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1.
Cell Rep ; 33(13): 108547, 2020 12 29.
Artigo em Inglês | MEDLINE | ID: mdl-33378679

RESUMO

Mycobacterium tuberculosis (Mtb) regulates the macrophage metabolic state to thrive in the host, yet the responsible mechanisms remain elusive. Macrophage activation toward the microbicidal (M1) program depends on the HIF-1α-mediated metabolic shift from oxidative phosphorylation (OXPHOS) toward glycolysis. Here, we ask whether a tuberculosis (TB) microenvironment changes the M1 macrophage metabolic state. We expose M1 macrophages to the acellular fraction of tuberculous pleural effusions (TB-PEs) and find lower glycolytic activity, accompanied by elevated levels of OXPHOS and bacillary load, compared to controls. The eicosanoid fraction of TB-PE drives these metabolic alterations. HIF-1α stabilization reverts the effect of TB-PE by restoring M1 metabolism. Furthermore, Mtb-infected mice with stabilized HIF-1α display lower bacillary loads and a pronounced M1-like metabolic profile in alveolar macrophages (AMs). Collectively, we demonstrate that lipids from a TB-associated microenvironment alter the M1 macrophage metabolic reprogramming by hampering HIF-1α functions, thereby impairing control of Mtb infection.


Assuntos
Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , Lipídeos/farmacologia , Macrófagos/efeitos dos fármacos , Macrófagos/metabolismo , Mycobacterium tuberculosis/metabolismo , Tuberculose Pleural/metabolismo , Animais , Carga Bacteriana , Eicosanoides/farmacologia , Feminino , Glicólise/efeitos dos fármacos , Interações Hospedeiro-Patógeno , Humanos , Ativação de Macrófagos , Camundongos , Camundongos Endogâmicos C57BL , Mitocôndrias/efeitos dos fármacos , Mitocôndrias/metabolismo , Fosforilação Oxidativa/efeitos dos fármacos , Consumo de Oxigênio/efeitos dos fármacos , Derrame Pleural , Tuberculose Pleural/microbiologia
2.
PLoS Pathog ; 16(10): e1008929, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-33002063

RESUMO

The ability of Mycobacterium tuberculosis (Mtb) to persist inside host cells relies on metabolic adaptation, like the accumulation of lipid bodies (LBs) in the so-called foamy macrophages (FM), which are favorable to Mtb. The activation state of macrophages is tightly associated to different metabolic pathways, such as lipid metabolism, but whether differentiation towards FM differs between the macrophage activation profiles remains unclear. Here, we aimed to elucidate whether distinct macrophage activation states exposed to a tuberculosis-associated microenvironment or directly infected with Mtb can form FM. We showed that the triggering of signal transducer and activator of transcription 6 (STAT6) in interleukin (IL)-4-activated human macrophages (M(IL-4)) prevents FM formation induced by pleural effusion from patients with tuberculosis. In these cells, LBs are disrupted by lipolysis, and the released fatty acids enter the ß-oxidation (FAO) pathway fueling the generation of ATP in mitochondria. Accordingly, murine alveolar macrophages, which exhibit a predominant FAO metabolism, are less prone to become FM than bone marrow derived-macrophages. Interestingly, direct infection of M(IL-4) macrophages with Mtb results in the establishment of aerobic glycolytic pathway and FM formation, which could be prevented by FAO activation or inhibition of the hypoxia-inducible factor 1-alpha (HIF-1α)-induced glycolytic pathway. In conclusion, our results demonstrate that Mtb has a remarkable capacity to induce FM formation through the rewiring of metabolic pathways in human macrophages, including the STAT6-driven alternatively activated program. This study provides key insights into macrophage metabolism and pathogen subversion strategies.


Assuntos
Células Espumosas/microbiologia , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , Metabolismo dos Lipídeos , Macrófagos/microbiologia , Mycobacterium tuberculosis/patogenicidade , Animais , Gotículas Lipídicas/metabolismo , Ativação de Macrófagos/fisiologia , Macrófagos/metabolismo , Masculino , Camundongos Endogâmicos BALB C , Mycobacterium tuberculosis/fisiologia , Tuberculose/microbiologia
3.
Infect Genet Evol ; 73: 248-254, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-31077841

RESUMO

The fitness of a pathogen results from the interaction of multiple factors favoring either epidemiological success or failure. Herein, we studied the performance of the M strain, a highly successful multidrug resistant Mycobacterium tuberculosis genotype, and its non-prosperous variant, the 410 strain, in activated human monocyte-derived macrophages. Both strains showed comparable ability to induce necrotic cell death and to survive in apoptotic macrophages. Of the various macrophage activation conditions tested, none led to an enhanced control of the outbreak strain. The combination of 1,25(OH)2 vitaminD3 and IFN-γ favored significantly the control of the non-prosperous 410 strain. These observations indicate that the ability of the M strain to survive within the hostile intracellular milieu is conserved, and the overall fitness cost paid by this genotype would be low. Our results provide additional evidence on bacterial traits that may have contributed to the epidemiological success of the M strain.


