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1.
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
2.
PLoS Negl Trop Dis ; 14(5): e0008325, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-32453754

RESUMO

Leprosy urgently needs a precise and early diagnostic tool. The sensitivity of the direct (bacilli staining, Mycobacterium leprae DNA) and indirect (antibody levels, T cell assays) diagnostics methods vary based on the clinical form. Recently, PCR-based M. leprae DNA detection has been shown to differentially diagnose leprosy from other dermatological conditions. However, accuracy can still be improved, especially for use with less invasive clinical samples. We tested different commercial DNA extraction kits: DNeasy Blood & Tissue, QIAamp DNA Microbiome, Maxwell 16 DNA Purification, PowerSoil DNA Isolation; as well as in-house phenol-chloroform and Trizol/FastPrep methods. Extraction was performed on M. leprae-infected mouse footpads and different clinical samples of leprosy patients (skin biopsies and scrapings, lesion, oral and nasal swabs, body hair, blood on FTA cards, peripheral whole blood). We observed that the Microbiome kit was able to enrich for mycobacterial DNA, most likely due the enzymatic digestion cocktail along with mechanical disruption involved in this method. Consequently, we had a significant increase in sensitivity in skin biopsies from paucibacillary leprosy patients using a duplex qPCR targeting 16S rRNA (M. leprae) and 18S rRNA (mammal) in the StepOnePlus system. Our data showed that the presence of M. leprae DNA was best detected in skin biopsies and skin scrapings, independent of the extraction method or the clinical form. For multibacillary patients, detection of M. leprae DNA in nasal swabs indicates the possibility of having a much less invasive sample that can be used for the purposes of DNA sequencing for relapse analysis and drug resistance monitoring. Overall, DNA extracted with the Microbiome kit presented the best bacilli detection rate for paucibacillary cases, indicating that investments in extraction methods with mechanical and DNA digestion should be made.


Assuntos
DNA Bacteriano/isolamento & purificação , Mycobacterium leprae/isolamento & purificação , Reação em Cadeia da Polimerase/métodos , Animais , DNA Bacteriano/genética , Humanos , Camundongos , Mycobacterium leprae/genética , RNA Bacteriano/genética , RNA Ribossômico 16S/genética , Sensibilidade e Especificidade
3.
Klin Lab Diagn ; 65(5): 289-293, 2020.
Artigo em Russo | MEDLINE | ID: mdl-32298544

RESUMO

The glycoconjugates with BSA (bovine serum albumin) were synthesized using a next saccharide: disaccharide derivative M.leprae PGL-1 (phenolic glycolipid-1); a complex of the disaccharide fragment and the branched hexasaccharide fragment LAM (lipoarabinomannan); diarabinofuranose fragment LAM. These glycoconjugates were used as antigenic components for leprosy rapid serotest construction in immunochromatographic format (leprosy LF serotest). The data obtained with sera of leprosy patients, patients who have been in contact with leprosy, and healthy donors indicate that the most promising antigenic component is a BSA conjugate with two synthetic epitopes - a disaccharide derivative of PGL-1 and a branched hexasaccharide fragment of LAM. The leprosy LF serotest with such glycoconjugate demonstrated the greatest diagnostic sensitivity for main forms of leprosy - paucibacillary (PB) and multibacillary (MB).


Assuntos
Antígenos de Bactérias/imunologia , Glicoconjugados/química , Glicolipídeos/imunologia , Hanseníase/diagnóstico , Anticorpos Antibacterianos , Ensaio de Imunoadsorção Enzimática , Humanos , Imunoensaio , Hanseníase/sangue , Lipopolissacarídeos/química , Mycobacterium leprae , Testes Sorológicos
4.
PLoS Negl Trop Dis ; 14(4): e0008276, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-32339201

