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1.
Front Immunol ; 12: 727580, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34621273

RESUMO

Despite being treatable, leprosy still represents a major public health problem, and many mechanisms that drive leprosy immunopathogenesis still need to be elucidated. B cells play important roles in immune defense, being classified in different subgroups that present distinct roles in the immune response. Here, the profile of B cell subpopulations in peripheral blood of patients with paucibacillary (TT/BT), multibacillary (LL/BL) and erythema nodosum leprosum was analyzed. B cell subpopulations (memory, transition, plasmablasts, and mature B cells) and levels of IgG were analyzed by flow cytometry and ELISA, respectively. It was observed that Mycobacterium leprae infection can alter the proportions of B cell subpopulations (increase of mature and decrease of memory B cells) in patients affected by leprosy. This modulation is associated with an increase in total IgG and the patient's clinical condition. Circulating B cells may be acting in the modulation of the immune response in patients with various forms of leprosy, which may reflect the patient's ability to respond to M. leprae.


Assuntos
Linfócitos B/imunologia , Hanseníase Multibacilar/imunologia , Adulto , Feminino , Humanos , Imunoglobulina G/sangue , Memória Imunológica , Hanseníase Multibacilar/sangue , Masculino , Pessoa de Meia-Idade , Fenótipo
2.
Front Immunol ; 12: 657449, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34456901

RESUMO

The respiratory tract is considered the main port of entry of Mycobacterium leprae, the causative agent of leprosy. However, the great majority of individuals exposed to the leprosy bacillus will never manifest the disease due to their capacity to develop protective immunity. Besides acting as a physical barrier, airway epithelium cells are recognized as key players by initiating a local innate immune response that orchestrates subsequent adaptive immunity to control airborne infections. However, to date, studies exploring the interaction of M. leprae with the respiratory epithelium have been scarce. In this work, the capacity of M. leprae to immune activate human alveolar epithelial cells was investigated, demonstrating that M. leprae-infected A549 cells secrete significantly increased IL-8 that is dependent on NF-κB activation. M. leprae was also able to induce IL-8 production in human primary nasal epithelial cells. M. leprae-treated A549 cells also showed higher expression levels of human ß-defensin-2 (hßD-2), MCP-1, MHC-II and the co-stimulatory molecule CD80. Furthermore, the TLR-9 antagonist inhibited both the secretion of IL-8 and NF-κB activation in response to M. leprae, indicating that bacterial DNA sensing by this Toll-like receptor constitutes an important innate immune pathway activated by the pathogen. Finally, evidence is presented suggesting that extracellular DNA molecules anchored to Hlp, a histone-like protein present on the M. leprae surface, constitute major TLR-9 ligands triggering this pathway. The ability of M. leprae to immune activate respiratory epithelial cells herein demonstrated may represent a very early event during infection that could possibly be essential to the generation of a protective response.


Assuntos
Células Epiteliais Alveolares/imunologia , Células Epiteliais Alveolares/metabolismo , Imunidade Inata , Hanseníase/imunologia , Hanseníase/metabolismo , Mycobacterium leprae/imunologia , Receptor Toll-Like 9/metabolismo , Células A549 , Biomarcadores , Células Cultivadas , Histonas/metabolismo , Interações Hospedeiro-Patógeno/imunologia , Humanos , Imunomodulação , Hanseníase/microbiologia , NF-kappa B/metabolismo
3.
Immunol Rev ; 301(1): 193-208, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-33913182

RESUMO

Leprosy is a much-feared incapacitating infectious disease caused by Mycobacterium leprae or M lepromatosis, annually affecting roughly 200,000 people worldwide. During host-pathogen interaction, M leprae subverts the immune response, leading to development of disease. Throughout the last few decades, the impact of energy metabolism on the control of intracellular pathogens and leukocytic differentiation has become more evident. Mitochondria play a key role in regulating newly-discovered immune signaling pathways by controlling redox metabolism and the flow of energy besides activating inflammasome, xenophagy, and apoptosis. Likewise, this organelle, whose origin is probably an alphaproteobacterium, directly controls the intracellular pathogens attempting to invade its niche, a feature conquered at the expense of billions of years of coevolution. In the present review, we discuss the role of reduced host cell mitochondrial activity during M leprae infection and the consequential fates of M leprae and host innate immunity. Conceivably, inhibition of mitochondrial energy metabolism emerges as an overlooked and novel mechanism developed by M leprae to evade xenophagy and the host immune response.