Assuntos
Antituberculosos/farmacologia , Epidemias , Macrófagos/fisiologia , Mycobacterium tuberculosis/efeitos dos fármacos , Tuberculose Resistente a Múltiplos Medicamentos/microbiologia , Argentina/epidemiologia , Doadores de Sangue , Morte Celular , Farmacorresistência Bacteriana Múltipla , Humanos , Mycobacterium tuberculosis/genética , Estaurosporina/farmacologia , Tuberculose Resistente a Múltiplos Medicamentos/epidemiologia
4.
Cell Rep ; 26(13): 3586-3599.e7, 2019 03 26.
Artigo em Inglês | MEDLINE | ID: mdl-30917314

RESUMO

The tuberculosis (TB) bacillus, Mycobacterium tuberculosis (Mtb), and HIV-1 act synergistically; however, the mechanisms by which Mtb exacerbates HIV-1 pathogenesis are not well known. Using in vitro and ex vivo cell culture systems, we show that human M(IL-10) anti-inflammatory macrophages, present in TB-associated microenvironment, produce high levels of HIV-1. In vivo, M(IL-10) macrophages are expanded in lungs of co-infected non-human primates, which correlates with disease severity. Furthermore, HIV-1/Mtb co-infected patients display an accumulation of M(IL-10) macrophage markers (soluble CD163 and MerTK). These M(IL-10) macrophages form direct cell-to-cell bridges, which we identified as tunneling nanotubes (TNTs) involved in viral transfer. TNT formation requires the IL-10/STAT3 signaling pathway, and targeted inhibition of TNTs substantially reduces the enhancement of HIV-1 cell-to-cell transfer and overproduction in M(IL-10) macrophages. Our study reveals that TNTs facilitate viral transfer and amplification, thereby promoting TNT formation as a mechanism to be explored in TB/AIDS potential therapeutics.


Assuntos
Infecções por HIV/complicações , Interleucina-10/metabolismo , Macrófagos/patologia , Nanotubos , Fator de Transcrição STAT3/metabolismo , Tuberculose Pulmonar/complicações , Adulto , Idoso , Animais , Células Cultivadas , Coinfecção/patologia , Coinfecção/virologia , Feminino , Infecções por HIV/imunologia , Infecções por HIV/patologia , Infecções por HIV/virologia , Humanos , Macaca mulatta , Ativação de Macrófagos , Macrófagos/virologia , Masculino , Pessoa de Meia-Idade , Mycobacterium tuberculosis , Transdução de Sinais , Tuberculose Pulmonar/imunologia , Tuberculose Pulmonar/patologia , Replicação Viral , Adulto Jovem
6.
Front Immunol ; 9: 1123, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29946317

RESUMO

DC-SIGN (CD209/CLEC4L) is a C-type lectin receptor (CLR) that serves as a reliable cell-surface marker of interleukin 4 (IL-4)-activated human macrophages [M(IL-4)], which historically represent the most studied subset within the M2 spectrum of macrophage activation. Although DC-SIGN plays important roles in Mycobacterium tuberculosis (Mtb) interactions with dendritic cells, its contribution to the Mtb-macrophage interaction remains poorly understood. Since high levels of IL-4 are correlated with tuberculosis (TB) susceptibility and progression, we investigated the role of DC-SIGN in M(IL-4) macrophages in the TB context. First, we demonstrate that DC-SIGN expression is present both in CD68+ macrophages found in tuberculous pulmonary lesions of non-human primates, and in the CD14+ cell population isolated from pleural effusions obtained from TB patients (TB-PE). Likewise, we show that DC-SIGN expression is accentuated in M(IL-4) macrophages derived from peripheral blood CD14+ monocytes isolated from TB patients, or in macrophages stimulated with acellular TB-PE, arguing for the pertinence of DC-SIGN-expressing macrophages in TB. Second, using a siRNA-mediated gene silencing approach, we performed a transcriptomic analysis of DC-SIGN-depleted M(IL-4) macrophages and revealed the upregulation of pro-inflammatory signals in response to challenge with Mtb, as compared to control cells. This pro-inflammatory gene signature was confirmed by RT-qPCR, cytokine/chemokine-based protein array, and ELISA analyses. We also found that inactivation of DC-SIGN renders M(IL-4) macrophages less permissive to Mtb intracellular growth compared to control cells, despite the equal level of bacteria uptake. Last, at the molecular level, we show that DC-SIGN interferes negatively with the pro-inflammatory response and control of Mtb intracellular growth mediated by another CLR, Dectin-1 (CLEC7A). Collectively, this study highlights a dual role for DC-SIGN as, on the one hand, being a host factor granting advantage for Mtb to parasitize macrophages and, on the other hand, representing a molecular switch to turn off the pro-inflammatory response in these cells to prevent potential immunopathology associated to TB.