RESUMO

Leprosy is a chronic infectious disease caused by Mycobacterium leprae (M. leprae) and the more recently discovered Mycobacterium lepromatosis (M. lepromatosis). The two leprosy bacilli cause similar pathologic conditions. They primarily target the skin and the peripheral nervous system. Currently it is considered a Neglected Tropical Disease, being endemic in specific locations within countries of the Americas, Asia, and Africa, while in Europe it is only rarely reported. The reason for a spatial inequality in the prevalence of leprosy in so-called endemic pockets within a country is still largely unexplained. A systematic review was conducted targeting leprosy transmission research data, using PubMed and Scopus as sources. Publications between January 1, 1945 and July 1, 2019 were included. The transmission pathways of M. leprae are not fully understood. Solid evidence exists of an increased risk for individuals living in close contact with leprosy patients, most likely through infectious aerosols, created by coughing and sneezing, but possibly also through direct contact. However, this systematic review underscores that human-to-human transmission is not the only way leprosy can be acquired. The transmission of this disease is probably much more complicated than was thought before. In the Americas, the nine-banded armadillo (Dasypus novemcinctus) has been established as another natural host and reservoir of M. leprae. Anthroponotic and zoonotic transmission have both been proposed as modes of contracting the disease, based on data showing identical M. leprae strains shared between humans and armadillos. More recently, in red squirrels (Sciurus vulgaris) with leprosy-like lesions in the British Isles M. leprae and M. lepromatosis DNA was detected. This finding was unexpected, because leprosy is considered a disease of humans (with the exception of the armadillo), and because it was thought that leprosy (and M. leprae) had disappeared from the United Kingdom. Furthermore, animals can be affected by other leprosy-like diseases, caused by pathogens phylogenetically closely related to M. leprae. These mycobacteria have been proposed to be grouped as a M. leprae-complex. We argue that insights from the transmission and reservoirs of members of the M. leprae-complex might be relevant for leprosy research. A better understanding of possible animal or environmental reservoirs is needed, because transmission from such reservoirs may partly explain the steady global incidence of leprosy despite effective and widespread multidrug therapy. A reduction in transmission cannot be expected to be accomplished by actions or interventions from the human healthcare domain alone, as the mechanisms involved are complex. Therefore, to increase our understanding of the intricate picture of leprosy transmission, we propose a One Health transdisciplinary research approach.


Assuntos
Reservatórios de Doenças , Transmissão de Doença Infecciosa , Hanseníase/transmissão , Hanseníase/veterinária , Animais , Tatus/microbiologia , Saúde Global , Humanos , Incidência , Hanseníase/epidemiologia , Mycobacterium/isolamento & purificação , Mycobacterium leprae/isolamento & purificação , Prevalência , Sciuridae/microbiologia
5.
PLoS Negl Trop Dis ; 14(4): e0007534, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-32240160

RESUMO

BACKGROUND: Deposition of complement factors on Mycobacterium leprae may enhance phagocytosis. Such deposition may occur through the lectin pathway of complement. Three proteins of the lectin pathway are produced from the gene MASP1: Mannan-binding lectin-associated serine protease 1 (MASP-1) and MASP-3 and mannan-binding lectin-associated protein of 44 kDa (MAp44). Despite their obvious importance, the roles played by these proteins have never been investigated in leprosy disease. METHODOLOGY: We haplotyped five MASP1 polymorphisms by multiplex sequence-specific PCR (intronic rs7609662*G>A and rs13064994*C>T, exon 12 3'-untranslated rs72549262*C>G, rs1109452*C>T and rs850314*G>A) and measured MASP-1, MASP-3 and MAp44 serum levels in 196 leprosy patients (60%, lepromatous) and 193 controls. PRINCIPAL FINDINGS: Lower MASP-3 and MAp44 levels were observed in patients, compared with controls (P = 0.0002 and P<0.0001, respectively) and in lepromatous, compared with non-lepromatous patients (P = 0.008 and P = 0.002, respectively). Higher MASP-3 levels were present in controls carrying variants/haplotypes associated with leprosy resistance (rs13064994*T, rs1109452_rs850314*CG within GT_CCG and rs850314*A: OR = 0.5-0.6, Pcorr = 0.01-0.04). Controls with rs1109452*T, included in susceptibility haplotypes (GT_GTG/GT_CTG: OR = 2.0, Pcorr = 0.03), had higher MASP-1 and lower MASP-3 levels (P≤0.009). Those with GC_CCG, presented increasing susceptibility (OR = 1.7, Pcorr = 0.006) and higher MAp44 levels (P = 0.015). MASP-3 expression decreased in patients, compared with controls carrying rs1109452_rs850314*CA or CG (P≤0.02), which may rely on exon 12 CpG methylation and/or miR-2861/miR-3181 mRNA binding. CONCLUSION: Polymorphisms regulating MASP-3/MAp44 availability in serum modulate leprosy susceptibility, underlining the importance of lectin pathway regulation against pathogens that exploit phagocytosis to parasitize host macrophages.