Assuntos
Hanseníase , Mycobacterium leprae , Interações Hospedeiro-Patógeno , Humanos , Imunidade Inata , Mitocôndrias
4.
Mem Inst Oswaldo Cruz ; 115: e200075, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32696914

RESUMO

BACKGROUND: Although Mycobacterium leprae (ML) is well characterised as the causative agent of leprosy, the pathophysiological mechanisms underlying peripheral nerve damage still need further understanding. In vitro and in vivo studies have yielded insights into molecular mechanisms of ML interaction with Schwann cells (SC), indicating the regulation of genes and proteins crucial to neural plasticity. OBJECTIVES: We aimed to investigate the effect of ML on neurotrophins expression in human SC (hSC) and mice sciatic nerves to better understand their role in leprosy neuropathy, and aiming to contribute to future therapeutic approaches. METHODS: We evaluated mRNA and protein expression of BDNF, NGF, NT-3, NT-4 in hSC from amputation nerve fragments, as well as in athymic nude mice, infected by ML for eight months. FINDINGS AND MAIN CONCLUSIONS: Our in vitro results showed a trend to decline in NGF and BDNF mRNA in ML-treated hSC, compared to controls. The immunodetection of BDNF and NT-4 was significantly downregulated in ML-treated hSC. Conversely, ML-infected mice demonstrated upregulation of NT-3, compared to non-infected animals. Our findings indicate that ML may be involved in neurotrophins regulation, suggesting that a pathogen-related imbalance of these growth factors may have a role in the neural impairment of leprosy.


Assuntos
Mycobacterium leprae , Fatores de Crescimento Neural/metabolismo , Células de Schwann/metabolismo , Nervo Isquiático/metabolismo , Animais , Humanos , Camundongos , Camundongos Nus
5.
F1000Res ; 92020.
Artigo em Inglês | MEDLINE | ID: mdl-32051758

RESUMO

Chronic infection by the obligate intracellular pathogen Mycobacterium leprae may lead to the development of leprosy. Of note, in the lepromatous clinical form of the disease, failure of the immune system to constrain infection allows the pathogen to reproduce to very high numbers with minimal clinical signs, favoring transmission. The bacillus can modulate cellular metabolism to support its survival, and these changes directly influence immune responses, leading to host tolerance, permanent disease, and dissemination. Among the metabolic changes, upregulation of cholesterol, phospholipids, and fatty acid biosynthesis is particularly important, as it leads to lipid accumulation in the host cells (macrophages and Schwann cells) in the form of lipid droplets, which are sites of polyunsaturated fatty acid-derived lipid mediator biosynthesis that modulate the inflammatory and immune responses. In Schwann cells, energy metabolism is also subverted to support a lipogenic environment. Furthermore, effects on tryptophan and iron metabolisms favor pathogen survival with moderate tissue damage. This review discusses the implications of metabolic changes on the course of M. leprae infection and host immune response and emphasizes the induction of regulatory T cells, which may play a pivotal role in immune modulation in leprosy.


Assuntos
Hanseníase , Colesterol , Progressão da Doença , Humanos , Mycobacterium leprae , Células de Schwann
6.
Cell Microbiol ; 22(1): e13128, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31652371

RESUMO

Leprosy neuropathy is a chronic degenerative infectious disorder of the peripheral nerve caused by the intracellular obligate pathogen Mycobacterium leprae (M. leprae). Among all nonneuronal cells that constitute the nerve, Schwann cells are remarkable in supporting M. leprae persistence intracellularly. Notably, the success of leprosy infection has been attributed to its ability in inducing the demyelination phenotype after contacting myelinated fibres. However, the exact role M. leprae plays during the ongoing process of myelin breakdown is entirely unknown. Here, we provided evidence showing an unexpected predilection of leprosy pathogen for degenerating myelin ovoids inside Schwann cells. In addition, M. leprae infection accelerated the rate of myelin breakdown and clearance leading to increased formation of lipid droplets, by modulating a set of regulatory genes involved in myelin maintenance, autophagy, and lipid storage. Remarkably, the blockage of myelin breakdown significantly reduced M. leprae content, demonstrating a new unpredictable role of myelin dismantling favouring M. leprae physiology. Collectively, our study provides novel evidence that may explain the demyelination phenotype as an evolutionarily conserved mechanism used by leprosy pathogen to persist longer in the peripheral nerve.


Assuntos
Mycobacterium leprae/fisiologia , Bainha de Mielina/metabolismo , Células de Schwann/microbiologia , Animais , Células Cultivadas , Humanos , Hanseníase/complicações , Hanseníase/microbiologia , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Mycobacterium leprae/patogenicidade , Bainha de Mielina/microbiologia
7.
s.l; s.n; 2020. 23 p. ilus, tab, graf.
Não convencional em Inglês | SES-SP, HANSEN, SESSP-ILSLACERVO, SES-SP | ID: biblio-1102413