Assuntos
Moléculas de Adesão Celular/metabolismo , Lectinas Tipo C/metabolismo , Macrófagos/imunologia , Macrófagos/metabolismo , Mycobacterium tuberculosis/imunologia , Receptores de Superfície Celular/metabolismo , Tuberculose/imunologia , Tuberculose/metabolismo , Animais , Moléculas de Adesão Celular/genética , Sobrevivência Celular/genética , Sobrevivência Celular/imunologia , Citocinas/metabolismo , Feminino , Expressão Gênica , Interações Hospedeiro-Patógeno/genética , Interações Hospedeiro-Patógeno/imunologia , Humanos , Mediadores da Inflamação/metabolismo , Lectinas Tipo C/genética , Macaca mulatta , Macrófagos/microbiologia , Monócitos/imunologia , Monócitos/metabolismo , Fagocitose/imunologia , Receptores de Superfície Celular/genética , Tuberculose/genética , Tuberculose/microbiologia
7.
Am J Respir Crit Care Med ; 197(6): 801-813, 2018 03 15.
Artigo em Inglês | MEDLINE | ID: mdl-29161093

RESUMO

RATIONALE: In addition to their well-known function as antibody-producing cells, B lymphocytes can markedly influence the course of infectious or noninfectious diseases via antibody-independent mechanisms. In tuberculosis (TB), B cells accumulate in lungs, yet their functional contribution to the host response remains poorly understood. OBJECTIVES: To document the role of B cells in TB in an unbiased manner. METHODS: We generated the transcriptome of B cells isolated from Mycobacterium tuberculosis (Mtb)-infected mice and validated the identified key pathways using in vitro and in vivo assays. The obtained data were substantiated using B cells from pleural effusion of patients with TB. MEASUREMENTS AND MAIN RESULTS: B cells isolated from Mtb-infected mice displayed a STAT1 (signal transducer and activator of transcription 1)-centered signature, suggesting a role for IFNs in B-cell response to infection. B cells stimulated in vitro with Mtb produced type I IFN, via a mechanism involving the innate sensor STING (stimulator of interferon genes), and antagonized by MyD88 (myeloid differentiation primary response 88) signaling. In vivo, B cells expressed type I IFN in the lungs of Mtb-infected mice and, of clinical relevance, in pleural fluid from patients with TB. Type I IFN expression by B cells induced an altered polarization of macrophages toward a regulatory/antiinflammatory profile in vitro. In vivo, increased provision of type I IFN by B cells in a murine model of B cell-restricted Myd88 deficiency correlated with an enhanced accumulation of regulatory/antiinflammatory macrophages in Mtb-infected lungs. CONCLUSIONS: Type I IFN produced by Mtb-stimulated B cells favors macrophage polarization toward a regulatory/antiinflammatory phenotype during Mtb infection.


Assuntos
Linfócitos B/metabolismo , Interferon Tipo I/metabolismo , Macrófagos/metabolismo , Tuberculose/metabolismo , Animais , Modelos Animais de Doenças , Humanos , Pulmão/metabolismo , Pulmão/microbiologia , Camundongos , Camundongos Endogâmicos C57BL , Mycobacterium tuberculosis , Transdução de Sinais , Baço/metabolismo , Baço/microbiologia
8.
Mediators Inflamm ; 2017: 2810606, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28852268

RESUMO

M strain, the most prevalent multidrug-resistant strain of Mycobacterium tuberculosis (Mtb) in Argentina, has mounted mechanisms to evade innate immune response. The role of human bronchial epithelium in Mtb infection remains unknown as well as its crosstalk with neutrophils (PMN). In this work, we evaluate whether M and H37Rv strains invade and replicate within bronchial epithelial cell line Calu-6 and how conditioned media (CM) derived from infected cells alter PMN responses. We demonstrated that M infects and survives within Calu-6 without promoting death. CM from M-infected Calu-6 (M-CM) did not attract PMN in correlation with its low IL-8 content compared to H37Rv-CM. Also, PMN activation and ROS production in response to irradiated H37Rv were impaired after treatment with M-CM due to the lack of TNF-α. Interestingly, M-CM increased H37Rv replication in PMN which would allow the spreading of mycobacteria upon PMN death and sustain IL-8 release. Thus, our results indicate that even at low invasion/replication rate within Calu-6, M induces the secretion of factors altering the crosstalk between these nonphagocytic cells and PMN, representing an evasion mechanism developed by M strain to persist in the host. These data provide new insights on the role of bronchial epithelium upon M infection.