Assuntos
Predisposição Genética para Doença , Hanseníase/genética , Hanseníase/patologia , Serina Proteases Associadas a Proteína de Ligação a Manose/análise , Serina Proteases Associadas a Proteína de Ligação a Manose/genética , Mycobacterium leprae/imunologia , Polimorfismo de Nucleotídeo Único , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Estudos de Casos e Controles , Estudos Transversais , Feminino , Haplótipos , Humanos , Masculino , Pessoa de Meia-Idade , Adulto Jovem
6.
PLoS Negl Trop Dis ; 14(3): e0008127, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-32203502

RESUMO

Understanding the prevalence of M. leprae infection in armadillos is important because of evidence from Brazil and other countries of an association between contact with armadillos and the development of Hansen's Disease (leprosy). Our aim was to characterize studies which have investigated natural M. leprae infection in wild armadillos in Brazil, and to quantify and explore variability in the reported prevalence of infection. We conducted a systematic review (PROSPERO CRD42019155277) of publications in MEDLINE, EMBASE, Global Health, Scopus, LILACS, Biblioteca Digital Brasileira de Teses e Dissertações, Catálogo de Teses e Dissertações de CAPES, and Biblioteca Virtual em Saúde up to 10/2019 using Mesh and text search terms (in English, Portuguese, Spanish, and French). The 10 included studies represented a total sample of 302 armadillos comprising 207 (69%) Dasypus novemcinctus, 67 (22%) Euphractus sexcinctus, 16 (5%) Priodontes maximus, 10 (3%) Cabassous unicinctus, and 2 (1%) Cabassous tatouay from 7 different states. Methods used included histopathology (4 studies), PGL-1 and LID-1 antigen detection (4 studies) and examination for clinical signs of disease (4 studies). Eight studies used PCR of which 7 targeted the RLEP repetitive element and 3 tested for inhibitory substances. M. leprae prevalence by PCR ranged from 0% (in 3 studies) to 100% in one study, with a summary estimate of 9.4% (95% CI 0.4% to 73.1%) and a predictive interval of 0-100%. The average prevalence is equivalent to 1 in 10 armadillos in Brazil being infected with M. leprae, but wide variation in sample estimates means that the prevalence in any similar study would be entirely unpredictable. We propose instead that future studies aim to investigate transmission and persistence of M. leprae within and between armadillo populations, meanwhile adopting the precautionary principle to protect human health and an endangered species in Brazil.


Assuntos
Tatus/microbiologia , Hanseníase/epidemiologia , Hanseníase/veterinária , Mycobacterium leprae/isolamento & purificação , Animais , Animais Selvagens/microbiologia , Brasil/epidemiologia , DNA Bacteriano/análise , Bases de Dados Factuais , Mapeamento Geográfico , Mycobacterium leprae/genética , Reação em Cadeia da Polimerase , Prevalência , Sequências Repetitivas de Ácido Nucleico , Zoonoses/epidemiologia , Zoonoses/microbiologia
7.
Mem Inst Oswaldo Cruz ; 115: e190324, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32130367

RESUMO

BACKGROUND: Leprosy is an infectious-contagious disease caused by Mycobacterium leprae that remain endemic in 105 countries. This neglected disease has a wide range of clinical and histopathological manifestations that are related to the host inflammatory and immune responses. More recently, the inflammasome has assumed a relevant role in the inflammatory response against microbiological agents. However, the involvement of inflammasome in leprosy remains poorly understood. OBJECTIVES: The aim is to associate biomarkers of inflammasome with the different immunopathological forms of leprosy. METHODS: We performed an observational, cross-sectional, and comparative study of the immunophenotypic expression of inflammasome-associated proteins in immunopathological forms of leprosy of 99 skin lesion samples by immunohistochemistry. The intensity and percentage of NLRP3, Caspase-1, Caspases-4/5, interleukin-1ß and interleukin-18 immunoreactivities in the inflammatory infiltrate of skin biopsies were evaluated. FINDINGS: Strong expression of NLRP3 and inflammatory Caspases-4/5 were observed in lepromatous leprosy (lepromatous pole). In addition, were observed low expression of caspase-1, interleukin-1ß, and interleukin-18 in tuberculoid and lepromatous leprosy. The interpolar or borderline form showed immunophenotype predominantly similar to the lepromatous pole. MAIN CONCLUSIONS: Our results demonstrate that the NLRP3 inflammasome is inactive in leprosy, suggesting immune evasion of M. leprae.