RESUMO

The changes in host lipid metabolism during leprosy have been correlated to fatty acid alterations in serum and with high-density lipoprotein (HDL) dysfunctionality. This is most evident in multibacillary leprosy patients (Mb), who present an accumulation of host lipids in Schwann cells and macrophages. This accumulation in host peripheral tissues should be withdrawn by HDL, but it is unclear why this lipoprotein from Mb patients loses this function. To investigate HDL metabolism changes during the course of leprosy, HDL composition and functionality of Mb, Pb patients (paucibacillary) pre- or post-multidrug therapy (MDT) and HC (healthy controls) were analyzed. Mb pre-MDT patients presented lower levels of HDL-cholesterol compared to HC. Moreover, Ultra Performance Liquid Chromatography-Mass Spectrometry lipidomics of HDL showed an altered lipid profile of Mb pre-MDT compared to HC and Pb patients. In functional tests, HDL from Mb pre-MDT patients showed impaired anti-inflammatory and anti-oxidative stress activities and a lower cholesterol acceptor capacity compared to other groups. Mb pre-MDT showed lower concentrations of ApoA-I (apolipoprotein A-I), the major HDL protein, when compared to HC, with a post-MDT recovery. Changes in ApoA-I expression could also be observed in M. leprae-infected hepatic cells. The presence of bacilli in the liver of a Mb patient, along with cell damage, indicated hepatic involvement during leprosy, which may reflect on ApoA-I expression. Together, altered compositional and functional profiles observed on HDL of Mb patients can explain metabolic and physiological changes observed in Mb leprosy, contributing to a better understanding of its pathogenesis. AUTHOR SUMMARY: Leprosy is a chronic disease caused by Mycobacterium leprae, which causes lesions on the skin and peripheral nerves. Some patients do not present an efficient immune response and have a disseminated infection (multibacillary, Mb). Mb patients have lipid accumulation in infected tissues that is important for microorganism survival. High-density lipoprotein (HDL) is composed of proteins and lipids and is produced in the liver. It removes excess of lipids from peripheral tissues and presents anti-inflammatory activity; however, these activities are not being properly performed in leprosy. To understand more about HDL metabolism on leprosy, the chemical composition and functionality of HDL from leprosy patients were analyzed before and after treatment with antibiotics (multidrug therapy, MDT). It was observed that HDL has an altered lipid composition in Mb patients before MDT, which may lead to an impairment of its functions. Apolipoprotein A-I (ApoA-I), the main HDL protein, seems to be highly affected during infection. These functions can be slightly recovered after MDT, but not in the levels of healthy individuals. Our data open new perspectives to elucidate the modulation of lipid metabolism in leprosy and consequently to prevent disease complications.


Assuntos
Hanseníase/complicações , Hanseníase/metabolismo , Lipoproteínas HDL/metabolismo , Mycobacterium leprae/patogenicidade , Hepatopatias
8.
s.l; s.n; 2020. 8 p. graf.
Não convencional em Inglês | SES-SP, HANSEN, SESSP-ILSLPROD, SES-SP, SESSP-ILSLACERVO, SES-SP | ID: biblio-1102410

RESUMO

Leprosy neuropathy is a chronic degenerative infectious disorder of the peripheral nerve caused by the intracellular obligate pathogen Mycobacterium leprae (M. leprae). Among all nonneuronal cells that constitute the nerve, Schwann cells are remarkable in supporting M. leprae persistence intracellularly. Notably, the success of leprosy infection has been attributed to its ability in inducing the demyelination phenotype after contacting myelinated fibres. However, the exact role M. leprae plays during the ongoing process of myelin breakdown is entirely unknown. Here, we provided evidence showing an unexpected predilection of leprosy pathogen for degenerating myelin ovoids inside Schwann cells. In addition, M. leprae infection accelerated the rate of myelin breakdown and clearance leading to increased formation of lipid droplets, by modulating a set of regulatory genes involved in myelin maintenance, autophagy, and lipid storage. Remarkably, the blockage of myelin breakdown significantly reduced M. leprae content, demonstrating a new unpredictable role of myelin dismantling favouring M. leprae physiology. Collectively, our study provides novel evidence that may explain the demyelination phenotype as an evolutionarily conserved mechanism used by leprosy pathogen to persist longer in the peripheral nerve.


