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1.
Nat Immunol ; 22(7): 839-850, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-34168371

RESUMO

Granulomas are complex cellular structures composed predominantly of macrophages and lymphocytes that function to contain and kill invading pathogens. Here, we investigated the single-cell phenotypes associated with antimicrobial responses in human leprosy granulomas by applying single-cell and spatial sequencing to leprosy biopsy specimens. We focused on reversal reactions (RRs), a dynamic process whereby some patients with disseminated lepromatous leprosy (L-lep) transition toward self-limiting tuberculoid leprosy (T-lep), mounting effective antimicrobial responses. We identified a set of genes encoding proteins involved in antimicrobial responses that are differentially expressed in RR versus L-lep lesions and regulated by interferon-γ and interleukin-1ß. By integrating the spatial coordinates of the key cell types and antimicrobial gene expression in RR and T-lep lesions, we constructed a map revealing the organized architecture of granulomas depicting compositional and functional layers by which macrophages, T cells, keratinocytes and fibroblasts can each contribute to the antimicrobial response.


Assuntos
Hanseníase Virchowiana/imunologia , Hanseníase Tuberculoide/imunologia , Mycobacterium leprae/imunologia , Pele/imunologia , Adolescente , Adulto , Idoso , Feminino , Fibroblastos/imunologia , Fibroblastos/microbiologia , Fibroblastos/patologia , Perfilação da Expressão Gênica , Interações Hospedeiro-Patógeno , Humanos , Queratinócitos/imunologia , Queratinócitos/microbiologia , Queratinócitos/patologia , Hanseníase Virchowiana/genética , Hanseníase Virchowiana/microbiologia , Hanseníase Virchowiana/patologia , Hanseníase Tuberculoide/genética , Hanseníase Tuberculoide/microbiologia , Hanseníase Tuberculoide/patologia , Macrófagos/imunologia , Macrófagos/microbiologia , Macrófagos/patologia , Masculino , Pessoa de Meia-Idade , Mycobacterium leprae/patogenicidade , RNA-Seq , Análise de Célula Única , Pele/microbiologia , Pele/patologia , Linfócitos T/imunologia , Linfócitos T/microbiologia , Linfócitos T/patologia , Transcriptoma
2.
PLoS Negl Trop Dis ; 15(5): e0009382, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-33939710

RESUMO

The World Health Organization has raised concerns about the increasing number of Hansen disease (HD) relapses worldwide, especially in Brazil, India, and Indonesia that report the highest number of recurrent cases. Relapses are an indicator of MDT effectiveness and can reflect Mycobacterium leprae persistence or re-infection. Relapse is also a potential marker for the development or progression of disability. In this research, we studied a large cohort of persons affected by HD treated with full fixed-dose multibacillary (MB) multidrug therapy (MDT) followed for up to 20 years and observed that relapses are a rare event. We estimated the incidence density of relapse in a cohort of patients classified to receive MB regime (bacillary index (BI) > 0), diagnosed between September 1997 and June 2017, and treated with twelve-dose MB-MDT at a HD reference center in Rio de Janeiro, Brazil. We obtained the data from the data management system of the clinic routine service. We linked the selected cases to the dataset of relapses of the national HD data to confirm possible relapse cases diagnosed elsewhere. We diagnosed ten cases of relapse in a cohort of 713 patients followed-up for a mean of 12.1 years. This resulted in an incidence rate of 1.16 relapse cases per 1000 person-year (95% CI = 0.5915-2.076). The accumulated risk was 0.025 in 20 years. The very low risk observed in this cohort of twelve-dose-treated MB patients reinforces the success of the current MDT scheme.


Assuntos
Hansenostáticos/uso terapêutico , Hanseníase Virchowiana/tratamento farmacológico , Hanseníase Virchowiana/epidemiologia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Brasil/epidemiologia , Criança , Pré-Escolar , Clofazimina/uso terapêutico , Dapsona/uso terapêutico , Quimioterapia Combinada , Feminino , Humanos , Incidência , Masculino , Pessoa de Meia-Idade , Mycobacterium leprae/efeitos dos fármacos , Recidiva , Estudos Retrospectivos , Rifampina/uso terapêutico , Pele/microbiologia , Pele/patologia , Adulto Jovem
3.
J Leukoc Biol ; 110(1): 167-176, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-33040382