Assuntos
Interleucina-8/metabolismo , Mycobacterium tuberculosis/efeitos dos fármacos , Neutrófilos/efeitos dos fármacos , Neutrófilos/metabolismo , Fator de Necrose Tumoral alfa/metabolismo , Apoptose/efeitos dos fármacos , Linhagem Celular Tumoral , Quimiocinas/metabolismo , Quimiotaxia/efeitos dos fármacos , Meios de Cultivo Condicionados/farmacologia , Citocinas/metabolismo , Citometria de Fluxo , Humanos , Imunidade Inata/efeitos dos fármacos , Fagocitose/efeitos dos fármacos
9.
Tuberculosis (Edinb) ; 103: 16-23, 2017 03.
Artigo em Inglês | MEDLINE | ID: mdl-28237029

RESUMO

C5a anaphylatoxin is a component of the complement system involved in the modulation of T-cell polarization. Herein we investigated whether C5a receptors, C5aR and C5L2, modulate the cytokine profiles induced by Mycobacterium tuberculosis (Mtb). We analyzed the impact of both receptors on T helper cell polarization induced by the multidrug resistant outbreak strain named M, which is a poor IFN-γ inducer compared with the laboratory strain H37Rv. To this aim, we first blocked C5aR or C5L2 of peripheral blood monocytes (Mo) from patients with tuberculosis and healthy donors, then we stimulated the Mo either with H37Rv or the M strain, and finally we analyzed cytokine profiles of Mo/macrophages (MΦ) and CD4+ T-cells. We found that: (i) Mtb modulated the expression of both C5a receptors, (ii) C5aR inhibited the expansion of CD4+IFN-γ+ lymphocytes stimulated by the M strain but not by H37Rv, (iii) both receptors modulated the Mo/MΦ cytokine expression induced by Mtb. We conclude that C5aR, but not C5L2, plays a role in T helper cell polarization induced by Mtb and that this effect is strain- and donor-dependent. We speculate that the epidemiologically successful M strain takes advantage of this C5aR-mediated inhibition of Th1 polarization to survive within the host.


Assuntos
Citocinas/imunologia , Surtos de Doenças , Mycobacterium tuberculosis/imunologia , Receptor da Anafilatoxina C5a/imunologia , Células Th1/imunologia , Tuberculose Resistente a Múltiplos Medicamentos/imunologia , Adolescente , Adulto , Idoso , Estudos de Casos e Controles , Células Cultivadas , Citocinas/metabolismo , Feminino , Genótipo , Interações Hospedeiro-Patógeno , Humanos , Macrófagos/imunologia , Macrófagos/metabolismo , Macrófagos/microbiologia , Masculino , Pessoa de Meia-Idade , Monócitos/imunologia , Monócitos/metabolismo , Monócitos/microbiologia , Mycobacterium tuberculosis/genética , Mycobacterium tuberculosis/patogenicidade , Fenótipo , Receptor da Anafilatoxina C5a/metabolismo , Receptores de Quimiocinas/imunologia , Receptores de Quimiocinas/metabolismo , Células Th1/metabolismo , Células Th1/microbiologia , Fatores de Tempo , Tuberculose Resistente a Múltiplos Medicamentos/metabolismo , Tuberculose Resistente a Múltiplos Medicamentos/microbiologia , Adulto Jovem
10.
Tuberculosis (Edinb) ; 103: 28-36, 2017 03.
Artigo em Inglês | MEDLINE | ID: mdl-28237031