Assuntos
Células de Schwann/microbiologia , Doenças do Sistema Nervoso Periférico/metabolismo , Mycobacterium leprae/patogenicidade , Bainha de Mielina/microbiologia , Doenças Desmielinizantes/microbiologia , Hanseníase/complicações
9.
Rio de Janeiro; s.n; 2020. 11 p. ilus.
Não convencional em Inglês | SES-SP, CONASS, HANSEN, SESSP-ILSLPROD, SES-SP, SESSP-ILSLACERVO, SES-SP | ID: biblio-1146417

RESUMO

BACKGROUND: Although Mycobacterium leprae (ML) is well characterised as the causative agent of leprosy, the pathophysiological mechanisms underlying peripheral nerve damage still need further understanding. In vitro and in vivo studies have yielded insights into molecular mechanisms of ML interaction with Schwann cells (SC), indicating the regulation of genes and proteins crucial to neural plasticity. OBJECTIVES: We aimed to investigate the effect of ML on neurotrophins expression in human SC (hSC) and mice sciatic nerves to better understand their role in leprosy neuropathy, and aiming to contribute to future therapeutic approaches. METHODS: We evaluated mRNA and protein expression of BDNF, NGF, NT-3, NT-4 in hSC from amputation nerve fragments, as well as in athymic nude mice, infected by ML for eight months. FINDINGS and MAIN CONCLUSIONS: Our in vitro results showed a trend to decline in NGF and BDNF mRNA in ML-treated hSC, compared to controls. The immunodetection of BDNF and NT-4 was significantly downregulated in ML-treated hSC. Conversely, ML-infected mice demonstrated upregulation of NT-3, compared to non-infected animals. Our findings indicate that ML may be involved in neurotrophins regulation, suggesting that a pathogen-related imbalance of these growth factors may have a role in the neural impairment of leprosy(AU).


Assuntos
Humanos , Animais , Camundongos , Células de Schwann/imunologia , Mycobacterium leprae/imunologia , Doenças do Sistema Nervoso Periférico , Hanseníase/complicações , Fatores de Crescimento Neural
10.
mBio ; 10(6)2019 12 17.
Artigo em Inglês | MEDLINE | ID: mdl-31848273

RESUMO

New approaches are needed to control leprosy, but understanding of the biology of the causative agent Mycobacterium leprae remains rudimentary, principally because the pathogen cannot be grown in axenic culture. Here, we applied 13C isotopomer analysis to measure carbon metabolism of M. leprae in its primary host cell, the Schwann cell. We compared the results of this analysis with those of a related pathogen, Mycobacterium tuberculosis, growing in its primary host cell, the macrophage. Using 13C isotopomer analysis with glucose as the tracer, we show that whereas M. tuberculosis imports most of its amino acids directly from the host macrophage, M. leprae utilizes host glucose pools as the carbon source to biosynthesize the majority of its amino acids. Our analysis highlights the anaplerotic enzyme phosphoenolpyruvate carboxylase required for this intracellular diet of M. leprae, identifying this enzyme as a potential antileprosy drug target.IMPORTANCE Leprosy remains a major problem in the world today, particularly affecting the poorest and most disadvantaged sections of society in the least developed countries of the world. The long-term aim of research is to develop new treatments and vaccines, and these aims are currently hampered by our inability to grow the pathogen in axenic culture. In this study, we probed the metabolism of M. leprae while it is surviving and replicating inside its primary host cell, the Schwann cell, and compared it to a related pathogen, M. tuberculosis, replicating in macrophages. Our analysis revealed that unlike M. tuberculosis, M. leprae utilized host glucose as a carbon source and that it biosynthesized its own amino acids, rather than importing them from its host cell. We demonstrated that the enzyme phosphoenolpyruvate carboxylase plays a crucial role in glucose catabolism in M. leprae Our findings provide the first metabolic signature of M. leprae in the host Schwann cell and identify novel avenues for the development of antileprosy drugs.


Assuntos
Carbono/metabolismo , Glucose/metabolismo , Mycobacterium leprae/fisiologia , Células de Schwann/metabolismo , Células de Schwann/microbiologia , Metabolismo dos Carboidratos , Linhagem Celular , Interações Hospedeiro-Patógeno , Humanos , Hanseníase/metabolismo , Hanseníase/microbiologia , Macrófagos/metabolismo , Macrófagos/microbiologia , Redes e Vias Metabólicas
11.
PLoS Negl Trop Dis ; 13(9): e0007368, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-31504035

RESUMO

Up to 50% of patients with the multibacillary form of leprosy are expected to develop acute systemic inflammatory episodes known as type 2 reactions (T2R), thus aggravating their clinical status. Thalidomide rapidly improves T2R symptoms. But, due to its restricted use worldwide, novel alternative therapies are urgently needed. The T2R triggering mechanisms and immune-inflammatory pathways involved in its pathology remain ill defined. In a recent report, we defined the recognition of nucleic acids by TLR9 as a major innate immunity pathway that is activated during T2R. DNA recognition has been described as a major inflammatory pathway in several autoimmune diseases, and neutrophil DNA extracellular traps (NETs) have been shown to be a prime source of endogenous DNA. Considering that neutrophil abundance is a marked characteristic of T2R lesions, the objective of this study was to investigate NETs production in T2R patients based on the hypothesis that the excessive NETs formation would play a major role in T2R pathogenesis. Abundant NETs were found in T2R skin lesions, and increased spontaneous NETs formation was observed in T2R peripheral neutrophils. Both the M. leprae whole-cell sonicate and the CpG-Hlp complex, mimicking a mycobacterial TLR9 ligand, were able to induce NETs production in vitro. Moreover, TLR9 expression was shown to be higher in T2R neutrophils, suggesting that DNA recognition via TLR9 may be one of the pathways triggering this process during T2R. Finally, treatment of T2R patients with thalidomide for 7 consecutive days resulted in a decrease in all of the evaluated in vivo and ex vivo NETosis parameters. Altogether, our findings shed light on the pathogenesis of T2R, which, it is hoped, will contribute to the emergence of novel alternative therapies and the identification of prognostic reactional markers in the near future.


