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1.
PLoS Negl Trop Dis ; 14(4): e0007534, 2020 04.
Artículo en Inglés | MEDLINE | ID: mdl-32240160

RESUMEN

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.


Asunto(s)
Predisposición Genética a la Enfermedad , Lepra/genética , Lepra/patología , Serina Proteasas Asociadas a la Proteína de Unión a la Manosa/análisis , Serina Proteasas Asociadas a la Proteína de Unión a la Manosa/genética , Mycobacterium leprae/inmunología , Polimorfismo de Nucleótido Simple , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Estudios de Casos y Controles , Estudios Transversales , Femenino , Haplotipos , Humanos , Masculino , Persona de Mediana Edad , Adulto Joven
2.
Mem Inst Oswaldo Cruz ; 115: e190324, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32130367

RESUMEN

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.


Asunto(s)
Evasión Inmune/inmunología , Inflamasomas/metabolismo , Lepra/inmunología , Lepra/metabolismo , Mycobacterium leprae/inmunología , Proteína con Dominio Pirina 3 de la Familia NLR/metabolismo , Estudios Transversales , Humanos , Inmunohistoquímica , Lepra/patología
3.
Infect Dis Poverty ; 9(1): 19, 2020 Feb 13.
Artículo en Inglés | MEDLINE | ID: mdl-32051036

RESUMEN

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.


Asunto(s)
Anticuerpos Antibacterianos/sangre , Lepra Lepromatosa/epidemiología , Mycobacterium leprae/inmunología , Toxoplasma/inmunología , Toxoplasmosis/epidemiología , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Brasil/epidemiología , Estudios de Casos y Controles , Niño , Comorbilidad , Ensayo de Inmunoadsorción Enzimática , Femenino , Glucolípidos/inmunología , Humanos , Inmunoglobulina G/inmunología , Inmunoglobulina M/inmunología , Masculino , Persona de Mediana Edad , Estudios Seroepidemiológicos , Adulto Joven
4.
PLoS Negl Trop Dis ; 13(10): e0007764, 2019 10.
Artículo en Inglés | MEDLINE | ID: mdl-31600201

RESUMEN

Reversal reactions (RRs) in leprosy are characterized by a reduction in the number of bacilli in lesions associated with an increase in cell-mediated immunity against the intracellular bacterium Mycobacterium leprae, the causative pathogen of leprosy. To identify the mechanisms that contribute to cell-mediated immunity in leprosy, we measured changes in the whole blood-derived transcriptome of patients with leprosy before, during and after RR. We identified an 'RR signature' of 1017 genes that were upregulated at the time of the clinical diagnosis of RR. Using weighted gene correlated network analysis (WGCNA), we detected a module of 794 genes, bisque4, that was significantly correlated with RR, of which 434 genes were part of the RR signature. An enrichment for both IFN-γ and IFN-ß downstream gene pathways was present in the RR signature as well as the RR upregulated genes in the bisque4 module, including those encoding proteins of the guanylate binding protein (GBP) family that contributes to antimicrobial responses against mycobacteria. Specifically, GBP1, GBP2, GBP3 and GBP5 mRNAs were upregulated in the RR peripheral blood transcriptome, with GBP1, GBP2 and GBP5 mRNAs also upregulated in the RR disease lesion transcriptome. These data indicate that RRs involve a systemic upregulation of IFN-γ downstream genes including GBP family members as part of the host antimicrobial response against mycobacteria.


Asunto(s)
Proteínas de Unión al GTP/genética , Interferón gamma/inmunología , Lepra/inmunología , Lepra/metabolismo , Mapeo Cromosómico , Expresión Génica/efectos de los fármacos , Perfilación de la Expresión Génica , Humanos , Inmunidad Celular , Interferón beta , Mycobacterium leprae/inmunología , ARN Mensajero , Transcriptoma , Regulación hacia Arriba
5.
Biosens Bioelectron ; 145: 111698, 2019 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-31539652

RESUMEN

Mycobacterium leprae causes endemic disease leprosy which becomes chronic if not treated timely. To expedite this 'timely diagnosis', and that also at an early stage, here an attempt is made to fabricate an epitope-imprinted sensor. A molecularly imprinted polymer nanoparticles modified electrochemical quartz crystal microbalance sensor was developed for sensing of Mycobacterium leprae bacteria through its epitope sequence. Multiple monomers, 3-sulphopropyl methacrylate potassium salt, benzyl methacrylate and 4-aminothiophenol were utilized to imprint this bacterial epitope. Imprinted nanoparticles were electropolymerized on gold coated quartz electrode. The sensor was able to show specific binding towards the blood samples of infected patients, even in the presence of 'matrix' and other plasma proteins such as albumin and globulin. Even other peptide sequences, similar to epitope sequences only with two amino acid mismatches were also unable to show any binding. Sensor withstood analytical tests viz. selectivity, specificity, matrix effect, detection limit (0.161 nM), quantification limit (and 0.536 nM), reproducibility (RSD 2.01%). Hence a diagnostic tool for bacterium causing leprosy is successfully fabricated in a facile manner which will broaden the clinical access and efficient population screening can be made feasible.


