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1.
BMJ Open ; 10(11): e037700, 2020 11 17.
Article in English | MEDLINE | ID: mdl-33203627

ABSTRACT

INTRODUCTION: Erythema nodosum leprosum (ENL) is an immunological complication of leprosy. ENL results in morbidity and disability and if it is not treated can lead to death. The current treatment consists of thalidomide or high doses of oral corticosteroids for prolonged periods. Thalidomide is not available in many leprosy endemic countries. The use of corticosteroids is associated with morbidity and mortality. Identifying treatment regimens that reduce the use of corticosteroids in ENL is essential. Methotrexate (MTX) is used to treat many inflammatory diseases and has been used successfully to treat patients with ENL not controlled by other drugs, including prednisolone and thalidomide. We present the protocol of the 'MTX and prednisolone study in ENL' (MaPs in ENL) a randomised controlled trial (RCT) designed to test the efficacy of MTX in the management of ENL. METHODS AND ANALYSIS: MaPs in ENL is an international multicentre RCT, which will be conducted in leprosy referral centres in Bangladesh, Brazil, Ethiopia, India, Indonesia and Nepal. Patients diagnosed with ENL who consent to participate will be randomly allocated to receive 48 weeks of weekly oral MTX plus 20 weeks of prednisolone or 48 weeks of placebo plus 20 weeks of prednisolone. Participants will be stratified by type of ENL into those with acute ENL and those with chronic and recurrent ENL. The primary objective is to determine whether MTX reduces the requirement for additional prednisolone. Patients' reported outcome measures will be used to assess the efficacy of MTX. Participants will be closely monitored for adverse events. ETHICS AND DISSEMINATION: Results will be submitted for publication in peer-reviewed journals. Ethical approval was obtained from the Observational/Interventions Research Ethics Committee of the London School of Hygiene & Tropical Medicine (15762); The Leprosy Mission International Bangladesh Institutional Research Board (in process); AHRI-ALERT Ethical Review Committee, Ethiopia; Ethics Committee of the Managing Committee of the Bombay Leprosy Project; and The Leprosy Mission Trust India Ethics Committee; the Nepal Health and Research Council and Health Research Ethics Committee Dr. Soetomo, Indonesia. This study is registered at www.clinicaltrials.gov. This is the first RCT of MTX for ENL and will contribute to the evidence for the management of ENL.Trial registration numberNCT 03775460.


Subject(s)
Erythema Nodosum , Leprosy, Lepromatous , Methotrexate/therapeutic use , Prednisolone/therapeutic use , Bangladesh , Brazil , Erythema Nodosum/drug therapy , Ethiopia , Humans , India , Indonesia , Leprostatic Agents/therapeutic use , Leprosy, Lepromatous/drug therapy , London , Nepal
2.
Sci Rep ; 9(1): 17931, 2019 11 29.
Article in English | MEDLINE | ID: mdl-31784594

ABSTRACT

Early diagnosis of leprosy is challenging, particularly its inflammatory reactions, the major cause of irreversible neuropathy in leprosy. Current diagnostics cannot identify which patients are at risk of developing reactions. This study assessed blood RNA expression levels as potential biomarkers for leprosy. Prospective cohorts of newly diagnosed leprosy patients, including reactions, and healthy controls were recruited in Bangladesh, Brazil, Ethiopia and Nepal. RNA expression in 1,090 whole blood samples was determined for 103 target genes for innate and adaptive immune profiling by dual color Reverse-Transcription Multiplex Ligation-dependent Probe Amplification (dcRT-MLPA) followed by cluster analysis. We identified transcriptomic biomarkers associated with leprosy disease, different leprosy phenotypes as well as high exposure to Mycobacterium leprae which respectively allow improved diagnosis and classification of leprosy patients and detection of infection. Importantly, a transcriptomic signature of risk for reversal reactions consisting of five genes (CCL2, CD8A, IL2, IL15 and MARCO) was identified based on cross-sectional comparison of RNA expression. In addition, intra-individual longitudinal analyses of leprosy patients before, during and after treatment of reversal reactions, indicated that several IFN-induced genes increased significantly at onset of reaction whereas IL15 decreased. This multi-site study, situated in four leprosy endemic areas, demonstrates the potential of host transcriptomic biomarkers as correlates of risk for leprosy. Importantly, a prospective five-gene signature for reversal reactions could predict reversal reactions at least 2 weeks before onset. Thus, transcriptomic biomarkers provide promise for early detection of these acute inflammatory episodes and thereby help prevent permanent neuropathy and disability in leprosy patients.