Assuntos
Evasão da Resposta Imune/imunologia , Inflamassomos/metabolismo , Hanseníase/imunologia , Hanseníase/metabolismo , Mycobacterium leprae/imunologia , Proteína 3 que Contém Domínio de Pirina da Família NLR/metabolismo , Estudos Transversais , Humanos , Imuno-Histoquímica , Hanseníase/patologia
8.
Infect Dis Poverty ; 9(1): 19, 2020 Feb 13.
Artigo em Inglês | MEDLINE | ID: mdl-32051036

RESUMO

BACKGROUND: Mycobacterium leprae and Toxoplasma gondii infections are both neglected tropical diseases highly prevalent in Brazil. Infection with certain parasite species can significantly alter susceptibility to other important pathogens, and/or influence the development of pathology. Here we investigated the possible influence of M. leprae/T. gondii co-parasitism on the manifestation of leprosy and its clinical forms. METHODS: Participants (n = 291) were recruited in Campos dos Goytacazes city, Rio de Janeiro state, southeast Brazil, from August 2015 to December 2019 and clinically diagnosed for leprosy. Participants were selected based on the presence (patients) or absence (healthy controls) of the leprosy disease. Contacts of patients were also recruited for this study. Serum samples from patients (n = 199) with leprosy, contacts (n = 40) and healthy controls (n = 52) were investigated for levels of IgM and IgG anti-phenolic glycolipid-1 (PGL-1) by ELISA. Additionally, IgG antibody against soluble Toxoplasma antigen (STAg) was measured in sera samples from leprosy patients, contacts and healthy controls for Toxoplasma gondii serology by ELISA. Anti-PGL-1 IgG and IgM levels were compared using one-way ANOVA Kruskal-Wallis or Mann-Whitney, while Spearman test was used to correlate levels of IgG anti-STAg and IgM/IgG anti-PGL-1 from seropositive and seronegative individuals for T. gondii infection. The risk of T. gondii infection for leprosy disease was assessed using Fisher's test. RESULTS: Levels of IgM anti-PGL-1 antibodies were significantly higher in multibacillary (MB) patients compared to paucibacillary (PB) patients (P = 0.0068). Higher IgM and IgG levels anti-PGL-1 were detected in patients with the lepromatous forms. The serologic prevalence for T. gondii infection was 74.9%. We detected increased anti-STAg antibody levels in leprosy patients (79.4%), reaching 88.8% within those with lepromatous form of this disease. The leprosy risk increase in T. gondii seropositive individuals was two-fold (odds ratio [OR] = 2.055; 95% confidence intervals [95% CI]: 1.18-3.51) higher than those seronegative, and considering the lepromatous leprosy risk this increase was even dramatic (OR = 4.33; 95% CI: 1.76-9.69) in T. gondii seropositive individuals. Moreover the leprosy risk in T. gondii seropositive individuals was weakly correlated to the levels of IgG anti-STAg and IgM/IgG anti-PGL-1. CONCLUSIONS: Altogether, our results suggest that T. gondii infection may exert immunomodulatory properties that influence to the susceptibility of leprosy, mainly on its more severe clinical form. A better understanding of parasite immunomodulation can ultimately contribute to the development of medical applications.


Assuntos
Anticorpos Antibacterianos/sangue , Hanseníase Virchowiana/epidemiologia , Mycobacterium leprae/imunologia , Toxoplasma/imunologia , Toxoplasmose/epidemiologia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Brasil/epidemiologia , Estudos de Casos e Controles , Criança , Comorbidade , Ensaio de Imunoadsorção Enzimática , Feminino , Glicolipídeos/imunologia , Humanos , Imunoglobulina G/imunologia , Imunoglobulina M/imunologia , Masculino , Pessoa de Meia-Idade , Estudos Soroepidemiológicos , Adulto Jovem
9.
Am J Trop Med Hyg ; 102(4): 724-727, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-32043454

RESUMO

The ongoing transmission of leprosy in India is worrisome, and emerging drug resistance may be one of the factors responsible for the continued transmission of leprosy in India. Emerging cases of multidrug-resistant Mycobacterium leprae pose a great threat to eradication of leprosy and must be addressed with utmost priority. We report a case of multidrug-resistant M. leprae in a case of relapse where slit skin smear (SSS) was negative and histopathology was inconclusive. Drug resistance studies in leprosy are undertaken only in smear-positive relapse cases, and detection of this type of multidrug resistance in a case with negative SSS and innocuous histopathology is rather unusual and highlights the importance of undertaking drug resistance tests even in smear-negative cases of leprosy relapse. Resistance to ofloxacin (OFL) is also a cause for concern as OFL is one of the reserve drugs recommended for treatment of rifampicin-resistant strains.