RESUMO

The enzyme IDO-1 is involved in the first stage of tryptophan catabolism and has been described in both microbicidal and tolerogenic microenvironments. Previous data from our group have shown that IDO-1 is differentially regulated in the distinctive clinical forms of leprosy. The present study aims to investigate the mechanisms associated with IDO-1 expression and activity in human monocyte-derived dendritic cells (mDCs) after stimulation with irradiated Mycobacterium leprae and its fractions. M. leprae and its fractions induced the expression and activity of IDO-1 in human mDCs. Among the stimuli studied, irradiated M. leprae and its membrane fraction (MLMA) induced the production of proinflammatory cytokines TNF and IL-6 whereas irradiated M. leprae and its cytosol fraction (MLSA) induced an increase in IL-10. We investigated if TLR2 activation was necessary for IDO-1 induction in mDCs. We observed that in cultures treated with a neutralizing anti-TLR2 antibody, there was a decrease in IDO-1 activity and expression induced by M. leprae and MLMA. The same effect was observed when we used a MyD88 inhibitor. Our data demonstrate that coculture of mDCs with autologous lymphocytes induced an increase in regulatory T (Treg) cell frequency in MLSA-stimulated cultures, showing that M. leprae constituents may play opposite roles that may possibly be related to the dubious effect of IDO-1 in the different clinical forms of disease. Our data show that M. leprae and its fractions are able to differentially modulate the activity and functionality of IDO-1 in mDCs by a pathway that involves TLR2, suggesting that this enzyme may play an important role in leprosy immunopathogenesis.


Assuntos
Células Dendríticas/imunologia , Células Dendríticas/metabolismo , Tolerância Imunológica , Indolamina-Pirrol 2,3,-Dioxigenase/metabolismo , Hanseníase/etiologia , Hanseníase/metabolismo , Mycobacterium leprae/imunologia , Receptor 2 Toll-Like/metabolismo , Biomarcadores , Citometria de Fluxo , Humanos , Hanseníase/patologia , Linfócitos/imunologia , Linfócitos/metabolismo , Monócitos/imunologia , Monócitos/metabolismo , Fator de Necrose Tumoral alfa/metabolismo
4.
Sci Rep ; 9(1): 16675, 2019 11 13.
Artigo em Inglês | MEDLINE | ID: mdl-31723144

RESUMO

Household contacts (HHC) of leprosy patients exhibit high-risk of developing leprosy and contact tracing is helpful for early diagnosis. From 2011 to 2018,2,437 HHC were examined in a clinic in Rio de Janeiro, Brazil and 16S qPCR was used for diagnosis and monitoring of contacts. Fifty-four HHCs were clinically diagnosed with leprosy at intake. Another 25 exhibited leprosy-like skin lesions at intake, 8 of which were confirmed as having leprosy (50% of which were qPCR positive) and 17 of which were diagnosed with other skin diseases (6% qPCR positive). In skin biopsies, qPCR presented a sensitivity of 0.50 and specificity of 0.94. Furthermore, 955 healthy HHCs were followed-up for at least 3 years and skin scrapings were collected from earlobes for qPCR detection. Positive qPCR indicated a non-significant relative risk of 2.52 of developing the disease. During follow-up, those who progressed towards leprosy exhibited 20% qPCR positivity, compared to 9% of those who remained healthy. Disease-free survival rates indicated that age had a significant impact on disease progression, where patients over 60 had a greater chance of developing leprosy [HR = 32.4 (3.6-290.3)]. Contact tracing combined with qPCR may assist in early diagnosis and age is a risk factor for leprosy progression.


Assuntos
Busca de Comunicante/métodos , DNA Bacteriano/análise , DNA Ribossômico/análise , Características da Família , Hanseníase/diagnóstico , Mycobacterium leprae/isolamento & purificação , Reação em Cadeia da Polimerase em Tempo Real/métodos , Adolescente , Adulto , Brasil/epidemiologia , Estudos de Casos e Controles , Criança , Pré-Escolar , Estudos de Coortes , Feminino , Seguimentos , Humanos , Lactente , Hanseníase/epidemiologia , Hanseníase/genética , Masculino , Pessoa de Meia-Idade , Técnicas de Diagnóstico Molecular , Mycobacterium leprae/genética , Fatores de Tempo , Adulto Jovem
5.
J Clin Invest ; 129(5): 1926-1939, 2019 04 02.
Artigo em Inglês | MEDLINE | ID: mdl-30939123

RESUMO

IL-26 is an antimicrobial protein secreted by Th17 cells that has the ability to directly kill extracellular bacteria. To ascertain whether IL-26 contributes to host defense against intracellular bacteria, we studied leprosy, caused by the obligate intracellular pathogen Mycobacterium leprae, as a model. Analysis of leprosy skin lesions by gene expression profiling and immunohistology revealed that IL-26 was more strongly expressed in lesions from the self-limited tuberculoid compared with expression in progressive lepromatous patients. IL-26 directly bound to M. leprae in axenic culture and reduced bacteria viability. Furthermore, IL-26, when added to human monocyte-derived macrophages infected with M. leprae, entered the infected cell, colocalized with the bacterium, and reduced bacteria viability. In addition, IL-26 induced autophagy via the cytoplasmic DNA receptor stimulator of IFN genes (STING), as well as fusion of phagosomes containing bacilli with lysosomal compartments. Altogether, our data suggest that the Th17 cytokine IL-26 contributes to host defense against intracellular bacteria.