Subject(s)
Leprosy/genetics , Transcriptome , Adolescent , Adult , Bangladesh/epidemiology , Biomarkers/blood , Brazil/epidemiology , Ethiopia/epidemiology , Female , Humans , Leprosy/blood , Leprosy/epidemiology , Male , Mycobacterium leprae/isolation & purification , Nepal/epidemiology , Netherlands/epidemiology , Prognosis , Prospective Studies , Young Adult
3.
BMC Infect Dis ; 15: 477, 2015 Oct 28.
Article in English | MEDLINE | ID: mdl-26510990

ABSTRACT

BACKGROUND: Acute inflammatory reactions are a frequently occurring, tissue destructing phenomenon in infectious- as well as autoimmune diseases, providing clinical challenges for early diagnosis. In leprosy, an infectious disease initiated by Mycobacterium leprae (M. leprae), these reactions represent the major cause of permanent neuropathy. However, laboratory tests for early diagnosis of reactional episodes which would significantly contribute to prevention of tissue damage are not yet available. Although classical diagnostics involve a variety of tests, current research utilizes limited approaches for biomarker identification. In this study, we therefore studied leprosy as a model to identify biomarkers specific for inflammatory reactional episodes. METHODS: To identify host biomarker profiles associated with early onset of type 1 leprosy reactions, prospective cohorts including leprosy patients with and without reactions were recruited in Bangladesh, Brazil, Ethiopia and Nepal. The presence of multiple cyto-/chemokines induced by M. leprae antigen stimulation of peripheral blood mononuclear cells as well as the levels of antibodies directed against M. leprae-specific antigens in sera, were measured longitudinally in patients. RESULTS: At all sites, longitudinal analyses showed that IFN-γ-, IP-10-, IL-17- and VEGF-production by M. leprae (antigen)-stimulated PBMC peaked at diagnosis of type 1 reactions, compared to when reactions were absent. In contrast, IL-10 production decreased during type 1 reaction while increasing after treatment. Thus, ratios of these pro-inflammatory cytokines versus IL-10 provide useful tools for early diagnosing type 1 reactions and evaluating treatment. Of further importance for rapid diagnosis, circulating IP-10 in sera were significantly increased during type 1 reactions. On the other hand, humoral immunity, characterized by M. leprae-specific antibody detection, did not identify onset of type 1 reactions, but allowed treatment monitoring instead. CONCLUSIONS: This study identifies immune-profiles as promising host biomarkers for detecting intra-individual changes during acute inflammation in leprosy, also providing an approach for other chronic (infectious) diseases to help early diagnose these episodes and contribute to timely treatment and prevention of tissue damage.


Subject(s)
Biomarkers/analysis , Cytokines/immunology , Leprosy/immunology , Mycobacterium leprae/pathogenicity , Bangladesh , Brazil , Cytokines/blood , Ethiopia , Female , Host-Pathogen Interactions , Humans , Immunity, Humoral/immunology , Interleukin-10/blood , Interleukin-17/blood , Leprosy/diagnosis , Leukocytes, Mononuclear/immunology , Leukocytes, Mononuclear/microbiology , Male , Middle Aged , Mycobacterium leprae/immunology , Nepal , Prospective Studies
4.
Mem. Inst. Oswaldo Cruz ; 107(supl.1): 112-123, Dec. 2012. ilus, graf, tab
Article in English | LILACS | ID: lil-659749