Assuntos
Hansenostáticos/farmacologia , Hansenostáticos/uso terapêutico , Hanseníase/tratamento farmacológico , Hanseníase/microbiologia , Mycobacterium leprae/efeitos dos fármacos , Adulto , Farmacorresistência Bacteriana Múltipla , Humanos , Índia/epidemiologia , Hanseníase/epidemiologia , Masculino , Recidiva
10.
BMC Infect Dis ; 20(1): 62, 2020 Jan 20.
Artigo em Inglês | MEDLINE | ID: mdl-31959113

RESUMO

BACKGROUND: To evaluate the effectiveness and safety of the World Health Organization antibiotic regimen for the treatment of paucibacillary (PB) and multibacillary (MB) leprosy compared to other available regimens. METHODS: We performed a search from 1982 to July 2018 without language restriction. We included randomized controlled trials, quasi-randomized trials, and comparative observational studies (cohorts and case-control studies) that enrolled patients of any age with PB or MB leprosy that were treated with any of the leprosy antibiotic regimens established by the WHO in 1982 and used any other antimicrobial regimen as a controller. Primary efficacy outcomes included: complete clinical cure, clinical improvement of the lesions, relapse rate, treatment failure. Data were pooled using a random effects model to estimate the treatment effects reported as relative risk (RR) with 95% confidence intervals (CI). RESULTS: We found 25 eligible studies, 11 evaluated patients with paucibacillary leprosy, while 13 evaluated patients with MB leprosy and 1 evaluated patients of both groups. Diverse regimen treatments and outcomes were studied. Complete cure at 6 months of multidrug therapy (MDT) in comparison to rifampin-ofloxacin-minocycline (ROM) found RR of 1.06 (95% CI 0.88-1.27) in five studies. Whereas six studies compare the same outcome at different follow up periods between 6 months and 5 years, according to the analysis ROM was not better than MDT (RR of 1.01 (95% CI 0.78-1.31)) in PB leprosy. CONCLUSION: Not better treatment than the implemented by the WHO was found. Diverse outcome and treatment regimens were studied, more statements to standardized the measurements of outcomes are needed.


Assuntos
Hansenostáticos/uso terapêutico , Hanseníase Multibacilar/tratamento farmacológico , Hanseníase Paucibacilar/tratamento farmacológico , Minociclina/uso terapêutico , Ofloxacino/uso terapêutico , Rifampina/uso terapêutico , Organização Mundial da Saúde , Adolescente , Adulto , Idoso , Criança , Protocolos Clínicos , Quimioterapia Combinada/efeitos adversos , Feminino , Humanos , Hansenostáticos/efeitos adversos , Masculino , Pessoa de Meia-Idade , Minociclina/efeitos adversos , Mycobacterium leprae/efeitos dos fármacos , Mycobacterium leprae/isolamento & purificação , Doenças Negligenciadas/tratamento farmacológico , Ofloxacino/efeitos adversos , Recidiva , Rifampina/efeitos adversos , Falha de Tratamento , Adulto Jovem
11.
Am J Trop Med Hyg ; 102(3): 547-552, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-31933458

RESUMO

Resistance to anti-leprosy drugs is on the rise. Several studies have documented resistance to rifampicin, dapsone, and ofloxacin in patients with leprosy. We looked for point mutations within the folP1, rpoB, and gyrA gene regions of the Mycobacterium leprae genome predominantly in the neural form of leprosy. DNA samples from 77 nerve tissue samples were polymerase chain reaction (PCR)-amplified for M leprae DNA and sequenced for drug resistance-determining regions of genes rpoB, folP1, and gyrA. The mean age at presentation and onset was 38.2 ± 13.4 (range 14-71) years and 34.9 ± 12.6 years (range 10-63) years, respectively. The majority had borderline tuberculoid leprosy (53 [68.8%]). Mutations associated with resistance were identified in 6/77 (7.8%) specimens. Mutations seen were those associated with resistance to rifampicin, ofloxacin, and dapsone. All the six patients were drug-naive. The clinical and pathological manifestations in this group did not differ from the drug-sensitive group. This study highlights the occurrence of resistance to the standard multidrug therapy and ofloxacin in leprosy. Among the entire cohort, 1/77 (1.3%) showed resistance to rifampicin, 2/77 (2.6%) to dapsone, and 5/77 (6.4%) to ofloxacin. Six new patients showing infection by mutant strains indicated the emergence of primary resistance. Resistance to ofloxacin could be due to frequent use of quinolones for many bacterial infections. The results of the study indicate the need for development of a robust and strict surveillance system for detecting drug resistance in leprosy in India.