RESUMO

Globally, about 4.5% of new tuberculosis (TB) cases are multi-drug-resistant (MDR), i.e. resistant to the two most powerful first-line anti-TB drugs. Indeed, 480,000 people developed MDR-TB in 2015 and 190,000 people died because of MDR-TB. The MDR Mycobacterium tuberculosis M family, which belongs to the Haarlem lineage, is highly prosperous in Argentina and capable of building up further drug resistance without impairing its ability to spread. In this study, we sequenced the whole genomes of a highly prosperous M-family strain (Mp) and its contemporary variant, strain 410, which produced only one recorded tuberculosis case in the last two decades. Previous reports have demonstrated that Mp induced dysfunctional CD8+ cytotoxic T cell activity, suggesting that this strain has the ability to evade the immune response against M. tuberculosis. Comparative analysis of Mp and 410 genomes revealed non-synonymous polymorphisms in eleven genes and five intergenic regions with polymorphisms between both strains. Some of these genes and promoter regions are involved in the metabolism of cell wall components, others in drug resistance and a SNP in Rv1861, a gene encoding a putative transglycosylase that produces a truncated protein in Mp. The mutation in Rv3787c, a putative S-adenosyl-l-methionine-dependent methyltransferase, is conserved in all of the other prosperous M strains here analysed and absent in non-prosperous M strains. Remarkably, three polymorphic promoter regions displayed differential transcriptional activity between Mp and 410. We speculate that the observed mutations/polymorphisms are associated with the reported higher capacity of Mp for modulating the host's immune response.


Assuntos
Proteínas de Bactérias/genética , Farmacorresistência Bacteriana Múltipla/genética , Mycobacterium tuberculosis/genética , Polimorfismo de Nucleotídeo Único , Tuberculose Resistente a Múltiplos Medicamentos/microbiologia , Antituberculosos/uso terapêutico , Regulação Bacteriana da Expressão Gênica , Genoma Bacteriano , Genótipo , Interações Hospedeiro-Patógeno , Humanos , Mutação , Mycobacterium tuberculosis/efeitos dos fármacos , Mycobacterium tuberculosis/imunologia , Mycobacterium tuberculosis/patogenicidade , Fenótipo , Regiões Promotoras Genéticas , Tuberculose Resistente a Múltiplos Medicamentos/diagnóstico , Tuberculose Resistente a Múltiplos Medicamentos/tratamento farmacológico , Tuberculose Resistente a Múltiplos Medicamentos/imunologia
11.
Immunology ; 151(1): 122-135, 2017 05.
Artigo em Inglês | MEDLINE | ID: mdl-28106253

RESUMO

Beside its key diagnostic value, the humoral immune response is thought to play a protective role in hantavirus pulmonary syndrome. However, little is known about the cell source of these antibodies during ongoing human infection. Herein we characterized B-cell subsets circulating in Andes-virus-infected patients. A notable potent plasmablast (PB) response that increased 100-fold over the baseline levels was observed around 1 week after the onset of symptoms. These PB present a CD3neg CD19low CD20neg CD38hi CD27hi CD138+/- IgA+/- surface phenotype together with the presence of cytoplasmic functional immunoglobulins. They are large lymphocytes (lymphoblasts) morphologically coincident with the 'immunoblast-like' cells that have been previously described during blood cytology examinations of hantavirus-infected patients. Immunoreactivity analysis of white blood cell lysates suggests that some circulating PB are virus-specific but we also observed a significant increase of reactivity against virus-unrelated antigens, which suggests a possible bystander effect by polyclonal B-cell activation. The presence of this large and transient PB response raises the question as to whether these cells might have a protective or pathological role during the ongoing hantavirus pulmonary syndrome and suggest their practical application as a diagnostic/prognostic biomarker.


Assuntos
Subpopulações de Linfócitos B/imunologia , Síndrome Pulmonar por Hantavirus/imunologia , Orthohantavírus/imunologia , Plasmócitos/imunologia , Células Precursoras de Linfócitos B/imunologia , Doença Aguda , Adulto , Anticorpos Antivirais/sangue , Antígenos CD/metabolismo , Autoantígenos/imunologia , Subpopulações de Linfócitos B/virologia , Biomarcadores/metabolismo , Proliferação de Células , Feminino , Síndrome Pulmonar por Hantavirus/diagnóstico , Humanos , Imunoglobulina A/metabolismo , Ativação Linfocitária , Masculino , Pessoa de Meia-Idade , Plasmócitos/virologia , Células Precursoras de Linfócitos B/virologia , Adulto Jovem
12.
Cell Res ; 25(12): 1333-51, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26482950

