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Background: Leprosy is an infectious disease that mostly affects underserved populations. Although it has been largely eliminated, still about 200'000 new patients are diagnosed annually. In the absence of a diagnostic test, clinical diagnosis is often delayed, potentially leading to irreversible neurological damage and its resulting stigma, as well as continued transmission. Accelerating diagnosis could significantly contribute to advancing global leprosy elimination. Digital and Artificial Intelligence (AI) driven technology has shown potential to augment health workers abilities in making faster and more accurate diagnosis, especially when using images such as in the fields of dermatology or ophthalmology. That made us start the quest for an AI-driven diagnosis assistant for leprosy, based on skin images. Methods: Here we describe the accuracy of an AI-enabled image-based diagnosis assistant for leprosy, called AI4Leprosy, based on a combination of skin images and clinical data, collected following a standardized process. In a Brazilian leprosy national referral center, 222 patients with leprosy or other dermatological conditions were included, and the 1229 collected skin images and 585 sets of metadata are stored in an open-source dataset for other researchers to exploit. Findings: We used this dataset to test whether a CNN-based AI algorithm could contribute to leprosy diagnosis and employed three AI models, testing images and metadata both independently and in combination. AI modeling indicated that the most important clinical signs are thermal sensitivity loss, nodules and papules, feet paresthesia, number of lesions and gender, but also scaling surface and pruritus that were negatively associated with leprosy. Using elastic-net logistic regression provided a high classification accuracy (90%) and an area under curve (AUC) of 96.46% for leprosy diagnosis. Interpretation: Future validation of these models is underway, gathering larger datasets from populations of different skin types and collecting images with smartphone cameras to mimic real world settings. We hope that the results of our research will lead to clinical solutions that help accelerate global leprosy elimination. Funding: This study was partially funded by Novartis Foundation and Microsoft (in-kind contribution).
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The diagnosis of pure neural leprosy is more challenging because patients share characteristics with other common pathologies, such as ulnar compression, which should be taken into consideration for differential diagnosis. In this study, we identify ulnar nerve conduction characteristics to aid in the differential diagnosis of ulnar neuropathy (UN) in leprosy and that of non-leprosy etiology. In addition, we include putative markers to better understand the inflammatory process that may occur in the nerve. Data were extracted from a database of people affected by leprosy (leprosy group) diagnosed with UN at leprosy diagnosis. A non-leprosy group of patients diagnosed with mechanical neuropathy (compressive, traumatic) was also included. Both groups were submitted to clinical, neurological, neurophysiological and immunological studies. Nerve enlargement and sensory impairment were significantly higher in leprosy patients than in patients with compressive UN. Bilateral impairment was significantly higher in the leprosy group than in the non-leprosy group. Leprosy reactions were associated to focal demyelinating lesions at the elbow and to temporal dispersion (TD). Clinical signs such as sensory impairment, nerve enlargement and bilateral ulnar nerve injury associated with eletrodiagnostic criteria such as demyelinating finds, specifically temporal dispersion, could be tools to help us decided on the best conduct in patients with elbow ulnar neuropathy and specifically decide if we should perform a nerve biopsy for diagnosis of pure neural leprosy.
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Hanseníase/diagnóstico , Hanseníase/metabolismo , Neuropatias Ulnares/diagnóstico , Adolescente , Adulto , Idoso , Biomarcadores , Brasil/epidemiologia , Estudos Transversais , Gerenciamento de Dados , Bases de Dados Factuais , Diagnóstico Diferencial , Articulação do Cotovelo , Feminino , Humanos , Hanseníase Tuberculoide , Masculino , Pessoa de Meia-Idade , Condução Nervosa , Nervo Ulnar/metabolismo , Neuropatias Ulnares/fisiopatologiaRESUMO
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.
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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 JovemRESUMO
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.
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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/metabolismoRESUMO
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.
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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 JovemRESUMO
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.
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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/genéticaRESUMO
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.
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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.
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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 JovemRESUMO
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⺠and AFB⻠leprosy subgroups of nerve, exception made to some statistical trend to difference in regard to CD68⻠and HLA-DR⺠cells in the AFB⻠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⺠or AFB⻠leprosy lesions, however, CCL2 is associated with macrophage recruitment and fibrosis.
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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-IdadeRESUMO
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.
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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/genéticaRESUMO
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.
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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/genéticaRESUMO
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.
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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 JovemRESUMO
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.
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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/genéticaRESUMO
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.