Asunto(s)
Técnicas Biosensibles , Lepra/diagnóstico , Mycobacterium leprae/aislamiento & purificación , Tecnicas de Microbalanza del Cristal de Cuarzo , Epítopos/química , Epítopos/inmunología , Oro/química , Humanos , Lepra/microbiología , Impresión Molecular , Mycobacterium leprae/inmunología , Mycobacterium leprae/patogenicidad , Nanopartículas/química , Polímeros/química
6.
J Med Microbiol ; 68(11): 1629-1640, 2019 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-31553301

RESUMEN

Introduction. ML1899 is conserved in all mycobacterium sp. and is a middle member of mle-ML1898 operon involved in mycolic acid modification.Aim. In the present study attempts were made to characterize ML1899 in detail.Methodology. Bioinformatics tools were used for prediction of active-site residues, antigenic epitopes and a three-dimensional model of protein. The gene was cloned, expressed and purified as His-tagged protein in Escherichia coli for biophysical/biochemical characterization. Recombinant protein was used to treat THP-1 cells to study change in production of nitric oxide (NO), reactive oxygen species (ROS), cytokines and chemokines using flowcytometry/ELISA.Results. In silico analysis predicted ML1899 as a member of α/ß hydrolase family with GXSXG-motif and Ser126, His282, Asp254 as active-site residues that were confirmed by site-directed mutagensis. ML1899 exhibited esterase activity. It hydrolysed pNP-butyrate as optimum substrate at pH 8.0 and 50 °C with 5.56 µM-1 min-1 catalytic efficiency. The enzyme exhibited stability up to 60 °C temperature and between pH 6.0 to 9.0. K m, V max and specific activity of ML1899 were calculated to be 400 µM, 40 µmoles min-1 ml-1 and 27 U mg- 1, respectively. ML1899 also exhibited phospholipase activity. The protein affected the survival of macrophages when treated at higher concentration. ML1899 enhanced ROS/NO production and up-regulated pro-inflammatory cytokines and chemokine including TNF-α, IFN-γ, IL-6 and IL-8 in macrophages. ML1899 was also observed to elicit humoral response in 69 % of leprosy patients.Conclusion. These results suggested that ML1899, an esterase could up-regulate the immune responses in favour of macrophages at a low concentration but kills the THP-1 macrophages cells at a higher concentration.


Asunto(s)
Proteínas Bacterianas/inmunología , Esterasas/inmunología , Lepra/microbiología , Mycobacterium leprae/enzimología , Secuencia de Aminoácidos , Anticuerpos Antibacterianos/inmunología , Proteínas Bacterianas/química , Proteínas Bacterianas/genética , Citocinas/genética , Citocinas/inmunología , Estabilidad de Enzimas , Esterasas/química , Esterasas/genética , Femenino , Humanos , Concentración de Iones de Hidrógeno , Cinética , Lepra/inmunología , Macrófagos/inmunología , Macrófagos/microbiología , Masculino , Mycobacterium leprae/química , Mycobacterium leprae/genética , Mycobacterium leprae/inmunología , Óxido Nítrico/inmunología , Especies Reactivas de Oxígeno/inmunología , Alineación de Secuencia
7.
PLoS Negl Trop Dis ; 13(9): e0007368, 2019 09.
Artículo en Inglés | MEDLINE | ID: mdl-31504035

RESUMEN

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.