ABSTRACT

Silent transmission of Mycobacterium leprae, as evidenced by stable leprosy incidence rates in various countries, remains a health challenge despite the implementation of multidrug therapy worldwide. Therefore, the development of tools for the early diagnosis of M. leprae infection should be emphasised in leprosy research. As part of the continuing effort to identify antigens that have diagnostic potential, unique M. leprae peptides derived from predicted virulence-associated proteins (group IV.A) were identified using advanced genome pattern programs and bioinformatics. Based on human leukocyte antigen (HLA)-binding motifs, we selected 21 peptides that were predicted to be promiscuous HLA-class I T-cell epitopes and eight peptides that were predicted to be HLA-class II restricted T-cell epitopes for field-testing in Brazil, Ethiopia and Nepal. High levels of interferon (IFN)-γ were induced when peripheral blood mononuclear cells (PBMCs) from tuberculoid/borderline tuberculoid leprosy patients located in Brazil and Ethiopia were stimulated with the ML2055 p35 peptide. PBMCs that were isolated from healthy endemic controls living in areas with high leprosy prevalence (EChigh) in Ethiopia also responded to the ML2055 p35 peptide. The Brazilian EChigh group recognised the ML1358 p20 and ML1358 p24 peptides. None of the peptides were recognised by PBMCs from healthy controls living in non-endemic region. In Nepal, mixtures of these peptides induced the production of IFN-γ by the PBMCs of leprosy patients and EChigh. Therefore, the M. leprae virulence-associated peptides identified in this study may be useful for identifying exposure to M. leprae in population with differing HLA polymorphisms.


Subject(s)
Humans , Cytokines/immunology , Epitopes, T-Lymphocyte/immunology , Mycobacterium leprae/pathogenicity , Virulence/immunology , Brazil , Bacterial Proteins/immunology , Computational Biology , Epitope Mapping , Ethiopia , Mycobacterium leprae/immunology , Mycobacterium leprae/isolation & purification , Mycobacterium leprae/virology , Nepal , Peptide Fragments/immunology , Recombinant Proteins/immunology
5.
Mem. Inst. Oswaldo Cruz ; 107(supl.1): 124-131, Dec. 2012. tab
Article in English | LILACS | ID: lil-659750

ABSTRACT

The diagnosis of leprosy continues to be based on clinical symptoms and early diagnosis and treatment are critical to preventing disability and transmission. Sensitive and specific laboratory tests are not available for diagnosing leprosy. Despite the limited applicability of anti-phenolic glycolipid-I (PGL-I) serology for diagnosis, it has been suggested as an additional tool to classify leprosy patients (LPs) for treatment purposes. Two formats of rapid tests to detect anti-PGL-I antibodies [ML immunochromatography assay (ICA) and ML Flow] were compared in different groups, multibacillary patients, paucibacillary patients, household contacts and healthy controls in Brazil and Nepal. High ML Flow intra-test concordance was observed and low to moderate agreement between the results of ML ICA and ML Flow tests on the serum of LPs was observed. LPs were "seroclassified" according to the results of these tests and the seroclassification was compared to other currently used classification systems: the World Health Organization operational classification, the bacilloscopic index and the Ridley-Jopling classification. When analysing the usefulness of these tests in the operational classification of PB and MB leprosy for treatment and follow-up purposes, the ML Flow test was the best point-of-care test for subjects in Nepal and despite the need for sample dilution, the ML ICA test yielded better performance among Brazilian subjects. Our results identified possible ways to improve the performance of both tests.


Subject(s)
Adolescent , Adult , Aged , Aged, 80 and over , Child , Child, Preschool , Female , Humans , Male , Middle Aged , Young Adult , Antigens, Bacterial/blood , Glycolipids/blood , Immunoglobulin Isotypes/blood , Leprosy/diagnosis , Mycobacterium leprae/immunology , Brazil , Case-Control Studies , Immunoassay/methods , Chromatography, Affinity/methods , Leprosy/immunology , Nepal , Predictive Value of Tests , Reagent Kits, Diagnostic , Sensitivity and Specificity
6.
Mem. Inst. Oswaldo Cruz ; 107(supl.1): 197-208, Dec. 2012. ilus, tab
Article in English | LILACS | ID: lil-659759

ABSTRACT

A variety of host immunogenetic factors appear to influence both an individual's susceptibility to infection with Mycobacterium leprae and the pathologic course of the disease. Animal models can contribute to a better understanding of the role of immunogenetics in leprosy through comparative studies helping to confirm the significance of various identified traits and in deciphering the underlying mechanisms that may be involved in expression of different disease related phenotypes. Genetically engineered mice, with specific immune or biochemical pathway defects, are particularly useful for investigating granuloma formation and resistance to infection and are shedding new light on borderline areas of the leprosy spectrum which are clinically unstable and have a tendency toward immunological complications. Though armadillos are less developed in this regard, these animals are the only other natural hosts of M. leprae and they present a unique opportunity for comparative study of genetic markers and mechanisms associable with disease susceptibility or resistance, especially the neurological aspects of leprosy. In this paper, we review the recent contributions of genetically engineered mice and armadillos toward our understanding of the immunogenetics of leprosy.