Assuntos
Armadilhas Extracelulares/imunologia , Imunidade Inata , Hanseníase/imunologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Doenças Autoimunes/imunologia , Doenças Autoimunes/microbiologia , Feminino , Humanos , Inflamação/imunologia , Inflamação/patologia , Hanseníase/tratamento farmacológico , Hanseníase/patologia , Masculino , Pessoa de Meia-Idade , Mycobacterium leprae/imunologia , Mycobacterium leprae/patogenicidade , Neutrófilos/patologia , Talidomida/administração & dosagem , Talidomida/uso terapêutico
12.
PLoS Negl Trop Dis ; 12(12): e0007001, 2018 12.
Artigo em Inglês | MEDLINE | ID: mdl-30566440

RESUMO

Leprosy is an infectious disease caused by Mycobacterium leprae and frequently resulting in irreversible deformities and disabilities. Ticks play an important role in infectious disease transmission due to their low host specificity, worldwide distribution, and the biological ability to support transovarial transmission of a wide spectrum of pathogens, including viruses, bacteria and protozoa. To investigate a possible role for ticks as vectors of leprosy, we assessed transovarial transmission of M. leprae in artificially-fed adult female Amblyomma sculptum ticks, and infection and growth of M. leprae in tick cell lines. Our results revealed M. leprae RNA and antigens persisting in the midgut and present in the ovaries of adult female A. sculptum at least 2 days after oral infection, and present in their progeny (eggs and larvae), which demonstrates the occurrence of transovarial transmission of this pathogen. Infected tick larvae were able to inoculate viable bacilli during blood-feeding on a rabbit. Moreover, following inoculation with M. leprae, the Ixodes scapularis embryo-derived tick cell line IDE8 supported a detectable increase in the number of bacilli for at least 20 days, presenting a doubling time of approximately 12 days. As far as we know, this is the first in vitro cellular system able to promote growth of M. leprae. Finally, we successfully transformed a clinical M. leprae isolate by inserting the reporter plasmid pCHERRY3; transformed bacteria infected and grew in IDE8 cells over a 2-month period. Taken together, our data not only support the hypothesis that ticks may have the potential to act as a reservoir and/or vector of leprosy, but also suggest the feasibility of technological development of tick cell lines as a tool for large-scale production of M. leprae bacteria, as well as describing for the first time a method for their transformation.


Assuntos
Vetores Aracnídeos/fisiologia , Ixodes/microbiologia , Ixodidae/microbiologia , Hanseníase/transmissão , Mycobacterium leprae/fisiologia , Animais , Vetores Aracnídeos/microbiologia , Linhagem Celular , Feminino , Humanos , Ixodes/fisiologia , Ixodidae/fisiologia , Hanseníase/microbiologia , Masculino , Mycobacterium leprae/genética , Coelhos
13.
PLoS Pathog ; 14(7): e1007151, 2018 07.
Artigo em Inglês | MEDLINE | ID: mdl-29979790

RESUMO

Mycobacterium leprae, an obligate intracellular bacillus, infects Schwann cells (SCs), leading to peripheral nerve damage, the most severe leprosy symptom. In the present study, we revisited the involvement of phenolic glycolipid I (PGL I), an abundant, private, surface M. leprae molecule, in M. leprae-SC interaction by using a recombinant strain of M. bovis BCG engineered to express this glycolipid. We demonstrate that PGL I is essential for bacterial adhesion and SC internalization. We also show that live mycobacterium-producing PGL I induces the expression of the endocytic mannose receptor (MR/CD206) in infected cells in a peroxisome proliferator-activated receptor gamma (PPARγ)-dependent manner. Of note, blocking mannose recognition decreased bacterial entry and survival, pointing to a role for this alternative recognition pathway in bacterial pathogenesis in the nerve. Moreover, an active crosstalk between CD206 and the nuclear receptor PPARγ was detected that led to the induction of lipid droplets (LDs) formation and prostaglandin E2 (PGE2), previously described as fundamental players in bacterial pathogenesis. Finally, this pathway was shown to induce IL-8 secretion. Altogether, our study provides evidence that the entry of live M. leprae through PGL I recognition modulates the SC phenotype, favoring intracellular bacterial persistence with the concomitant secretion of inflammatory mediators that may ultimately be involved in neuroinflammation.