RESUMO

The human CD14(+) monocyte compartment is composed by two subsets based on CD16 expression. We previously reported that this compartment is perturbed in tuberculosis (TB) patients, as reflected by the expansion of CD16(+) monocytes along with disease severity. Whether this unbalance is beneficial or detrimental to host defense remains to be elucidated. Here in the context of active TB, we demonstrate that human monocytes are predisposed to differentiate towards an anti-inflammatory (M2-like) macrophage activation program characterized by the CD16(+)CD163(+)MerTK(+)pSTAT3(+) phenotype and functional properties such as enhanced protease-dependent motility, pathogen permissivity and immunomodulation. This process is dependent on STAT3 activation, and loss-of-function experiments point towards a detrimental role in host defense against TB. Importantly, we provide a critical correlation between the abundance of the CD16(+)CD163(+)MerTK(+)pSTAT3(+) cells and the progression of the disease either at the local level in a non-human primate tuberculous granuloma context, or at the systemic level through the detection of the soluble form of CD163 in human sera. Collectively, this study argues for the pathogenic role of the CD16(+)CD163(+)MerTK(+)pSTAT3(+) monocyte-to-macrophage differentiation program and its potential as a target for TB therapy, and promotes the detection of circulating CD163 as a potential biomarker for disease progression and monitoring of treatment efficacy.


Assuntos
Imunomodulação , Interleucina-10/metabolismo , Monócitos/imunologia , Monócitos/patologia , Receptores de IgG/metabolismo , Fator de Transcrição STAT3/metabolismo , Tuberculose/imunologia , Tuberculose/patologia , Humanos
13.
PLoS One ; 9(5): e97837, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24836916

RESUMO

In human tuberculosis (TB), CD8+ T cells contribute to host defense by the release of Th1 cytokines and the direct killing of Mycobacterium tuberculosis (Mtb)-infected macrophages via granule exocytosis pathway or the engagement of receptors on target cells. Previously we demonstrated that strain M, the most prevalent multidrug-resistant (MDR) Mtb strain in Argentine, is a weak inducer of IFN-γ and elicits a remarkably low CD8-dependent cytotoxic T cell activity (CTL). In contrast, the closely related strain 410, which caused a unique case of MDR-TB, elicits a CTL response similar to H37Rv. In this work we extend our previous study investigating some parameters that can account for this discrepancy. We evaluated the expressions of the lytic molecules perforin, granzyme B and granulysin and the chemokine CCL5 in CD8+ T cells as well as activation markers CD69 and CD25 and IL-2 expression in CD4+ and CD8+ T cells stimulated with strains H37Rv, M and 410. Our results demonstrate that M-stimulated CD8+ T cells from purified protein derivative positive healthy donors show low intracellular expression of perforin, granzyme B, granulysin and CCL5 together with an impaired ability to form conjugates with autologous M-pulsed macrophages. Besides, M induces low CD69 and IL-2 expression in CD4+ and CD8+ T cells, being CD69 and IL-2 expression closely associated. Furthermore, IL-2 addition enhanced perforin and granulysin expression as well as the degranulation marker CD107 in M-stimulated CD8+ T cells, making no differences with cells stimulated with strains H37Rv or 410. Thus, our results highlight the role of IL-2 in M-induced CTL activity that drives the proper activation of CD8+ T cells as well as CD4+ T cells collaboration.


Assuntos
Citotoxicidade Imunológica , Farmacorresistência Bacteriana Múltipla , Ativação Linfocitária , Mycobacterium tuberculosis/imunologia , Linfócitos T Citotóxicos/imunologia , Adulto , Antígenos CD/genética , Antígenos CD/metabolismo , Antígenos de Diferenciação de Linfócitos T/genética , Antígenos de Diferenciação de Linfócitos T/metabolismo , Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD4-Positivos/metabolismo , Células Cultivadas , Quimiocina CCL5/genética , Quimiocina CCL5/metabolismo , Feminino , Granzimas/genética , Granzimas/metabolismo , Humanos , Interleucina-2/genética , Interleucina-2/metabolismo , Subunidade alfa de Receptor de Interleucina-2/genética , Subunidade alfa de Receptor de Interleucina-2/metabolismo , Lectinas Tipo C/genética , Lectinas Tipo C/metabolismo , Masculino , Mycobacterium tuberculosis/efeitos dos fármacos , Mycobacterium tuberculosis/genética , Perforina/genética , Perforina/metabolismo , Linfócitos T Citotóxicos/metabolismo
14.
Infect Genet Evol ; 16: 151-6, 2013 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23352891