Assuntos
Hansenostáticos/uso terapêutico , Hanseníase/tratamento farmacológico , Hanseníase/microbiologia , Mycobacterium leprae/efeitos dos fármacos , Adolescente , Adulto , Idoso , Criança , Pré-Escolar , Estudos de Coortes , Estudos Transversais , Farmacorresistência Bacteriana , Quimioterapia Combinada , Feminino , Humanos , Índia/epidemiologia , Lactente , Hansenostáticos/farmacologia , Hanseníase/epidemiologia , Masculino , Testes de Sensibilidade Microbiana , Pessoa de Meia-Idade , Mutação , Mycobacterium leprae/genética , Adulto Jovem
12.
Sci Rep ; 10(1): 1284, 2020 Jan 28.
Artigo em Inglês | MEDLINE | ID: mdl-31992776

RESUMO

Host genetic susceptibility to leprosy has been intensively investigated over the last decades; however, there are no studies on the role of genetic variants in disease recurrence. A previous initiative identified three recurrent cases of leprosy for which none of the M. leprae strains, as obtained in the first and the second diagnosis, had any known genomic variants associated to resistance to Multidrug therapy; in addition, whole genome sequencing indicated that the same M. leprae was causing two out of the three recurrences. Thus, these individuals were suspected of being particularly susceptible to M. leprae infection, either as relapse or reinfection. To verify this hypothesis, 19 genetic markers distributed across 11 loci (14 genes) classically associated with leprosy were genotyped in the recurrent and in three matching non-recurrent leprosy cases. An enrichment of risk alleles was observed in the recurrent cases, suggesting the existence of a particularly high susceptibility genetic profile among leprosy patients predisposing to disease recurrence.


Assuntos
Loci Gênicos , Predisposição Genética para Doença , Hanseníase/genética , Mycobacterium leprae , Polimorfismo de Nucleotídeo Único , Sequenciamento Completo do Genoma , Feminino , Humanos , Masculino , Recidiva
13.
s.l; s.n; 2020. 8 p. graf.
Não convencional em Inglês | Sec. Est. Saúde SP, HANSEN, SESSP-ILSLPROD, Sec. Est. Saúde SP, SESSP-ILSLACERVO, Sec. Est. Saúde 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
14.
s.l; s.n; 2020. 23 p. ilus, tab, graf.
Não convencional em Inglês | Sec. Est. Saúde SP, HANSEN, SESSP-ILSLPROD, Sec. Est. Saúde SP, SESSP-ILSLACERVO, Sec. Est. Saúde 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
15.
BMC Infect Dis ; 19(1): 1013, 2019 Nov 29.
Artigo em Inglês | MEDLINE | ID: mdl-31783808

RESUMO

BACKGROUND: Leprosy is a chronic granulomatous infection caused by Mycobacterium leprae. It is a polymorphic disease with a wide range of cutaneous and neural manifestations. Ulcer is not a common feature in leprosy patients, except during reactional states, Lucio's phenomenon (LP), or secondary to neuropathies. CASES PRESENTATION: We report eight patients with multibacillary leprosy who presented specific skin ulcers as part of their main leprosy manifestation. Ulcers were mostly present on lower limbs (eight patients), followed by the upper limbs (three patients), and the abdomen (one patient). Mean time from onset of skin ulcers to diagnosis of leprosy was 17.4 months: all patients were either misdiagnosed or had delayed diagnosis, with seven of them presenting grade 2 disability by the time of the diagnosis. Reactional states, LP or neuropathy as potential causes of ulcers were ruled out. Biopsy of the ulcer was available in seven patients: histopathology showed mild to moderate lympho-histiocytic infiltrate with vacuolized histiocytes and intact isolated and grouped acid-fast bacilli. Eosinophils, vasculitis, vasculopathy or signs of chronic venous insufficiency were not observed. Skin lesions improved rapidly after multidrug therapy, without any concomitant specific treatment for ulcers. CONCLUSIONS: This series of cases highlights the importance of recognizing ulcers as a specific cutaneous manifestation of leprosy, allowing diagnosis and treatment of the disease, and therefore avoiding development of disabilities and persistence of the transmission chain of M. leprae.


Assuntos
Hanseníase Multibacilar/diagnóstico , Úlcera Cutânea/diagnóstico , Adolescente , Adulto , Idoso , Erros de Diagnóstico , Humanos , Hansenostáticos , Hanseníase Multibacilar/complicações , Masculino , Pessoa de Meia-Idade , Mycobacterium leprae/isolamento & purificação , Pele/patologia , Úlcera Cutânea/complicações
16.
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
17.
PLoS Negl Trop Dis ; 13(12): e0007946, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31881061