Asunto(s)
Trampas Extracelulares/inmunología , Inmunidad Innata , Lepra/inmunología , Adulto , Anciano , Anciano de 80 o más Años , Enfermedades Autoinmunes/inmunología , Enfermedades Autoinmunes/microbiología , Femenino , Humanos , Inflamación/inmunología , Inflamación/patología , Lepra/tratamiento farmacológico , Lepra/patología , Masculino , Persona de Mediana Edad , Mycobacterium leprae/inmunología , Mycobacterium leprae/patogenicidad , Neutrófilos/patología , Talidomida/administración & dosificación , Talidomida/uso terapéutico
8.
Microb Pathog ; 137: 103714, 2019 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-31493502

RESUMEN

Leprosy, once considered as poor man's disease may cause severe neurological complications and physical disabilities. Classification of leprosy depends upon the cell mediated and humoral immune responses of the host, from tuberculoid to lepromatous stage. Current therapy to prevent the disease is not only very lengthy but also consists of expensive multiple antibiotics in combination. Treatment and the duration depend on the bacillary loads, from six months in paucibacillary to a year in multibacillary leprosy. Although as per WHO recommendations, these antibiotics are freely available but still out of reach to patients of many rural areas of the world. In this review, we have focused on the nutritional aspect during the multi-drug therapy of leprosy along with the role of nutrition, particularly malnutrition, on susceptibility of Mycobacterium leprae and development of clinical symptoms. We further discussed the diet plan for the patients and how diet plans can affect the immune responses during the disease.


Asunto(s)
Dieta , Lepra/tratamiento farmacológico , Lepra/inmunología , Desnutrición , Antígenos Bacterianos/farmacología , Citocinas/metabolismo , Alimentos , Predisposición Genética a la Enfermedad , Humanos , Inmunidad , Inmunidad Humoral , Lepra/diagnóstico , Lepra/metabolismo , Masculino , Mycobacterium leprae/inmunología , Estado Nutricional , Factores de Riesgo , Selenio , Vitaminas , Zinc
9.
J Dermatol ; 46(10): 853-858, 2019 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-31432529

RESUMEN

In patients with lepromatous leprosy, Mycobacterium leprae is often observed inside the human microvascular endothelial cells (HMVEC) surrounding Schwann cells (SC) at the site of lesions in the peripheral nerves. Based on this observation, it is considered that the nasal mucous may be the invasion pathway for M. leprae and HMVEC serve as an important reservoir for the bacteria before they invade SC. In light of previous research which revealed that Mce1A protein mediates bacterial invasion into nasal epithelial cells and HMVEC, we conducted a study to determine whether the invasion of M. leprae into HMVEC can be suppressed by blocking the Mce1A protein. In this study, we analyzed bacterial invasive activity by adding recombinant Escherichia coli, which express the active region (InvX:72 a.a.) of Mce1A protein on their external membrane, into cultured HMVEC, using the adhesin involved in the diffuse adherence mechanism. The number of bacteria that invaded into the cells was then measured by a colony counting method. The active region of Mce1A was divided into four sections, and hyperimmune antisera was prepared for each section for analyzing the inhibitory effect against invasion. The invasive activity was suppressed by antibodies against InvX regions 1-24 a.a., 25-46 a.a. and 58-72 a.a. This suggests that the InvX regions 1-24 a.a., 25-46 a.a. and 58-72 a.a. of Mce1A protein play an important role in the invasion of M. leprae into HMVEC and that it may be possible to suppress entry of M. leprae in HMVEC with antibodies against these regions.


Asunto(s)
Anticuerpos Antibacterianos/inmunología , Proteínas Bacterianas/inmunología , Células Endoteliales/microbiología , Lepra/inmunología , Mycobacterium leprae/inmunología , Animales , Anticuerpos Antibacterianos/aislamiento & purificación , Proteínas Bacterianas/genética , Línea Celular , Recuento de Colonia Microbiana , Humanos , Sueros Inmunes/inmunología , Sueros Inmunes/aislamiento & purificación , Lepra/microbiología , Lepra/prevención & control , Mycobacterium leprae/patogenicidad , Conejos , Proteínas Recombinantes/genética , Proteínas Recombinantes/inmunología
10.
PLoS Negl Trop Dis ; 13(7): e0007589, 2019 07.
Artículo en Inglés | MEDLINE | ID: mdl-31344041

RESUMEN

The initial interaction between a microbial pathogen and the host immune response influences the outcome of the battle between the host and the foreign invader. Leprosy, caused by the obligate intracellular pathogen Mycobacterium leprae, provides a model to study relevant human immune responses. Previous studies have adopted a targeted approach to investigate host response to M. leprae infection, focusing on the induction of specific molecules and pathways. By measuring the host transcriptome triggered by M. leprae infection of human macrophages, we were able to detect a host gene signature 24-48 hours after infection characterized by specific innate immune pathways involving the cell fate mechanisms autophagy and apoptosis. The top upstream regulator in the M. leprae-induced gene signature was NUPR1, which is found in the M. leprae-induced cell fate pathways. The induction of NUPR1 by M. leprae was dependent on the production of the type I interferon (IFN), IFN-ß. Furthermore, NUPR1 mRNA and protein were upregulated in the skin lesions from patients with the multibacillary form of leprosy. Together, these data indicate that M. leprae induces a cell fate program which includes NUPR1 as part of the host response in the progressive form of leprosy.