Subject(s)
Animals , Mice , Animals, Genetically Modified , Armadillos/genetics , Disease Models, Animal , Immunogenetic Phenomena/immunology , Leprosy/genetics , Leprosy/immunology , Mycobacterium leprae , Mice/genetics , Armadillos/microbiology , Mycobacterium leprae/genetics , Mycobacterium leprae/immunology
7.
Mem Inst Oswaldo Cruz ; 107 Suppl 1: 112-23, 2012 Dec.
Article in English | MEDLINE | ID: mdl-23283462

ABSTRACT

Silent transmission of Mycobacterium leprae, as evidenced by stable leprosy incidence rates in various countries, remains a health challenge despite the implementation of multidrug therapy worldwide. Therefore, the development of tools for the early diagnosis of M. leprae infection should be emphasised in leprosy research. As part of the continuing effort to identify antigens that have diagnostic potential, unique M. leprae peptides derived from predicted virulence-associated proteins (group IV.A) were identified using advanced genome pattern programs and bioinformatics. Based on human leukocyte antigen (HLA)-binding motifs, we selected 21 peptides that were predicted to be promiscuous HLA-class I T-cell epitopes and eight peptides that were predicted to be HLA-class II restricted T-cell epitopes for field-testing in Brazil, Ethiopia and Nepal. High levels of interferon (IFN)-γ were induced when peripheral blood mononuclear cells (PBMCs) from tuberculoid/borderline tuberculoid leprosy patients located in Brazil and Ethiopia were stimulated with the ML2055 p35 peptide. PBMCs that were isolated from healthy endemic controls living in areas with high leprosy prevalence (EChigh) in Ethiopia also responded to the ML2055 p35 peptide. The Brazilian EChigh group recognised the ML1358 p20 and ML1358 p24 peptides. None of the peptides were recognised by PBMCs from healthy controls living in non-endemic region. In Nepal, mixtures of these peptides induced the production of IFN-γ by the PBMCs of leprosy patients and EChigh. Therefore, the M. leprae virulence-associated peptides identified in this study may be useful for identifying exposure to M. leprae in population with differing HLA polymorphisms.


Subject(s)
Cytokines/immunology , Epitopes, T-Lymphocyte/immunology , Mycobacterium leprae/pathogenicity , Virulence/immunology , Bacterial Proteins/immunology , Brazil , Computational Biology , Epitope Mapping , Ethiopia , Humans , Mycobacterium leprae/immunology , Mycobacterium leprae/isolation & purification , Mycobacterium leprae/virology , Nepal , Peptide Fragments/immunology , Recombinant Proteins/immunology
8.
Mem Inst Oswaldo Cruz ; 107 Suppl 1: 124-31, 2012 Dec.
Article in English | MEDLINE | ID: mdl-23283463

ABSTRACT

The diagnosis of leprosy continues to be based on clinical symptoms and early diagnosis and treatment are critical to preventing disability and transmission. Sensitive and specific laboratory tests are not available for diagnosing leprosy. Despite the limited applicability of anti-phenolic glycolipid-I (PGL-I) serology for diagnosis, it has been suggested as an additional tool to classify leprosy patients (LPs) for treatment purposes. Two formats of rapid tests to detect anti-PGL-I antibodies [ML immunochromatography assay (ICA) and ML Flow] were compared in different groups, multibacillary patients, paucibacillary patients, household contacts and healthy controls in Brazil and Nepal. High ML Flow intra-test concordance was observed and low to moderate agreement between the results of ML ICA and ML Flow tests on the serum of LPs was observed. LPs were "seroclassified" according to the results of these tests and the seroclassification was compared to other currently used classification systems: the World Health Organization operational classification, the bacilloscopic index and the Ridley-Jopling classification. When analysing the usefulness of these tests in the operational classification of PB and MB leprosy for treatment and follow-up purposes, the ML Flow test was the best point-of-care test for subjects in Nepal and despite the need for sample dilution, the ML ICA test yielded better performance among Brazilian subjects. Our results identified possible ways to improve the performance of both tests.