Assuntos
Interleucinas/imunologia , Hanseníase Virchowiana/microbiologia , Hanseníase Tuberculoide/microbiologia , Células Th17/imunologia , Autofagia , Citocinas/imunologia , Perfilação da Expressão Gênica , Humanos , Lisossomos/imunologia , Lisossomos/microbiologia , Macrófagos/imunologia , Monócitos/citologia , Mycobacterium leprae , Mycobacterium tuberculosis , Fagossomos/imunologia , Proteínas Recombinantes/imunologia , Transdução de Sinais
6.
JCI Insight ; 4(8)2019 04 18.
Artigo em Inglês | MEDLINE | ID: mdl-30996142

RESUMO

DC, through the uptake, processing, and presentation of antigen, are responsible for activation of T cell responses to defend the host against infection, yet it is not known if they can directly kill invading bacteria. Here, we studied in human leprosy, how Langerhans cells (LC), specialized DC, contribute to host defense against bacterial infection. IFN-γ treatment of LC isolated from human epidermis and infected with Mycobacterium leprae (M. leprae) activated an antimicrobial activity, which was dependent on the upregulation of the antimicrobial peptide cathelicidin and induction of autophagy. IFN-γ induction of autophagy promoted fusion of phagosomes containing M. leprae with lysosomes and the delivery of cathelicidin to the intracellular compartment containing the pathogen. Autophagy enhanced the ability of M. leprae-infected LC to present antigen to CD1a-restricted T cells. The frequency of IFN-γ labeling and LC containing both cathelicidin and autophagic vesicles was greater in the self-healing lesions vs. progressive lesions, thus correlating with the effectiveness of host defense against the pathogen. These data indicate that autophagy links the ability of DC to kill and degrade an invading pathogen, ensuring cell survival from the infection while facilitating presentation of microbial antigens to resident T cells.


Assuntos
Apresentação do Antígeno , Autofagia , Células de Langerhans/imunologia , Hanseníase/imunologia , Mycobacterium leprae/imunologia , Antígenos de Bactérias/imunologia , Peptídeos Catiônicos Antimicrobianos/imunologia , Peptídeos Catiônicos Antimicrobianos/metabolismo , Autofagossomos/imunologia , Autofagossomos/metabolismo , Autofagossomos/microbiologia , Biópsia , Células Cultivadas , Epiderme/imunologia , Epiderme/microbiologia , Epiderme/patologia , Humanos , Interferon gama/imunologia , Células de Langerhans/microbiologia , Células de Langerhans/ultraestrutura , Hanseníase/microbiologia , Hanseníase/patologia , Lisossomos/imunologia , Lisossomos/metabolismo , Lisossomos/microbiologia , Microscopia Eletrônica de Transmissão , Mycobacterium leprae/isolamento & purificação , Cultura Primária de Células , Proteínas Recombinantes/imunologia , Linfócitos T/imunologia , Regulação para Cima/imunologia
7.
Am J Trop Med Hyg ; 100(2): 377-385, 2019 02.
Artigo em Inglês | MEDLINE | ID: mdl-30652669

RESUMO

Type 2 reaction (T2R) or erythema nodosum leprosum (ENL), a sudden episode of acute inflammation predominantly affecting lepromatous leprosy patients (LL), characterized by a reduced cellular immune response. This possibly indicates a close relationship between the onset of T2R and the altered frequency, and functional activity of T lymphocytes, particularly of memory subsets. This study performed ex vivo and in vitro characterizations of T cell blood subpopulations from LL patients with or without T2R. In addition, the evaluation of activity of these subpopulations was performed by analyzing the frequency of these cells producing IFN-γ, TNF, and IL-10 by flow cytometry. Furthermore, the expression of transcription factors, for the differentiation of T cells, were analyzed by quantitative real-time polymerase chain reaction. Our results showed an increased frequency of CD8+/TNF+ effector memory T cells (TEM) among T2Rs. Moreover, there was evidence of a reduced frequency of CD4 and CD8+ IFN-γ-producing cells in T2R, and a reduced expression of STAT4 and TBX21. Finally, a significant and positive correlation between bacteriological index (BI) of T2R patients and CD4+/TNF+ and CD4+/IFN-γ+ T cells was observed. Thus, negative correlation between BI and the frequency of CD4+/IL-10+ T cells was noted. These results suggest that CD8+/TNF+ TEM are primarily responsible for the transient alteration in the immune response to Mycobacterium leprae in ENL patients. Thus, our study improves our understanding of pathogenic mechanisms and might suggest new therapeutic approaches for leprosy.