Asunto(s)
Factores de Transcripción con Motivo Hélice-Asa-Hélice Básico/genética , Lepra/genética , Macrófagos/microbiología , Mycobacterium leprae/inmunología , Proteínas de Neoplasias/genética , Células Cultivadas , Perfilación de la Expresión Génica , Regulación de la Expresión Génica , Humanos , Interferón Tipo I/inmunología , Lepra/inmunología , Lepra/microbiología , Macrófagos/inmunología , Transducción de Señal
11.
Int J Mycobacteriol ; 8(2): 166-169, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31210160

RESUMEN

Background: Mycobacterium tuberculosis (M. tuberculosis) and Mycobacterium leprae (M. leprae) are morphologically, immunologically, and pathologically similar. The incidence of simultaneous tuberculosis (TB) and leprosy is still controversial. The aim of this study was to detect anti-phenolic glycolipid-I (anti-PGL-I) antibody in sera from TB patients at Dr. Hasan Sadikin Hospital Bandung, West Java, Indonesia. The aim of this study is to detect anti-phenolic glycolipid-I (anti-PGL-I) antibody in sera from TB patients at Dr. Hasan Sadikin Hospital Bandung, West Java, Indonesia. Methods: We performed a cross-sectional descriptive study with consecutive sampling from 112 TB patients clinically diagnosed by internist from the Internal Medicine Department and confirmed through bacteriological, histological, and chest radiograph examinations. The specimens were taken from the blood serum of the patient. Furthermore, the anti-PGL-I immunoglobulin (Ig) M and IgG serum level were evaluated using the enzyme-linked immunosorbent assay. Results: The mean of anti-PGL-I IgM and IgG serum levels in TB patients of this study was 34.17 ± 21.94 pg/ml and 41.44 ± 18.93 pg/ml with the mean of optical density values was 0.18 ± 0.05 and 0.26 ± 0.07. The seropositivity of anti-PGL-I in TB patients was 27.68% for IgM and 41.96% for IgG. The seropositivity of anti-PGL-I IgM and IgG level based on clinical manifestation of TB in this study from the highest to the lowest were as follows: extrapulmonary TB patients (61.29% and 59.57%), pulmonary TB patients (29.03% and 36.17%), and pulmonary with extrapulmonary TB patients (9.68% and 4.26%), respectively. Conclusion: The seropositivity of anti-PGL-I antibody in sera from TB patients in Bandung, West Java, Indonesia was 27.68% for IgM and 41.96% for IgG. Furthermore, periodic observations are needed to determine the likelihood of clinical manifestation of leprosy in TB patients.


Asunto(s)
Anticuerpos Antibacterianos/sangre , Antígenos Bacterianos/inmunología , Glucolípidos/inmunología , Inmunoglobulina G/sangre , Inmunoglobulina M/sangre , Lepra/diagnóstico , Tuberculosis/inmunología , Adolescente , Adulto , Anciano , Estudios Transversales , Ensayo de Inmunoadsorción Enzimática , Femenino , Humanos , Indonesia/epidemiología , Lepra/epidemiología , Lepra/inmunología , Masculino , Persona de Mediana Edad , Mycobacterium leprae/inmunología , Mycobacterium tuberculosis/inmunología , Tuberculosis/complicaciones , Tuberculosis/epidemiología , Adulto Joven
12.
BMC Infect Dis ; 19(1): 520, 2019 Jun 13.
Artículo en Inglés | MEDLINE | ID: mdl-31196008