RESUMO

BACKGROUND: Although leprosy is efficiently treated by multidrug therapy, resistance to first-line (dapsone, rifampin) and second-line (fluoroquinolones) drugs has been described worldwide. However, the characteristics of drug resistance in Southwest China remain unknown. Furthermore, the sensitivity of polymerase chain reaction (PCR)/sequencing for resistance detection is limited, especially for paucibacillary (PB) leprosy patients. The current study aimed to develop a nested PCR/sequencing and TaqMan SNP Genotyping Assay to increase the sensitivity of the method used to detect drug resistance in Mycobacterium leprae and to reveal the nature of M. leprae drug resistance in Southwest China. METHODOLOGY/PRINCIPAL FINDINGS: Seventy-six specimens, including skin biopsy (n = 64), formalin-fixed paraffin-embedded (FFPE) (n = 11) and skin-slit smear (SSS) (n = 1) samples from multibacillary (MB, n = 70) and PB (n = 6) leprosy patients from Southwest China, were included in this study. The presence of mutations in drug resistance-determining regions (DRDRs) of the rpoB, folP1, and gyrA genes, which are associated with rifampicin, dapsone, and quinolone resistance, respectively, was detected by PCR/sequencing, as recommended by the WHO, and the nested PCR and TaqMan SNP Genotyping Assay developed in this study. Mutations in the folP gene were detected in 19 (25.00%) samples, indicating dapsone-resistant M. leprae, with one (1.31%) sample showing mutations in two genes, folP and gyrA, reflecting multidrug-resistant strains to dapsone and ofloxacin. However, no rpoB mutation was detected. Compared with PCR/sequencing, nested PCR increased the sensitivity of detecting rpoB (from 51.39% to 78.94% for leprosy patients and from 0.00% to 50.00% for PB), gyrA (from 75.00% to 80.26% for leprosy patients and from 50.00% to 66.67% for PB), and folP1 (from 5.26% to 84.21% for leprosy patients and from 0.00% to 66.67% for PB). Moreover, the TaqMan SNP Genotyping Assay showed greater sensitivity for folP1 detection (from 5.26% to 78.94-86.84% for leprosy patients and from 0.00% to 33.33%-83.33% for PB patients) than the PCR/sequencing method. In addition, the latter method was able to more easily distinguish heterozygous genotypes and mutant homozygous genotypes from homozygous genotypes. CONCLUSIONS/SIGNIFICANCE: Nested PCR/sequencing and the TaqMan SNP Genotyping Assay are rapid and highly sensitive methods for detecting drug resistance in leprosy cases. The current study revealed that diamino-diphenylsulfone (DDS; also known as dapsone) resistance in M. leprae, as indicated by folP1 gene detection, is still the most concerning form of drug resistance in leprosy patients from Southwest China.


Assuntos
Farmacorresistência Bacteriana , Técnicas de Genotipagem/métodos , Hanseníase/microbiologia , Testes de Sensibilidade Microbiana/métodos , Mycobacterium leprae/efeitos dos fármacos , Mycobacterium leprae/genética , Reação em Cadeia da Polimerase/métodos , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , China , Feminino , Genes Bacterianos , Genótipo , Humanos , Masculino , Pessoa de Meia-Idade , Mycobacterium leprae/isolamento & purificação , Sensibilidade e Especificidade , Análise de Sequência de DNA/métodos , Adulto Jovem
18.
MSMR ; 26(12): 2-6, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31860322

RESUMO

Leprosy, or Hansen's disease (HD), is caused by the bacterium Mycobacterium leprae and is a significant cause of morbidity worldwide. Clinical manifestations range from isolated skin rash to severe peripheral neuropathy. Treatment involves a prolonged course of multiple antimicrobials. Although rare in the U.S., with only 168 new cases reported in 2016, HD remains a prevalent disease throughout the world, with 214,783 new cases worldwide that same year.1 It remains clinically relevant for service members born in and deployed to endemic regions. This report describes a case of HD diagnosed in an active duty soldier born and raised in Micronesia, a highly endemic region.


Assuntos
Hanseníase/patologia , Militares/estatística & dados numéricos , Mycobacterium leprae , Doenças Profissionais/patologia , Úlcera Cutânea/patologia , Humanos , Hanseníase/epidemiologia , Hanseníase/microbiologia , Masculino , Micronésia/epidemiologia , Doenças Profissionais/epidemiologia , Doenças Profissionais/microbiologia , Úlcera Cutânea/microbiologia , Estados Unidos/epidemiologia , Adulto Jovem
19.
Emerg Microbes Infect ; 8(1): 1479-1489, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31621517