Assuntos
Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD8-Positivos/imunologia , Eritema Nodoso/imunologia , Hanseníase Virchowiana/imunologia , Mycobacterium leprae/patogenicidade , Fator de Necrose Tumoral alfa/imunologia , Adolescente , Adulto , Idoso , Linfócitos T CD4-Positivos/microbiologia , Linfócitos T CD8-Positivos/microbiologia , Estudos de Casos e Controles , Eritema Nodoso/genética , Eritema Nodoso/patologia , Feminino , Regulação da Expressão Gênica , Interações Hospedeiro-Patógeno/genética , Interações Hospedeiro-Patógeno/imunologia , Humanos , Memória Imunológica , Imunofenotipagem , Interferon gama/genética , Interferon gama/imunologia , Interleucina-10/genética , Interleucina-10/imunologia , Hanseníase Virchowiana/genética , Hanseníase Virchowiana/patologia , Masculino , Pessoa de Meia-Idade , Mycobacterium leprae/crescimento & desenvolvimento , Mycobacterium leprae/imunologia , Cultura Primária de Células , Fator de Transcrição STAT4/genética , Fator de Transcrição STAT4/imunologia , Transdução de Sinais , Proteínas com Domínio T/genética , Proteínas com Domínio T/imunologia , Fator de Necrose Tumoral alfa/genética
9.
JCI Insight ; 1(15): e88843, 2016 09 22.
Artigo em Inglês | MEDLINE | ID: mdl-27699251

RESUMO

Transcriptome profiles derived from the site of human disease have led to the identification of genes that contribute to pathogenesis, yet the complex mixture of cell types in these lesions has been an obstacle for defining specific mechanisms. Leprosy provides an outstanding model to study host defense and pathogenesis in a human infectious disease, given its clinical spectrum, which interrelates with the host immunologic and pathologic responses. Here, we investigated gene expression profiles derived from skin lesions for each clinical subtype of leprosy, analyzing gene coexpression modules by cell-type deconvolution. In lesions from tuberculoid leprosy patients, those with the self-limited form of the disease, dendritic cells were linked with MMP12 as part of a tissue remodeling network that contributes to granuloma formation. In lesions from lepromatous leprosy patients, those with disseminated disease, macrophages were linked with a gene network that programs phagocytosis. In erythema nodosum leprosum, neutrophil and endothelial cell gene networks were identified as part of the vasculitis that results in tissue injury. The present integrated computational approach provides a systems approach toward identifying cell-defined functional networks that contribute to host defense and immunopathology at the site of human infectious disease.


Assuntos
Redes Reguladoras de Genes , Hanseníase/genética , Hanseníase/imunologia , Adolescente , Adulto , Eritema Nodoso/genética , Eritema Nodoso/imunologia , Feminino , Humanos , Hanseníase Virchowiana/genética , Hanseníase Virchowiana/imunologia , Hanseníase Tuberculoide/genética , Hanseníase Tuberculoide/imunologia , Masculino , Pessoa de Meia-Idade , Transcriptoma , Adulto Jovem
10.
J Immunol ; 197(5): 1905-13, 2016 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-27474073

RESUMO

The chronic course of lepromatous leprosy may be interrupted by acute inflammatory episodes known as erythema nodosum leprosum (ENL). Despite its being a major cause of peripheral nerve damage in leprosy patients, the immunopathogenesis of ENL remains ill-defined. Recognized by distinct families of germline-encoded pattern recognition receptors, endogenous and pathogen-derived nucleic acids are highly immunostimulatory molecules that play a major role in the host defense against infections, autoimmunity, and autoinflammation. The aim of this work was to investigate whether DNA sensing via TLR-9 constitutes a major inflammatory pathway during ENL. Flow cytometry and immunohistochemistry analysis showed significantly higher TLR-9 expression in ENL when compared with nonreactional lepromatous patients, both locally in the skin lesions and in circulating mononuclear cells. The levels of endogenous and pathogen-derived TLR-9 ligands in the circulation of ENL patients were also higher. Furthermore, PBMCs isolated from the ENL patients secreted higher levels of TNF, IL-6, and IL-1ß in response to a TLR-9 agonist than those of the nonreactional patients and healthy individuals. Finally, E6446, a TLR-9 synthetic antagonist, was able to significantly inhibit the secretion of proinflammatory cytokines by ENL PBMCs in response to Mycobacterium leprae lysate. Our data strongly indicate that DNA sensing via TLR-9 constitutes a major innate immunity pathway involved in the pathogenesis and evolution of ENL. Thus, the use of TLR-9 antagonists emerges as a potential alternative to more effectively treat ENL aiming to prevent the development of nerve injuries and deformities in leprosy.


Assuntos
DNA/metabolismo , Eritema Nodoso/imunologia , Imunidade Inata , Hanseníase Virchowiana/imunologia , Transdução de Sinais , Receptor Toll-Like 9/metabolismo , Adulto , Idoso , Idoso de 80 Anos ou mais , Eritema Nodoso/microbiologia , Feminino , Citometria de Fluxo , Humanos , Hanseníase Virchowiana/microbiologia , Leucócitos Mononucleares/imunologia , Leucócitos Mononucleares/microbiologia , Masculino , Pessoa de Meia-Idade , Mycobacterium leprae/química , Mycobacterium leprae/imunologia , Receptor Toll-Like 9/imunologia , Adulto Jovem
11.
PLoS Pathog ; 12(6): e1005705, 2016 06.
Artigo em Inglês | MEDLINE | ID: mdl-27355424

