genética , Células HEK293 , Humanos , Lisossomos/genética , Lisossomos/microbiologia , Macrófagos/microbiologia , Macrófagos/patologia , Fusão de Membrana/imunologia , Mycobacterium/genética , Fagossomos/genética , Fagossomos/microbiologia , Fagossomos/patologia , Células THP-1 , Proteínas rab1 de Ligação ao GTP
17.
Genome Biol Evol ; 10(8): 1858-1874, 2018 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-30010947

RESUMO

Mycobacterium africanum consists of Lineages L5 and L6 of the Mycobacterium tuberculosis complex (MTBC) and causes human tuberculosis in specific regions of Western Africa, but is generally not transmitted in other parts of the world. Since M. africanum is evolutionarily closely placed between the globally dispersed Mycobacterium tuberculosis and animal-adapted MTBC-members, these lineages provide valuable insight into M. tuberculosis evolution. Here, we have collected 15 M. africanum L5 strains isolated in France over 4 decades. Illumina sequencing and phylogenomic analysis revealed a previously underappreciated diversity within L5, which consists of distinct sublineages. L5 strains caused relatively high levels of extrapulmonary tuberculosis and included multi- and extensively drug-resistant isolates, especially in the newly defined sublineage L5.2. The specific L5 sublineages also exhibit distinct phenotypic characteristics related to in vitro growth, protein secretion and in vivo immunogenicity. In particular, we identified a PE_PGRS and PPE-MPTR secretion defect specific for sublineage L5.2, which was independent of PPE38. Furthermore, L5 isolates were able to efficiently secrete and induce immune responses against ESX-1 substrates contrary to previous predictions. These phenotypes of Type VII protein secretion and immunogenicity provide valuable information to better link genome sequences to phenotypic traits and thereby understand the evolution of the MTBC.


Assuntos
Proteínas de Bactérias/metabolismo , Farmacorresistência Bacteriana/genética , Genômica , Mycobacterium/genética , Mycobacterium/imunologia , Filogenia , Adulto , Animais , Pareamento de Bases/genética , Biologia Computacional , Farmacorresistência Bacteriana/efeitos dos fármacos , Feminino , Marcadores Genéticos , Genótipo , Humanos , Isoniazida/farmacologia , Masculino , Camundongos Endogâmicos C57BL , Pessoa de Meia-Idade , Mycobacterium/efeitos dos fármacos , Mycobacterium/isolamento & purificação , Fenótipo , Deleção de Sequência/genética , Linfócitos T/efeitos dos fármacos , Linfócitos T/imunologia
18.
Methods Mol Biol ; 1808: 143-150, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29956180

RESUMO

Enzyme-linked immunospot (ELISPOT) is an assay used to detect secretion of cytokines from immune cells. The resolution and sensitivity of ELISPOT allow for the detection of rare T cell specificities and small quantities of molecules produced by individual cells. In this chapter, we describe an epitope screening method that uses CD4+ T cell ELISPOT assays to identify specific novel mycobacterial antigens as potential vaccine candidates. In order to screen a large number of candidate epitopes simultaneously, pools of predicted MHC class II peptides were used to identify mycobacterial specific CD4+ T cells. Using this method, we identified novel mycobacterial antigens as vaccine candidates.


Assuntos
Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD4-Positivos/metabolismo , ELISPOT/métodos , Interferon gama/metabolismo , Mycobacterium/imunologia , Animais , Antígenos/imunologia , Epitopos de Linfócito T/imunologia , Antígenos de Histocompatibilidade Classe II/imunologia , Antígenos de Histocompatibilidade Classe II/metabolismo , Camundongos
19.
J Immunol ; 201(3): 888-896, 2018 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-29914888

RESUMO

Human T cells that recognize lipid Ags presented by highly conserved CD1 proteins often express semi-invariant TCRs, but the true diversity of lipid Ag-specific TCRs remains unknown. We use CD1b tetramers and high-throughput immunosequencing to analyze thousands of TCRs from ex vivo-sorted or in vitro-expanded T cells specific for the mycobacterial lipid Ag, glucose monomycolate. Our results reveal a surprisingly diverse repertoire resulting from editing of germline-encoded gene rearrangements analogous to MHC-restricted TCRs. We used a distance-based metric (TCRDist) to show how this diverse TCR repertoire builds upon previously reported conserved motifs by including subject-specific TCRs. In a South African cohort, we show that TCRDist can identify clonal expansion of diverse glucose monomycolate-specific TCRs and accurately distinguish patients with active tuberculosis from control subjects. These data suggest that similar mechanisms govern the selection and expansion of peptide and lipid Ag-specific T cells despite the nonpolymorphic nature of CD1.


Assuntos
Antígenos CD1/imunologia , Lipídeos/imunologia , Receptores de Antígenos de Linfócitos T/imunologia , Tuberculose/imunologia , Adolescente , Linhagem Celular Tumoral , Células Cultivadas , Criança , Feminino , Humanos , Células K562 , Masculino , Mycobacterium/imunologia , Linfócitos T
20.
Brain Behav Immun ; 73: 352-363, 2018 10.
Artigo em Inglês | MEDLINE | ID: mdl-29807129

RESUMO

Exposure to stressors induces anxiety- and depressive-like behaviors, which are mediated, in part, by neuroinflammatory processes. Recent findings demonstrate that treatment with the immunoregulatory and anti-inflammatory bacterium, Mycobacterium vaccae (M. vaccae), attenuates stress-induced exaggeration of peripheral inflammation and stress-induced anxiety-like behavioral responses. However, the effects of M. vaccae on neuroimmune processes have largely been unexplored. In the present study, we examined the effect of M. vaccae NCTC11659 on neuroimmune regulation, stress-induced neuroinflammatory processes and anxiety-like behavior. Adult male rats were immunized 3× with a heat-killed preparation of M. vaccae (0.1 mg, s.c.) or vehicle. M. vaccae induced an anti-inflammatory immunophenotype in hippocampus (increased interleukin (Il)4, Cd200r1, and Mrc1 mRNA expression) and increased IL4 protein 8 d after the last immunization. Central administration of recombinant IL4 recapitulated the effects of M. vaccae on Cd200r1 and Mrc1 mRNA expression. M. vaccae reduced basal levels of genes (Nlrp3 and Nfkbia) involved in microglial priming; thus, we explored the effects of M. vaccae on stress-induced hippocampal microglial priming and HMGB1, which mediates priming. We found that M. vaccae blocked stress-induced decreases in Cd200r1, increases in the alarmin HMGB1, and priming of the microglial response to immune challenge. Furthermore, M. vaccae prevented stress-induced increases in anxiety-like behavior. The present findings suggest that M. vaccae enhances immunomodulation in the CNS and mitigates the neuroinflammatory and behavioral effects of stress, which may underpin its capacity to impart a stress resilient phenotype.


Assuntos
Anti-Inflamatórios/metabolismo , Mycobacterium/imunologia , Estresse Psicológico/metabolismo , Alarminas/imunologia , Alarminas/metabolismo , Animais , Anti-Inflamatórios/farmacologia , Ansiedade/metabolismo , Sistema Nervoso Central/microbiologia , Sistema Nervoso Central/fisiologia , Proteína HMGB1/metabolismo , Hipocampo/imunologia , Imunização/métodos , Inflamação/metabolismo , Masculino , Microglia/metabolismo , Microglia/fisiologia , Proteína 3 que Contém Domínio de Pirina da Família NLR/metabolismo , Ratos , Ratos Sprague-Dawley , Estresse Psicológico/imunologia , Vacinação/métodos
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