Assuntos
Antígenos de Bactérias/metabolismo , Glicolipídeos/metabolismo , Lectinas Tipo C/metabolismo , Hanseníase/metabolismo , Lectinas de Ligação a Manose/metabolismo , PPAR gama/metabolismo , Receptores de Superfície Celular/metabolismo , Células de Schwann/virologia , Humanos , Mycobacterium leprae/metabolismo , Receptor Cross-Talk/fisiologia
14.
Cytokine ; 112: 87-94, 2018 12.
Artigo em Inglês | MEDLINE | ID: mdl-30017389

RESUMO

The disease leprosy is caused by Mycobacterium leprae. The disease displays a spectrum of clinical manifestations relating to the stage of the infection and the pathogen-specific immune response. The most frequent M. leprae-specific hypersensitivity reactions are erythema nodosum leprosum (ENL) and type-1 (reversal) reaction (T1R). Omega-3 and omega-6 fatty acid-derived lipid mediators are involved in the regulation of these M. leprae-specific inflammatory and immune responses. Studies on lipid mediators showed their presence during different manifestations of leprosy-before and after multidrug therapy (MDT) and during T1R. This review aims to compare the lipid mediators at different stages of the disease. This review also presents new data on the significance of lipid mediators (cysteinyl leukotrienes and leukotriene B4, prostaglandin E2 and D2, lipoxin A4 and resolvin D1) on ENL.


Assuntos
Ácidos Graxos Ômega-3/sangue , Ácidos Graxos Ômega-6/sangue , Hanseníase/sangue , Animais , Quimioterapia Combinada , Eritema Nodoso/sangue , Eritema Nodoso/tratamento farmacológico , Humanos , Hansenostáticos/farmacologia , Hanseníase/tratamento farmacológico , Mycobacterium leprae/efeitos dos fármacos
15.
Front Immunol ; 9: 518, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29643852

RESUMO

Leprosy is an infectious disease that may present different clinical forms depending on host immune response to Mycobacterium leprae. Several studies have clarified the role of various T cell populations in leprosy; however, recent evidences suggest that local innate immune mechanisms are key determinants in driving the disease to its different clinical manifestations. Leprosy is an ideal model to study the immunoregulatory role of innate immune molecules and its interaction with nervous system, which can affect homeostasis and contribute to the development of inflammatory episodes during the course of the disease. Macrophages, dendritic cells, neutrophils, and keratinocytes are the major cell populations studied and the comprehension of the complex networking created by cytokine release, lipid and iron metabolism, as well as antimicrobial effector pathways might provide data that will help in the development of new strategies for leprosy management.


Assuntos
Imunidade Inata , Hanseníase/imunologia , Animais , Humanos , Hanseníase/patologia , Hanseníase/transmissão , Mycobacterium leprae/fisiologia
16.
PLoS Negl Trop Dis ; 12(3): e0006214, 2018 03.
Artigo em Inglês | MEDLINE | ID: mdl-29565968

RESUMO

BACKGROUND: Leprosy is a chronic dermato-neurological disease caused by Mycobacterium leprae infection. In 2016, more than 200,000 new cases of leprosy were detected around the world, representing the most frequent cause of infectious irreversible deformities and disabilities. PRINCIPAL FINDINGS: In the present work, we demonstrate a consistent procoagulant profile on 40 reactional and non-reactional multibacillary leprosy patients. A retrospective analysis in search of signs of coagulation abnormalities among 638 leprosy patients identified 35 leprosy patients (5.48%) which displayed a characteristic lipid-like clot formed between blood clot and serum during serum harvesting, herein named 'leprosum clot'. Most of these patients (n = 16, 45.7%) belonged to the lepromatous leprosy pole of the disease. In addition, formation of the leprosum clot was directly correlated with increased plasma levels of soluble tissue factor and von Willebrand factor. High performance thin layer chromatography demonstrated a high content of neutral lipids in the leprosum clot, and proteomic analysis demonstrated that the leprosum clot presented in these patients is highly enriched in fibrin. Remarkably, differential 2D-proteomics analysis between leprosum clots and control clots identified two proteins present only in leprosy patients clots: complement component 3 and 4 and inter-alpha-trypsin inhibitor family heavy chain-related protein (IHRP). In agreement with those observations we demonstrated that M. leprae induces hepatocytes release of IHRP in vitro. CONCLUSIONS: We demonstrated that leprosy MB patients develop a procoagulant status due to high levels of plasmatic fibrinogen, anti-cardiolipin antibodies, von Willebrand factor and soluble tissue factor. We propose that some of these components, fibrinogen for example, presents potential as predictive biomarkers of leprosy reactions, generating tools for earlier diagnosis and treatment of these events.