RESUMO

Triggering antimicrobial mechanisms in macrophages infected with intracellular pathogens, such as mycobacteria, is critical to host defense against the infection. To uncover the unique and shared antimicrobial networks induced by the innate and adaptive immune systems, gene expression profiles generated by RNA sequencing (RNAseq) from human monocyte-derived macrophages (MDMs) activated with TLR2/1 ligand (TLR2/1L) or IFN-γ were analyzed. Weighed gene correlation network analysis identified modules of genes strongly correlated with TLR2/1L or IFN-γ that were linked by the "defense response" gene ontology term. The common TLR2/1L and IFN-γ inducible human macrophage host defense network contained 16 antimicrobial response genes, including S100A12, which was one of the most highly induced genes by TLR2/1L. There is limited information on the role of S100A12 in infectious disease, leading us to test the hypothesis that S100A12 contributes to host defense against mycobacterial infection in humans. We show that S100A12 is sufficient to directly kill Mycobacterium tuberculosis and Mycobacterium leprae. We also demonstrate that S100A12 is required for TLR2/1L and IFN-γ induced antimicrobial activity against M. leprae in infected macrophages. At the site of disease in leprosy, we found that S100A12 was more strongly expressed in skin lesions from tuberculoid leprosy (T-lep), the self-limiting form of the disease, compared to lepromatous leprosy (L-lep), the progressive form of the disease. These data suggest that S100A12 is part of an innate and adaptive inducible antimicrobial network that contributes to host defense against mycobacteria in infected macrophages.


Assuntos
Hanseníase/imunologia , Macrófagos/imunologia , Proteína S100A12/imunologia , Citometria de Fluxo , Imunofluorescência , Perfilação da Expressão Gênica , Humanos , Macrófagos/microbiologia , Infecções por Mycobacterium/imunologia , Mycobacterium leprae/imunologia , Mycobacterium tuberculosis/imunologia , Reação em Cadeia da Polimerase em Tempo Real , Transcriptoma
12.
J Mass Spectrom ; 50(12): 1374-85, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26634971

RESUMO

Leprosy still represents a health problem in several countries. Affecting skin and peripheral nerves, it may lead to permanent disabilities. Disturbances on skin lipid metabolism in leprosy were already observed; however, the localization and distribution of lipids could not be accessed. The role of lipids on infectious disease has been fully addressed only recently, as they directly influence immune response. Matrix-assisted laser desorption/ionization imaging mass spectrometry provides a powerful tool to localize and identify lipids in tissues. The aim of this work was to study and compare the changes in lipid distribution of skin biopsies taken from leprosy patients before and after multidrug therapy (MDT). Different species of phosphatidic acid, phosphatidylethanolamine, phosphatidylserine, phosphatidylinositol, sphingomyelin and phosphatidylcholine were detected. Differences in skin lipid signal intensities, as well as in their localization, were observed before and after MDT in every patient. In general, lipid distribution in the skin after MDT had a pattern similar to control skin samples, where most of the lipids were located in the upper part of the dermis and epidermis. This study opens paths to a better understanding of lipid functions in leprosy pathogenesis and immune response.

13.
J Transl Med ; 13: 296, 2015 Sep 11.
Artigo em Inglês | MEDLINE | ID: mdl-26362198

RESUMO

BACKGROUND: Peripheral nerve injury and bone lesions, well known leprosy complications, lead to deformities and incapacities. The phosphate-regulating gene with homologies to endopeptidase on the X chromosome (PHEX) encodes a homonymous protein (PHEX) implicated in bone metabolism. PHEX/PHEX alterations may result in bone and cartilage lesions. PHEX expression is downregulated by intracellular Mycobacterium leprae (M. leprae) in cultures of human Schwann cells and osteoblasts. M. leprae in vivo effect on PHEX/PHEX is not known. METHODS: Cross-sectional observational study of 36 leprosy patients (22 lepromatous and 14 borderline-tuberculoid) and 20 healthy volunteers (HV). The following tests were performed: PHEX flow cytometric analysis on blood mononuclear cells, cytokine production in culture supernatant, 25-hydroxyvitamin D (OHvitD) serum levels and (99m)Tc-MDP three-phase bone scintigraphy, radiography of upper and lower extremities and blood and urine biochemistry. RESULTS: Significantly lower PHEX expression levels were observed in lepromatous patients than in the other groups (χ(2) = 16.554, p < 0.001 for lymphocytes and χ(2) = 13.933, p = 0.001 for monocytes). Low levels of 25-(OHvitD) were observed in HV (median = 23.0 ng/mL) and BT patients (median = 27.5 ng/mL) and normal serum levels were found in LL patients (median = 38.6 ng/mL). Inflammatory cytokines, such as TNF, a PHEX transcription repressor, were lower after stimulation with M. leprae in peripheral blood mononuclear cells from lepromatous in comparison to BT patients and HV (χ(2) = 10.820, p < 0.001). CONCLUSION: Downregulation of PHEX may constitute an important early component of bone loss and joint damage in leprosy. The present results suggest a direct effect produced by M. leprae on the osteoarticular system that may use this mechanism.