Subject(s)
Antigens, Bacterial/blood , Glycolipids/blood , Immunoglobulin Isotypes/blood , Leprosy/diagnosis , Mycobacterium leprae/immunology , Adolescent , Adult , Aged , Aged, 80 and over , Brazil , Case-Control Studies , Child , Child, Preschool , Chromatography, Affinity/methods , Female , Humans , Immunoassay/methods , Leprosy/immunology , Male , Middle Aged , Nepal , Predictive Value of Tests , Reagent Kits, Diagnostic , Sensitivity and Specificity , Young Adult
9.
Mem Inst Oswaldo Cruz ; 107 Suppl 1: 197-208, 2012 Dec.
Article in English | MEDLINE | ID: mdl-23283472

ABSTRACT

A variety of host immunogenetic factors appear to influence both an individual's susceptibility to infection with Mycobacterium leprae and the pathologic course of the disease. Animal models can contribute to a better understanding of the role of immunogenetics in leprosy through comparative studies helping to confirm the significance of various identified traits and in deciphering the underlying mechanisms that may be involved in expression of different disease related phenotypes. Genetically engineered mice, with specific immune or biochemical pathway defects, are particularly useful for investigating granuloma formation and resistance to infection and are shedding new light on borderline areas of the leprosy spectrum which are clinically unstable and have a tendency toward immunological complications. Though armadillos are less developed in this regard, these animals are the only other natural hosts of M. leprae and they present a unique opportunity for comparative study of genetic markers and mechanisms associable with disease susceptibility or resistance, especially the neurological aspects of leprosy. In this paper, we review the recent contributions of genetically engineered mice and armadillos toward our understanding of the immunogenetics of leprosy.


Subject(s)
Animals, Genetically Modified , Armadillos/genetics , Disease Models, Animal , Immunogenetic Phenomena/immunology , Leprosy/genetics , Leprosy/immunology , Mice/genetics , Mycobacterium leprae , Animals , Armadillos/microbiology , Mice/immunology , Mycobacterium leprae/genetics , Mycobacterium leprae/immunology
10.
s.l; s.n; 2002. 14 p. ilus, tab.
Non-conventional in English | Sec. Est. Saúde SP, HANSEN, Hanseníase Leprosy, SESSP-ILSLACERVO, Sec. Est. Saúde SP | ID: biblio-1241013

ABSTRACT

Millions of patients with leprosy suffer from nerve damage resulting in disabilities as a consequence of Mycobacterium leprae infection. However, mechanisms of nerve damage have not been elucidated because of the lack of a model that maintains M. leprae viability and mimics disease conditions. A model was developed using viable M. leprae, rat Schwann cells, and Schwann cell-neuron cocultures incubated at 33 degrees C. M. leprae retained 56 per cente viability in Schwann cells for 3 weeks after infection at 33 degrees C, compared with 3.6 per cente viability at 37 degrees C. Infected Schwann cells had altered morphology and expression of genes encoding cellular adhesion molecules at 33 degrees C but were capable of interacting with and myelinating neurons. Cocultures, infected after myelination occurred, showed no morphological changes in myelin architecture after 1 month of incubation at 33 degrees C, and M. leprae retained 53 per cente viability. This article describes a new model for studying the effects of M. leprae on Schwann cells.


Subject(s)
Humans , Animals , Mice , Rats , Mice, Nude , Cell Communication/physiology , Cells, Cultured , Schwann Cells/physiology , Schwann Cells/microbiology , Schwann Cells/pathology , Schwann Cells/ultrastructure , Leprosy/microbiology , Leprosy/pathology , Microscopy, Electron, Scanning , Models, Neurological , Mycobacterium leprae/growth & development , Mycobacterium leprae/physiology , Neurons/physiology , Neurons/microbiology , Neurons/pathology
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