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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 JovemRESUMO
Fibrosis is the main cause of irreversible nerve damage in leprosy. Phenotypic changes in Mycobacterium leprae (ML)-infected Schwann cells (SCs) have been suggested to mediate this process. We found that SC line cultures stimulated with ML upregulated transforming growth factor-ß1 (TGF-ß1), and that TGF-ß1 or ML induced increased numbers of α-smooth muscle actin (α-SMA)-positive cells with characteristic stress fibers. Mycobacterium leprae and TGF-ß1 also induced increased type I collagen and fibronectin mRNA and secretion and augmented mRNA levels of SOX9 and ZEB1, which are involved in the epithelial-mesenchymal transition. These effects could be inhibited by the TGF-ß1 type I receptor (ALK5) inhibitor, SB-431542. In nerve biopsies from leprosy-infected patients with varying grades of fibrosis (n = 11), type I and III collagen and fibronectin were found in the endoneurium and perineurium, α-SMA-positive cells filled the fibrotic perineurium but not the endoneurium, and CD34-positive fibroblasts predominated in the endoneurium. Results of transcriptional studies of 3 leprosy nerves and 5 controls were consistent with these data, but α-SMA and other mRNA levels were not different from those in the control samples. Our findings suggest that TGF-ß1 may orchestrate events, including reprogramming of the SC phenotype, leading to transdifferentiation, connective tissue cell expansion, and fibrogenesis in the evolution of leprosy nerve lesions during some evolutionary stages.
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Hanseníase/patologia , Mycobacterium leprae , Neurônios/patologia , Fator de Crescimento Transformador beta1/fisiologia , Adulto , Diferenciação Celular/efeitos dos fármacos , Diferenciação Celular/fisiologia , Células Cultivadas , Feminino , Fibrose , Humanos , Mediadores da Inflamação/metabolismo , Hanseníase/metabolismo , Masculino , Pessoa de Meia-Idade , Neurônios/efeitos dos fármacos , Neurônios/metabolismo , Células de Schwann/efeitos dos fármacos , Células de Schwann/metabolismo , Células de Schwann/patologia , Fator de Crescimento Transformador beta1/toxicidade , Adulto JovemRESUMO
Lepromatous macrophages possess a regulatory phenotype that contributes to the immunosuppression observed in leprosy. CD163, a scavenger receptor that recognizes hemoglobin-haptoglobin complexes, is expressed at higher levels in lepromatous cells, although its functional role in leprosy is not yet established. We herein demonstrate that human lepromatous lesions are microenvironments rich in IDOâºCD163âº. Cells isolated from these lesions were CD68âºIDOâºCD163⺠while higher levels of sCD163 in lepromatous sera positively correlated with IL-10 levels and IDO activity. Different Myco-bacterium leprae (ML) concentrations in healthy monocytes likewise revealed a positive correlation between increased concentrations of the mycobacteria and IDO, CD209, and CD163 expression. The regulatory phenotype in ML-stimulated monocytes was accompanied by increased TNF, IL-10, and TGF-ß levels whereas IL-10 blockade reduced ML-induced CD163 expression. The CD163 blockade reduced ML uptake in human monocytes. ML uptake was higher in HEK293 cells transfected with the cDNA for CD163 than in untransfected cells. Simultaneously, increased CD163 expression in lepromatous cells seemed to be dependent on ML uptake, and contributed to augmented iron storage in lepromatous macrophages. Altogether, these results suggest that ML-induced CD163 expression modulates the host cell phenotype to create a favorable environment for myco-bacterial entry and survival.
Assuntos
Antígenos CD/imunologia , Antígenos de Diferenciação Mielomonocítica/imunologia , Hanseníase Virchowiana/imunologia , Hanseníase Virchowiana/microbiologia , Macrófagos/imunologia , Mycobacterium leprae/imunologia , Receptores de Superfície Celular/imunologia , Antígenos CD/genética , Antígenos de Diferenciação Mielomonocítica/genética , Biópsia , Citometria de Fluxo , Humanos , Indolamina-Pirrol 2,3,-Dioxigenase/imunologia , Interleucina-10/imunologia , Hanseníase Virchowiana/patologia , Macrófagos/microbiologia , RNA Mensageiro/química , RNA Mensageiro/genética , Receptores de Superfície Celular/genética , Reação em Cadeia da Polimerase Via Transcriptase ReversaRESUMO
OBJECTIVE: To analyze a profile of patients treated at a national leprosy outpatient referral clinic in metropolitan Rio de Janeiro, Brazil, over a period of more than two decades, and the subgroup of nationally registered leprosy cases from the same residential area, as well as all registered cases statewide. METHODS: An observational, descriptive analysis was carried out for patients treated from 1986 to 2007 at the Souza Araújo Outpatient Clinic (Ambulatório Souza Araújo, ASA), a national referral center for the diagnosis and treatment of leprosy at the Oswaldo Cruz Foundation (Fiocruz) that serves clients from the city of Rio de Janeiro and other municipalities in the metropolitan area of Rio de Janeiro State. Demographic and clinical data for the subgroup of leprosy cases registered with Brazil's National Disease Notification System (Sistema Nacional de Informação de Agravos de Notificação, SINAN) between 2001 and 2007 and residing in the same municipalities as the ASA patients, and for all registered cases statewide, were also analyzed. RESULTS: Among the ASA patients, there was a decrease in average family income (from 3.9 to 2.7 times the minimum salary between the periods 1998-2002 and 2003-2007); the proportion of multibacillary (MB) patients (from 52.7% to 46.9%); and the proportion of patients younger than 15 years old (from 12.8% to 8.7%). Among the MB patients, the average initial and final bacilloscopic indices were significantly higher in 2003-2007. Compared with the SINAN cases, more ASA cases involved disability and were younger than 15 years old. CONCLUSIONS: Patients living with leprosy in the metropolitan area of the state of Rio de Janeiro belong to the most deprived social strata and have not benefited from the overall improvement in socioeconomic conditions in Brazil.