Assuntos
Regulação para Baixo , Hanseníase Dimorfa/metabolismo , Hanseníase Multibacilar/metabolismo , Endopeptidase Neutra Reguladora de Fosfato PHEX/metabolismo , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Osso e Ossos/microbiologia , Cartilagem/microbiologia , Estudos Transversais , Citocinas/metabolismo , Feminino , Citometria de Fluxo , Voluntários Saudáveis , Humanos , Inflamação/metabolismo , Inflamação/microbiologia , Leucócitos Mononucleares/metabolismo , Masculino , Pessoa de Meia-Idade , Osteoblastos/microbiologia , Células de Schwann/microbiologia , Medronato de Tecnécio Tc 99m , Adulto Jovem
14.
J Invest Dermatol ; 135(10): 2410-2417, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26030183

RESUMO

The mechanisms by which intracellular pathogens trigger immunosuppressive pathways are critical for understanding the pathogenesis of microbial infection. One pathway that inhibits host defense responses involves the induction of type I interferons and subsequently IL-10, yet the mechanism by which type I IFN induces IL-10 remains unclear. Our studies of gene expression profiles derived from leprosy skin lesions suggested a link between IL-27 and the IFN-ß induced IL-10 pathway. Here, we demonstrate that the IL-27p28 subunit is upregulated following treatment of monocytes with IFN-ß and Mycobacterium leprae, the intracellular bacterium that causes leprosy. The ability of IFN-ß and M. leprae to induce IL-10 was diminished by IL-27 knockdown. Additionally, treatment of monocytes with recombinant IL-27 was sufficient to induce the production of IL-10. Functionally, IL-27 inhibited the ability of IFN-γ to trigger antimicrobial activity against M. leprae in infected monocytes. At the site of disease, IL-27 was more strongly expressed in skin lesions of patients with progressive lepromatous leprosy, correlating and colocalizing with IFN-ß and IL-10 in macrophages. Together, these data provide evidence that in the human cutaneous immune responses to microbial infection, IL-27 contributes to the suppression of host antimicrobial responses.


Assuntos
Interferon beta/farmacologia , Interleucina-10/metabolismo , Interleucina-27/metabolismo , Hanseníase Virchowiana/tratamento farmacológico , Hanseníase Virchowiana/metabolismo , Mycobacterium leprae/metabolismo , Animais , Biomarcadores/metabolismo , Células Cultivadas , Citocinas/metabolismo , Ensaio de Imunoadsorção Enzimática , Humanos , Imunossupressores/farmacologia , Interleucina-27/farmacologia , Hanseníase Virchowiana/patologia , Camundongos , Microscopia Confocal , Modelos Animais , Monócitos/citologia , Monócitos/efeitos dos fármacos , Mycobacterium leprae/patogenicidade , Prognóstico , RNA Interferente Pequeno/metabolismo , Reação em Cadeia da Polimerase em Tempo Real/métodos , Amostragem , Sensibilidade e Especificidade , Transfecção
15.
Appl Immunohistochem Mol Morphol ; 23(3): 220-9, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25221954

RESUMO

Nerve damage in leprosy can be directly induced by Mycobacterium leprae in the early stages of infection, however, immunomediated mechanisms add gravity to the impairment of neural function in symptomatic periods of the disease. This study investigated the immunohistochemical expression of immunomarkers involved in the pathogenic mechanisms of leprosy nerve damage. These markers selected were CXCL10, CCL2 chemokines and immunomarkers as CD3, CD4, CD8, CD45RA, CD45RO, CD68, HLA-DR, and metalloproteinases 2 and 9 (MMP2 and MMP9) occurring in nerve biopsy specimens collected from leprosy (23) and nonleprosy patients (5) suffering peripheral neuropathy. CXCL10, CCL2, MMP2, and MMP9 immunoreactivities were found in the leprosy nerves but not in nonleprosy samples. Immunolabeling was predominantly found in recruited macrophages and Schwann cells composing the inflammatory cellular population in the leprosy-affected nerves. The immunohistochemical expression of all the markers, but CXCL10, was associated with fibrosis, however, only CCL2 was, independently from the others, associated with this excessive deposit of extracellular matrix. No difference in the frequency of the immunolabeling was detected between the AFB⁺ and AFB⁻ leprosy subgroups of nerve, exception made to some statistical trend to difference in regard to CD68⁻ and HLA-DR⁺ cells in the AFB⁻ nerves exhibiting epithelioid granuloma. MMP9 expression associated with fibrosis is consistent with previous results of research group. The findings conveys the idea that CCL2 and CXCL10 chemokines at least in advanced stages of leprosy nerve lesions are not determinant for the establishment of AFB⁺ or AFB⁻ leprosy lesions, however, CCL2 is associated with macrophage recruitment and fibrosis.