RESUMO

Mycobacterium tuberculosis has a considerable degree of genetic variability resulting in different epidemiology and disease outcomes. We evaluated the pathogen-host cell interaction of two genetically closely-related multidrug-resistant M. tuberculosis strains of the Haarlem family, namely the strain M, responsible for an extensive multidrug-resistant tuberculosis outbreak, and its kin strain 410 which caused a single case in two decades. Intracellular growth and cytokine responses were evaluated in human monocyte-derived macrophages and dU937 macrophage-like cells. In monocyte-derived macrophages, strain M grew more slowly and induced lower levels of TNF-α and IL-10 than 410, contrasting with previous studies with other strains, where a direct correlation was observed between increased intracellular growth and epidemiological success. On the other hand, in dU937 cells, no difference in growth was observed between both strains, and strain M induced significantly higher TNF-α levels than strain 410. We found that both cell models differed critically in the expression of receptors for M. tuberculosis entry, which might explain the different infection outcomes. Our results in monocyte-derived macrophages suggest that strain M relies on a modest replication rate and cytokine induction, keeping a state of quiescence and remaining rather unnoticed by the host. Collectively, our results underscore the impact of M. tuberculosis intra-species variations on the outcome of host cell infection and show that results can differ depending on the in vitro infection model.


Assuntos
Macrófagos/microbiologia , Mycobacterium tuberculosis/genética , Tuberculose Resistente a Múltiplos Medicamentos/microbiologia , Análise de Variância , Linhagem Celular Tumoral , Proliferação de Células , Células Cultivadas , Citocinas/metabolismo , Feminino , Interações Hospedeiro-Patógeno , Humanos , Macrófagos/citologia , Macrófagos/metabolismo , Masculino , Modelos Biológicos , Mycobacterium tuberculosis/patogenicidade
15.
Buenos Aires; s.n; 1996. 4 p. tab.
Não convencional em Espanhol | LILACS, Sec. Est. Saúde SP, HANSEN, Hanseníase, SESSP-ILSLACERVO, Sec. Est. Saúde SP | ID: biblio-1236974
16.
Medicina (B.Aires) ; 56(6): 705-8, 1996. tab
Artigo em Espanhol | LILACS | ID: lil-196910

RESUMO

El objetivo de este estudio fue evaluar la producción de citoquinas por células mononucleares periféricas (CMP) obtenidas de pacientes con lepra, cuando estas células son estimuladas con ConA, PPD o Myconacterium leprae. Medimos IL-2, IL-4, IFN- y e IL-6 en sobrenadantes libres de células, por enzimoinmunoensayos. Nuestros resultados no sugieren una clara associación entre una forma clínica de lepra y un perfil de secreción de citoquinas de tipo Th1 o Th2 en las CMP de los pacientes con lepra.


Assuntos
Humanos , Masculino , Feminino , Adolescente , Adulto , Pessoa de Meia-Idade , Citocinas/biossíntese , Hanseníase/metabolismo , Células Sanguíneas/metabolismo , Ensaio de Imunoadsorção Enzimática , Hanseníase/imunologia , Macrófagos/metabolismo , Mycobacterium leprae
17.
Arch. argent. dermatol ; 42(2): 73-9, mar.-abr. 1992. ilus
Artigo em Espanhol | LILACS | ID: lil-122886

RESUMO

Se presenta un paciente de 62 años de sexo masculino, con clínica e histología de lepra lepromatosa "burnt out" o "quemada". La piel se observa atrófica y con cicatrices. Se le realizó un estudio inmunológico que determinó un alto nivel de IgG1 (65%) en lugar de los altos niveles de IgG2 habituales en la lepra lepromatosa. La inmunidad humoral reveló valores próximos al polo tuberculoide, vale decir, una gran actividad citotóxica T al enfrentarse con macrófagos autólogos. Se hace referencia a un "Factor N" hereditario que podría mediar en la resistencia ante la lepra y la concurrencia de "factores asociados" en el desarrollo de lepra tuberculoide o lepromatosa


Assuntos
Humanos , Masculino , Pessoa de Meia-Idade , Hanseníase Virchowiana/imunologia , Hanseníase Tuberculoide/imunologia , Eritema Nodoso/tratamento farmacológico , Imunoglobulina G/imunologia , Hanseníase Virchowiana/tratamento farmacológico , Hanseníase Virchowiana/patologia , Hanseníase Tuberculoide/genética
18.
Medicina (B.Aires) ; 50(3): 205-12, 1990. tab
Artigo em Inglês | LILACS | ID: lil-95102