Assuntos
Transtornos da Coagulação Sanguínea/microbiologia , Eritema Nodoso/sangue , Hanseníase Virchowiana/sangue , Pele/microbiologia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Biomarcadores/sangue , Brasil , Criança , Eletroforese em Gel Bidimensional , Eletroforese em Gel de Poliacrilamida , Eritema Nodoso/complicações , Feminino , Humanos , Hanseníase Virchowiana/complicações , Modelos Lineares , Masculino , Espectrometria de Massas , Pessoa de Meia-Idade , Mycobacterium leprae/isolamento & purificação , Estudos Prospectivos , Proteômica/métodos , Estudos Retrospectivos , Adulto Jovem
17.
s.l; s.n; 2018. 25 p. ilu, tab, graf.
Não convencional em Inglês | SES-SP, HANSEN, SESSP-ILSLPROD, SES-SP, SESSP-ILSLACERVO, SES-SP | ID: biblio-1025298

RESUMO

Leprosy is an infectious disease caused by Mycobacterium leprae and frequently resulting in irreversible deformities and disabilities. Ticks play an important role in infectious disease transmission due to their low host specificity, worldwide distribution, and the biological ability to support transovarial transmission of a wide spectrum of pathogens, including viruses, bacteria and protozoa. To investigate a possible role for ticks as vectors of leprosy, we assessed transovarial transmission of M. leprae in artificially-fed adult female Amblyomma sculptum ticks, and infection and growth of M. leprae in tick cell lines. Our results revealed M. leprae RNA and antigens persisting in the midgut and present in the ovaries of adult female A. sculptum at least 2 days after oral infection, and present in their progeny (eggs and larvae), which demonstrates the occurrence of transovarial transmission of this pathogen. Infected tick larvae were able to inoculate viable bacilli during blood-feeding on a rabbit. Moreover, following inoculation with M. leprae, the Ixodes scapularis embryo-derived tick cell line IDE8 supported a detectable increase in the number of bacilli for at least 20 days, presenting a doubling time of approximately 12 days. As far as we know, this is the first in vitro cellular system able to promote growth of M. leprae. Finally, we successfully transformed a clinical M. leprae isolate by inserting the reporter plasmid pCHERRY3; transformed bacteria infected and grew in IDE8 cells over a 2-month period. Taken together, our data not only support the hypothesis that ticks may have the potential to act as a reservoir and/or vector of leprosy, but also suggest the feasibility of technological development of tick cell lines as a tool for large-scale production of M. leprae bacteria, as well as describing for the first time a method for their transformation.


Assuntos
Humanos , Animais , Masculino , Feminino , Coelhos , Vetores Aracnídeos/fisiologia , Vetores Aracnídeos/microbiologia , Linhagem Celular , Ixodes/fisiologia , Ixodes/microbiologia , Ixodidae/fisiologia , Ixodidae/microbiologia , Hanseníase/microbiologia , Hanseníase/transmissão , Mycobacterium leprae/fisiologia , Mycobacterium leprae/genética
18.
s.l; s.n; 2018. 20 p. ilus, tab, graf.
Não convencional em Inglês | SES-SP, HANSEN, SESSP-ILSLPROD, SES-SP, SESSP-ILSLACERVO, SES-SP | ID: biblio-1023805

RESUMO

Hemostatic illnesses are frequently associated with acute and chronic infections. In the present work we demonstrated that leprosy patients developed hemostatic abnormalities, like the formation of an atypical lipid clot mass during sera harvesting, a phenomenon previously observed and never unraveled. We characterize the nature of the "leprosum clot", formed during a protrombotic state developed by some patients. During the proteomic analysis of the leprosum clot we discovered a set of potential serum biomarkers to leprosy reactional episodes diagnosis, which at this moment is based only in clinical features. Taking together, our data suggest that leprosy patients are suffering from a procoagulant status, being beneficiated by the introduction of routine coagulation tests during their treatment, which will aloud physicians to prevent some of the acute clinical symptoms related with superficial vein thrombosis such as cyanosis and tissue necrosis observed during severe cases of leprosy reactional episodes. (AU)


Assuntos
Humanos , Masculino , Feminino , Criança , Adolescente , Adulto , Pessoa de Meia-Idade , Idoso , Idoso de 80 Anos ou mais , Adulto Jovem , Pele/microbiologia , Espectrometria de Massas , Transtornos da Coagulação Sanguínea/microbiologia , Biomarcadores/sangue , Eletroforese em Gel Bidimensional , Hanseníase Virchowiana/complicações , Hanseníase Virchowiana/sangue , Modelos Lineares , Proteômica/métodos , Eletroforese em Gel de Poliacrilamida , Eritema Nodoso/complicações , Eritema Nodoso/sangue , Mycobacterium leprae/isolamento & purificação , Estudos Prospectivos , Estudos Retrospectivos
19.
PLoS Negl Trop Dis ; 11(5): e0005560, 2017 May.
Artigo em Inglês | MEDLINE | ID: mdl-28467415