Assuntos
Hanseníase/epidemiologia , Adolescente , Instituições de Assistência Ambulatorial , Brasil/epidemiologia , Feminino , Humanos , Masculino , Fatores SocioeconômicosRESUMO
BACKGROUND: Contacts of leprosy patients are at increased risk of developing leprosy and need to be targeted for early diagnosis. Seropositivity to the phenolic glycolipid I (PGL-I) antigen of Mycobacterium leprae has been used to identify contacts who have an increased risk of developing leprosy. In the present study, we studied the effect of seropositivity in patient contacts, on the risk of developing leprosy, stratified by Bacille Calmette Guerin (BCG) vaccination after index case diagnosis. METHODOLOGY/PRINCIPAL FINDINGS: Leprosy contacts were examined as part of the surveillance programme of the Oswaldo Cruz Institute Leprosy Outpatient Clinic in Rio de Janeiro. Demographic, social, epidemiological and clinical data were collected. The presence of IgM antibodies to PGL-I in sera and BCG vaccination status at the time of index case diagnosis were evaluated in 2,135 contacts. During follow-up, 60 (2.8%; 60/2,135) leprosy cases were diagnosed: 41 among the 1,793 PGL-I-negative contacts and 19 among the 342 PGL-I-positive contacts. Among PGL-I-positive contacts, BCG vaccination after index case diagnosis increased the adjusted rate of developing clinical manifestations of leprosy (Adjusted Rate Ratio (aRR)â=â4.1; 95% CI: 1.8-8.2) compared with the PGL-I-positive unvaccinated contacts (aRRâ=â3.2; 95% CI: 1.2-8.1). The incidence density was highest during the first year of follow-up for the PGL-I-positive vaccinated contacts. However, all of those contacts developed PB leprosy, whereas most MB cases (4/6) occurred in PGL-I-positive unvaccinated contacts. CONCLUSION: Contact examination combined with PGL-I testing and BCG vaccination remain important strategies for leprosy control. The finding that rates of leprosy cases were highest among seropositive contacts justifies targeting this specific group for close monitoring. Furthermore, it is recommended that PGL-I-positive contacts and contacts with a high familial bacteriological index, regardless of serological response, should be monitored. This group could be considered as a target for chemoprophylaxis.
Assuntos
Anticorpos Antibacterianos/sangue , Antígenos de Bactérias/imunologia , Vacina BCG/imunologia , Glicolipídeos/imunologia , Hanseníase/epidemiologia , Hanseníase/imunologia , Mycobacterium leprae/patogenicidade , Adolescente , Adulto , Idoso , Vacina BCG/administração & dosagem , Criança , Pré-Escolar , Estudos de Coortes , Humanos , Imunoglobulina M/sangue , Incidência , Lactente , Masculino , Pessoa de Meia-Idade , Mycobacterium leprae/imunologia , Medição de Risco , Adulto JovemRESUMO
BACKGROUND: Thalidomide is an anti-inflammatory and anti-angiogenic drug currently used for the treatment of several diseases, including erythema nodosum leprosum, which occurs in patients with lepromatous leprosy. In this research, we use DNA microarray analysis to identify the impact of thalidomide on gene expression responses in human cells after lipopolysaccharide (LPS) stimulation. We employed a two-stage framework. Initially, we identified 1584 altered genes in response to LPS. Modulation of this set of genes was then analyzed in the LPS stimulated cells treated with thalidomide. RESULTS: We identified 64 genes with altered expression induced by thalidomide using the rank product method. In addition, the lists of up-regulated and down-regulated genes were investigated by means of bioinformatics functional analysis, which allowed for the identification of biological processes affected by thalidomide. Confirmatory analysis was done in five of the identified genes using real time PCR. CONCLUSIONS: The results showed some genes that can further our understanding of the biological mechanisms in the action of thalidomide. Of the five genes evaluated with real time PCR, three were down regulated and two were up regulated confirming the initial results of the microarray analysis.