RESUMO

Se valoró la función supresora inducida por Concanavalina A (Con A) en 48 pacientes con hemofilia severa. Cuando se adicionaron cantidades variavles de células inducidas por Con A a un número constante de células T autólogas estimuladas por PHA, se pudieron diferenciar dos grupos de pacientes: en el grupo A (60%) así como en los controles normales, los valores de supresión obtenidos fueron superiores al agregar mayor número de células inducidas por Con A; en el grupo B el agregado en cantidades crecientes de células inducidas por Con A no produjo supresión de la proliferación de células T estimuladas con PHA. El efecto observado en el grupo B pudo ser corregido con inhibidores del metabolismo exidativo del ácido araquidónico presentes durante la etapa de inducción. Los perfiles de supresión definidos no guardaron correlación con la serología para HIV-1 o HBV. Al valorar la evolución clínica, teniendo en cuenta los síntomas y signos del complejo relacionado al SIDA, ésta tendió a ser mejor en el grupo B de pacientes. Se sugiere que la disminución de la actividad supresora inducida por Con A observada en el grupo B es el resultado de un proceso regulatorio normal que involucra productos del metabolismo oxidativo del ácido araquidónico


Assuntos
Humanos , Concanavalina A/farmacologia , Hemofilia A/imunologia , Ativação Linfocitária/efeitos dos fármacos , Linfócitos T/efeitos dos fármacos , Soropositividade para HIV/imunologia , Linfócitos T/imunologia
19.
Medicina (B.Aires) ; 49(3): 213-5, mayo-jun. 1989.
Artigo em Espanhol | LILACS | ID: lil-86671

RESUMO

Son varios los trabajos que tratan de demostrar que en la formal lepromatosa (LL) de la lepra, existirían mecanismos supresores de la respuesta inmune. Al emplear un método de inducción inespecífico, como el sistema de la Concavalina A (ConA), observamos que los pacientes LL tenían disminuida la función supresora, valorada sobre un sistema de proliferación celular T; dicha función tendía a normalizarse durante el episodio de eritema nudoso lepromatoso (ENL). En este sistema demonstramos además, que las células CD8+ (Leu 2a+) eram capaces de interferir en la generación de supresión. Observamos además, que un alto porcentaje de pacientes LL tenían una supresión espontánea elevada; en este tipo de supresión hallados. Por otra parte, hemos demostrado que en este sistema tendría un papel importante el sistema supresor de los monocitos, a través de la liberación de factores solubles (PGE2). Al evaluar la capacidad que tiene el M. leprae para inducir especificamente supresión in vitro la proliferación célular T, hallamos que en los pacientes LL el M. leprae no inducía supresión. Paralelamente, determinamos en sangre periférica, el número de células que tenían el antígeno Leu8+. Observamos que este antígeno estaba marcadamente disminuido, en la fracción de células T, en los pacientes LL y tendía a normalizarse durante el receptores para IL-2 (Tac) durante la etapa de inducción era similar tanto en los TT com LL. La capacidad de las células para proliferar frente a los mitógenos empleados...


Assuntos
Humanos , Antígenos de Bactérias/imunologia , Concanavalina A/farmacologia , Tolerância Imunológica , Hanseníase Virchowiana/imunologia , Mycobacterium leprae/imunologia , Receptores de Interleucina-2/análise , Linfócitos T Reguladores/fisiologia
20.
Bol. Acad. Nac. Med. B.Aires ; 66(2): 451-7, jul.-dic. 1988. tab
Artigo em Espanhol | LILACS | ID: lil-72116

RESUMO

Se valoró la capacidad del M. leprae para inducir supresión de la proliferación celular T, en las diferentes formas clínicass de la enfermedad de Hansen así como en controles normales (inmunizados con BCG). La función supresora se evaluó con un ensayo de dos etapas, utilizando células mononucleares de sangre periférica (PBMC). En la primera etapa se indujo supresión, incubando durante 5 días PBMC con M. leprae gamma-irradiado (Células supresoras, S) o C, se trataron con Mitomicina C y se enfrentaron con células autólogas que se matuvieron congeladas a -80-C. Como mitogénos para evaluar la supresión, se utilizó fitohemagluinina (PHA) y Concanavalina A (Con A). Los resultados indicam que la capacidad del M. leprae para inducir supresión es baja en los pacientes lepromatosos, no así en las demás formas clínicas y en los controles normales. Recientemente inductoras de supresión, que tienen el fenotipo Leu 8+ en la etapa de inducción. Evaluamos las células Leu 8+ en pacientes leprosos y controles normales. Encontramos que las células Leu 8+ estaban descendidas en los pacientes lepromatosos, solamente en la fracción de células T. Este descenso se halló en ambas subpoblaciones, CD4+ y CD8+. Sugerimos que la falla del M. leprae para inducir supresión de la proliferación T en los pacientes lepromatosos, está relacionada al bajo número de células inductoras de supresión (CD4+, Leu8+) en sangre periférica


Assuntos
Humanos , Hanseníase/imunologia , Linfócitos/fisiologia , Linfócitos T Auxiliares-Indutores/fisiologia
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