RESUMO

Household contacts of multibacillary leprosy patients (HCMB) constitute the group of individuals at the highest risk of developing leprosy. Early diagnosis and treatment of their index cases combined with Bacille Calmette-Guerin (BCG) immunization remain important strategies adopted in Brazil to prevent HCMB from evolving into active disease. In the present study, we assessed the impact of these measures on the immune response to Mycobacterium leprae in HCMB. Peripheral blood mononuclear cells (PBMC) from HCMB (n = 16) were obtained at the beginning of leprosy index case treatment (T0). At this time point, contacts were vaccinated (n = 13) or not (n = 3) in accordance with their infancy history of BCG vaccination and PBMCs were recollected at least 6 months later (T1). As expected, a significant increase in memory CD4 and CD8 T cell frequencies responsive to M. leprae whole-cell sonicate was observed in most contacts. Of note, higher frequencies of CD4+ T cells that recognize M. leprae specific epitopes were also detected. Moreover, increased production of the inflammatory mediators IL1-ß, IL-6, IL-17, TNF, IFN-γ, MIP1-ß, and MCP-1 was found at T1. Interestingly, the increment in these parameters was observed even in those contacts that were not BCG vaccinated at T0. This result reinforces the hypothesis that the continuous exposure of HCMB to live M. leprae down regulates the specific cellular immune response against the pathogen. Moreover, our data suggest that BCG vaccination of HCMB induces activation of T cell clones, likely through "trained immunity", that recognize M. leprae specific antigens not shared with BCG as an additional protective mechanism besides the expected boost in cell-mediated immunity by BCG homologues of M. leprae antigens.


Assuntos
Antígenos de Bactérias/imunologia , Vacina BCG/uso terapêutico , Linfócitos T CD4-Positivos/imunologia , Imunidade Celular , Hanseníase Multibacilar/imunologia , Adulto , Anticorpos Antibacterianos/sangue , Brasil , Linfócitos T CD8-Positivos/imunologia , Citocinas/metabolismo , Epitopos de Linfócito T/imunologia , Características da Família , Feminino , Humanos , Imunoglobulina M/sangue , Hanseníase Multibacilar/prevenção & controle , Ativação Linfocitária , Masculino , Pessoa de Meia-Idade , Mycobacterium leprae , Estudos Prospectivos , Adulto Jovem
20.
J Infect Dis ; 215(3): 431-439, 2017 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-27932613

RESUMO

Background: Type 1 reaction (T1R) is an acute T-helper type 1 (Th1) inflammatory episode in patients with leprosy. While immunological responses associated with T1R have been investigated, the corresponding metabolic responses that could contribute to T1R pathology have received little attention. Methods: Metabolomics-based analyses of sera from 7 patients with and 9 without T1R were conducted via liquid chromatography-mass spectrometry. Serum metabolites present at levels that significantly differed (P < .05) with a log2 fold change of ≥ 1.0 between patient groups were interrogated against known metabolic pathways. The structural identification of targeted metabolites was confirmed and abundance changes validated by mass spectrometry and enzyme-linked immunoassay. Results: Forty metabolic pathways were perturbed in patients with T1R, with 71 dysregulated metabolites mapping to pathways for lipid mediators of inflammation. Of note was an increase in the abundance of the proinflammatory leukotriene B4 (LTB4) and a corresponding decrease in the level of proresolving resolvin D1 (RvD1). Also, levels of prostaglandin D2 (PGD2) and lipoxin A4 (LXA4) in patients with T1R were significantly increased, while the level of prostaglandin E2 (PGE2) was decreased. Conclusions: The dysregulation of metabolic pathways leading to abundance shifts between proinflammatory and proresolving lipid mediators provides a link between metabolic and cellular immune responses that result in the Th1-mediated pathology of T1R.


Assuntos
Mediadores da Inflamação/metabolismo , Hanseníase/imunologia , Lipídeos/imunologia , Células Th1/imunologia , Adulto , Idoso , Antígenos de Bactérias/imunologia , Cromatografia Líquida , Ácidos Graxos Insaturados/imunologia , Feminino , Glicolipídeos/imunologia , Humanos , Hanseníase/metabolismo , Masculino , Espectrometria de Massas , Redes e Vias Metabólicas , Metabolômica , Pessoa de Meia-Idade , Mycobacterium leprae/imunologia
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