RESUMO

Reports on antimicrobial resistance (AMR) of Mycobacterium leprae, relationship with bacteriological index (BI), and transmission in China are limited. We investigated the emergence of AMR mutations, the relationship between BI and AMR in complete, moderate and lack of BI decline cases, and molecular epidemiological features of AMR cases by enrolling 290 leprosy cases from four endemic provinces. Seven (2.41%), one (0.34%), five (1.72%), one (0.34%), and one (0.34%) strains had single mutations in folP1, rpoC, gyrA, gyrB, and 23S rRNA, respectively. Double mutations in folP1 and gyrA, rpoB and gyrA, and gyrA and 23S rRNA were observed in one (0.34%) strain each. Mutated strains occurred in three out of 81 (95% CI-0.005-0.079, p = 0.083) cases with complete BI decline, in seven out of 103 (95% CI 0.018-0.117, p = 0.008) cases with moderate BI decline, and in four out of 34 (95% CI 0.003-0.231, p = 0.044) cases with lack of BI decline. Most of these mutated strains were geographically separated and diverged genotypically. AMR mutations may not be the main cause of the lack of BI decline. The low transmission of AMR strains at the county level indicates an ongoing transmission at close contact levels.


Assuntos
Farmacorresistência Bacteriana , Hansenostáticos/farmacologia , Hanseníase/microbiologia , Mycobacterium leprae/efeitos dos fármacos , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , China/epidemiologia , Feminino , Humanos , Hanseníase/epidemiologia , Masculino , Testes de Sensibilidade Microbiana , Pessoa de Meia-Idade , Mutação , Mycobacterium leprae/classificação , Mycobacterium leprae/genética , Mycobacterium leprae/isolamento & purificação , Filogenia , Adulto Jovem
20.
PLoS Negl Trop Dis ; 13(10): e0007731, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31577795

RESUMO

BACKGROUND: Detection and pathology analysis of Mycobacterium leprae using skin biopsy tissues are essential for leprosy diagnosis and monitoring response to treatment. Although formalin fixation of patient tissues may not be ideal for molecular studies, biopsy samples are the most accessible material from suspected cases. Therefore, clinical molecular laboratories must be able to utilize formalin-fixed, paraffin-embedded (FFPE) material. OBJECTIVE: To determine the best molecular method for diagnosing and monitoring leprosy in FFPE specimens, we developed a single-tube nested PCR (STNPCR) (131 bp) and SYBRGreen PCR (101 bp) assay using primers for the M. leprae-specific repetitive element (RLEP) gene and evaluated the results compared to those using previously established RLEP primers (372 bp). METHODS: FFPE biopsy samples obtained from 145 leprosy patients (during or after multidrug therapy (MDT)) and patients with 29 other confounding dermatoses were examined by the bacteria index (BI) and by simple PCR, STNPCR, and SYBRGreen PCR using primers amplifying a 372-bp, 131-bp or 101-bp fragment of RLEP, respectively. RESULTS: In leprosy patients receiving MDT, STNPCR showed a highest specificity of 100% and a positive predictive value (PPV) of 100%. For multibacillary (MB), paucibacillary (PB) and all leprosy patients, the highest sensitivities were 91.42%, 39.13%, and 67.92%, negative predictive values (NPVs) were 8.57%, 60.36%, and 32.07%, and the highest accuracies were 93.93%, 62.67%, and 74.81%, respectively, higher than the results of SYBRGreen PCR and simple PCR. For post-MDT leprosy patients, SYBRGreen PCR showed the highest sensitivity of 50.0%, highest specificity of 100%, a PPV of 100%, an NPV of 100% and the highest accuracy of 83.72% for MB patients, which were higher than those of STNPCR and simple PCR. STNPCR showed the highest sensitivity of 26.66% and 34.48%, highest specificity of 100% and 100%, a PPV of 100% and 100%, NPV of 72.50% and 60.21%, and highest accuracy of 75.00% and 67.24% for PB and leprosy patients, respectively, higher than those of SYBRGreen PCR and simple PCR. CONCLUSIONS: These findings suggest that STNPCR or SYBRGreen PCR (131-bp and 101-bp fragment amplification, respectively) for RLEP using FFPE specimens performs better as a diagnostic test and for monitoring response to MDT than does simple PCR based on 372-bp fragment amplification. Additionally, STNPCR showed increased sensitivity for PB diagnosis using FFPE specimens, which can be transferred remotely or retrieved from previous leprosy patients.


Assuntos
Formaldeído , Hanseníase/diagnóstico , Mycobacterium leprae/isolamento & purificação , Inclusão em Parafina/métodos , Reação em Cadeia da Polimerase/métodos , Biópsia/métodos , China , Primers do DNA , DNA Bacteriano/genética , Quimioterapia Combinada , Humanos , Hansenostáticos/uso terapêutico , Hanseníase/tratamento farmacológico , Mycobacterium leprae/genética , Sequências Repetitivas de Ácido Nucleico/genética , Sensibilidade e Especificidade , Pele/microbiologia
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