Assuntos
Quimiocina CCL2/metabolismo , Quimiocina CXCL10/metabolismo , Hanseníase Tuberculoide/mortalidade , Nervos Periféricos/metabolismo , Nervos Periféricos/patologia , Adolescente , Adulto , Idoso , Biomarcadores/metabolismo , Feminino , Humanos , Hanseníase Tuberculoide/patologia , Masculino , Pessoa de Meia-Idade
16.
PLoS Negl Trop Dis ; 8(9): e3099, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-25187983

RESUMO

Mycobacterium leprae infects macrophages and Schwann cells inducing a gene expression program to facilitate its replication and progression to disease. MicroRNAs (miRNAs) are key regulators of gene expression and could be involved during the infection. To address the genetic influence of miRNAs in leprosy, we enrolled 1,098 individuals and conducted a case-control analysis in order to study four miRNAs genes containing single nucleotide polymorphism (miRSNP). We tested miRSNP-125a (rs12975333 G>T), miRSNP-223 (rs34952329 *>T), miRSNP-196a-2 (rs11614913 C>T) and miRSNP-146a (rs2910164 G>C). Amongst them, miRSNP-146a was the unique gene associated with risk to leprosy per se (GC OR = 1.44, p = 0.04; CC OR = 2.18, p = 0.0091). We replicated this finding showing that the C-allele was over-transmitted (p = 0.003) using a transmission-disequilibrium test. A functional analysis revealed that live M. leprae (MOI 100:1) was able to induce miR-146a expression in THP-1 (p<0.05). Furthermore, pure neural leprosy biopsies expressed augmented levels of that miRNA as compared to biopsy samples from neuropathies not related with leprosy (p = 0.001). Interestingly, carriers of the risk variant (C-allele) produce higher levels of mature miR-146a in nerves (p = 0.04). From skin biopsies, although we observed augmented levels of miR-146a, we were not able to correlate it with a particular clinical form or neither host genotype. MiR-146a is known to modulate TNF levels, thus we assessed TNF expression (nerve biopsies) and released by peripheral blood mononuclear cells infected with BCG Moreau. In both cases lower TNF levels correlates with subjects carrying the risk C-allele, (p = 0.0453 and p = 0.0352; respectively), which is consistent with an immunomodulatory role of this miRNA in leprosy.


Assuntos
Alelos , Predisposição Genética para Doença , Hanseníase/genética , Leucócitos Mononucleares/metabolismo , MicroRNAs/metabolismo , Polimorfismo de Nucleotídeo Único , Estudos de Casos e Controles , Genótipo , Heterozigoto , Humanos , MicroRNAs/genética
17.
Cell Microbiol ; 16(6): 797-815, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24552180

RESUMO

We recently showed that Mycobacterium leprae (ML) is able to induce lipid droplet formation in infected macrophages. We herein confirm that cholesterol (Cho) is one of the host lipid molecules that accumulate in ML-infected macrophages and investigate the effects of ML on cellular Cho metabolism responsible for its accumulation. The expression levels of LDL receptors (LDL-R, CD36, SRA-1, SR-B1, and LRP-1) and enzymes involved in Cho biosynthesis were investigated by qRT-PCR and/or Western blot and shown to be higher in lepromatous leprosy (LL) tissues when compared to borderline tuberculoid (BT) lesions. Moreover, higher levels of the active form of the sterol regulatory element-binding protein (SREBP) transcriptional factors, key regulators of the biosynthesis and uptake of cellular Cho, were found in LL skin biopsies. Functional in vitro assays confirmed the higher capacity of ML-infected macrophages to synthesize Cho and sequester exogenous LDL-Cho. Notably, Cho colocalized to ML-containing phagosomes, and Cho metabolism impairment, through either de novo synthesis inhibition by statins or depletion of exogenous Cho, decreased intracellular bacterial survival. These findings highlight the importance of metabolic integration between the host and bacteria to leprosy pathophysiology, opening new avenues for novel therapeutic strategies to leprosy.


Assuntos
Colesterol/metabolismo , Interações Hospedeiro-Patógeno , Macrófagos/microbiologia , Viabilidade Microbiana , Mycobacterium leprae/fisiologia , Fagossomos/microbiologia , Animais , Western Blotting , Células Cultivadas , Perfilação da Expressão Gênica , Humanos , Hanseníase/tratamento farmacológico , Macrófagos/metabolismo , Camundongos Endogâmicos C57BL , Fagossomos/metabolismo , Reação em Cadeia da Polimerase em Tempo Real , Receptores de LDL/biossíntese , Receptores de LDL/genética , Proteínas de Ligação a Elemento Regulador de Esterol/biossíntese , Proteínas de Ligação a Elemento Regulador de Esterol/genética
18.
Trans R Soc Trop Med Hyg ; 108(2): 63-70, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24361943

RESUMO

BACKGROUND: Many articles have shown that HIV infection can modify the clinical course of leprosy, but very scant epidemiological and clinical data about this co-infection are available in the peer-reviewed literature. METHODS: We herein describe the geographical distribution and demographic characteristics of 92 HIV/Mycobacterium leprae co-infected patients assisted in a Brazilian Leprosy referral center. A multivariate analysis was performed in order to establish clinical factors associated with type 1 reaction. RESULTS: Co-infected patient admissions have steadily increased over the last years at this referral center. Most patients were men, with a mean age of 32.3 years and presenting with the paucibacillary form of leprosy. The use of antiretroviral therapy (ART) was the only factor associated with type 1 reaction. Most patients were living in the metropolitan area and the north sub area of Rio de Janeiro City. CONCLUSION: Co-infected patients receiving ART have a greater chance to develop type 1 reaction. Patients living with both HIV and leprosy are likely to live in regions characterized by a high density impoverished population.


Assuntos
Infecções por HIV/epidemiologia , Hanseníase/epidemiologia , Adolescente , Adulto , Fatores Etários , Idoso , Brasil/epidemiologia , Coinfecção/epidemiologia , Coinfecção/microbiologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Mycobacterium leprae , Distribuição por Sexo , Adulto Jovem
19.
s.l; s.n; 2014. 8 p. tab, graf.
Não convencional em Inglês | SES-SP, HANSEN, SESSP-ILSLPROD, SES-SP, SESSP-ILSLACERVO, SES-SP | ID: biblio-1095368

RESUMO

Mycobacterium leprae infects macrophages and Schwann cells inducing a gene expression program to facilitate its replication and progression to disease. MicroRNAs (miRNAs) are key regulators of gene expression and could be involved during the infection. To address the genetic influence of miRNAs in leprosy, we enrolled 1,098 individuals and conducted a case-control analysis in order to study four miRNAs genes containing single nucleotide polymorphism (miRSNP). We tested miRSNP-125a (rs12975333 G>T), miRSNP-223 (rs34952329 *>T), miRSNP-196a-2 (rs11614913 C>T) and miRSNP-146a (rs2910164 G>C). Amongst them, miRSNP-146a was the unique gene associated with risk to leprosy per se (GC OR = 1.44, p = 0.04; CC OR = 2.18, p = 0.0091). We replicated this finding showing that the C-allele was over-transmitted (p = 0.003) using a transmission-disequilibrium test. A functional analysis revealed that live M. leprae (MOI 100:1) was able to induce miR-146a expression in THP-1 (p<0.05). Furthermore, pure neural leprosy biopsies expressed augmented levels of that miRNA as compared to biopsy samples from neuropathies not related with leprosy (p = 0.001). Interestingly, carriers of the risk variant (C-allele) produce higher levels of mature miR-146a in nerves (p = 0.04). From skin biopsies, although we observed augmented levels of miR-146a, we were not able to correlate it with a particular clinical form or neither host genotype. MiR-146a is known to modulate TNF levels, thus we assessed TNF expression (nerve biopsies) and released by peripheral blood mononuclear cells infected with BCG Moreau. In both cases lower TNF levels correlates with subjects carrying the risk C-allele, (p = 0.0453 and p = 0.0352; respectively), which is consistent with an immunomodulatory role of this miRNA in leprosy.


Assuntos
Humanos , Leucócitos Mononucleares/metabolismo , Estudos de Casos e Controles , Predisposição Genética para Doença , Polimorfismo de Nucleotídeo Único , MicroRNAs/genética , MicroRNAs/metabolismo , Alelos , Genótipo , Heterozigoto , Hanseníase/genética
20.
PLoS Negl Trop Dis ; 7(8): e2381, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23967366

RESUMO

Despite considerable efforts over the last decades, our understanding of leprosy pathogenesis remains limited. The complex interplay between pathogens and hosts has profound effects on host metabolism. To explore the metabolic perturbations associated with leprosy, we analyzed the serum metabolome of leprosy patients. Samples collected from lepromatous and tuberculoid patients before and immediately after the conclusion of multidrug therapy (MDT) were subjected to high-throughput metabolic profiling. Our results show marked metabolic alterations during leprosy that subside at the conclusion of MDT. Pathways showing the highest modulation were related to polyunsaturated fatty acid (PUFA) metabolism, with emphasis on anti-inflammatory, pro-resolving omega-3 fatty acids. These results were confirmed by eicosanoid measurements through enzyme-linked immunoassays. Corroborating the repertoire of metabolites altered in sera, metabonomic analysis of skin specimens revealed alterations in the levels of lipids derived from lipase activity, including PUFAs, suggesting a high lipid turnover in highly-infected lesions. Our data suggest that omega-6 and omega-3, PUFA-derived, pro-resolving lipid mediators contribute to reduced tissue damage irrespectively of pathogen burden during leprosy disease. Our results demonstrate the utility of a comprehensive metabonomic approach for identifying potential contributors to disease pathology that may facilitate the development of more targeted treatments for leprosy and other inflammatory diseases.


Assuntos
Anti-Inflamatórios/metabolismo , Ácidos Graxos Insaturados/metabolismo , Interações Hospedeiro-Parasita , Hanseníase/imunologia , Hanseníase/patologia , Metaboloma , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Criança , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Plasma/química , Pele/química , Pele/patologia , Adulto Jovem
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