RESUMEN

BACKGROUND: Leprosy is is still considered a public health issue and in Colombia 7-10% of new cases are found in children, indicating both active transmission and social inequality. We hypothesized that circulating antibodies against Natural Octyl Disaccharide-Leprosy IDRI Diagnostic (NDO-LID) (a combination of Mycobacterium leprae antigens) could reveal the social and environmental aspects associated with higher frequencies of M. leprae infection among children and adolescents in Colombia. METHODS: An observational cross-sectional study was conducted involving sampling from 82 children and adolescents (younger than 18 years of age) who had household contact with index leprosy patients diagnosed in the last 5 years. Data were analyzed through bivariate analysis made by applying a Pearson x2 test for qualitative variables, while quantitative variables, depending on their distribution, were analyzed using either a Student's t-test or Mann-Whitney U test. Multivariate analysis was performed using a multiple regression and binomial logistic approach. RESULTS: A bivariate analysis demonstrated that antibody titers against NDO-LID were significantly greater in children and adolescents with a low socioeconomic status that had: lived in vulnerable areas of the UAChR shared region; eaten armadillo meat; exposure of over 10 years to an index case and; not received BCG immunization. Moreover, a multivariate analysis showed that residing in the UAChR region has a strong association with a greater possibility of M. leprae infection. CONCLUSIONS: M. leprae transmission persists among young Colombians, and this is associated with social and environmental conditions. An intensification of efforts to identify new leprosy cases in vulnerable and forgotten populations where M. leprae transmission continues therefore appears necessary.


Asunto(s)
Lepra/diagnóstico , Mycobacterium leprae/aislamiento & purificación , Adolescente , Animales , Anticuerpos Antibacterianos/sangre , Armadillos , Vacuna BCG/inmunología , Niño , Preescolar , Colombia/epidemiología , Estudios Transversales , Ensayo de Inmunoadsorción Enzimática , Femenino , Humanos , Lactante , Lepra/epidemiología , Lepra/transmisión , Modelos Logísticos , Masculino , Carne/análisis , Carne/microbiología , Mycobacterium leprae/inmunología , Clase Social , Estadísticas no Paramétricas
13.
PLoS Negl Trop Dis ; 13(6): e0007400, 2019 06.
Artículo en Inglés | MEDLINE | ID: mdl-31181059

RESUMEN

BACKGROUND: Early detection of Mycobacterium leprae is a key strategy for disrupting the transmission chain of leprosy and preventing the potential onset of physical disabilities. Clinical diagnosis is essential, but some of the presented symptoms may go unnoticed, even by specialists. In areas of greater endemicity, serological and molecular tests have been performed and analyzed separately for the follow-up of household contacts, who are at high risk of developing the disease. The accuracy of these tests is still debated, and it is necessary to make them more reliable, especially for the identification of cases of leprosy between contacts. We proposed an integrated analysis of molecular and serological methods using artificial intelligence by the random forest (RF) algorithm to better diagnose and predict new cases of leprosy. METHODS: The study was developed in Governador Valadares, Brazil, a hyperendemic region for leprosy. A longitudinal study was performed, including new cases diagnosed in 2011 and their respective household contacts, who were followed in 2011, 2012, and 2016. All contacts were diligently evaluated by clinicians from Reference Center for Endemic Diseases (CREDEN-PES) before being classified as asymptomatic. Samples of slit skin smears (SSS) from the earlobe of the patients and household contacts were collected for quantitative polymerase chain reaction (qPCR) of 16S rRNA, and peripheral blood samples were collected for ELISA assays to detect LID-1 and ND-O-LID. RESULTS: The statistical analysis of the tests revealed sensitivity for anti-LID-1 (63.2%), anti-ND-O-LID (57.9%), qPCR SSS (36.8%), and smear microscopy (30.2%). However, the use of RF allowed for an expressive increase in sensitivity in the diagnosis of multibacillary leprosy (90.5%) and especially paucibacillary leprosy (70.6%). It is important to report that the specificity was 92.5%. CONCLUSION: The proposed model using RF allows for the diagnosis of leprosy with high sensitivity and specificity and the early identification of new cases among household contacts.


Asunto(s)
Ensayo de Inmunoadsorción Enzimática/métodos , Composición Familiar , Salud de la Familia , Lepra/diagnóstico , Mycobacterium leprae/genética , Mycobacterium leprae/inmunología , Reacción en Cadena en Tiempo Real de la Polimerasa/métodos , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Anticuerpos Antibacterianos/sangre , Inteligencia Artificial , Brasil , Niño , Preescolar , ADN Bacteriano/química , ADN Bacteriano/genética , ADN Ribosómico/química , ADN Ribosómico/genética , Femenino , Humanos , Estudios Longitudinales , Masculino , Persona de Mediana Edad , Técnicas de Diagnóstico Molecular/métodos , ARN Ribosómico 16S/genética , Sensibilidad y Especificidad , Pruebas Serológicas/métodos , Adulto Joven
14.
Immunobiology ; 224(4): 518-525, 2019 07.
Artículo en Inglés | MEDLINE | ID: mdl-31109749

RESUMEN

Hansen's disease (or leprosy) still persists as a serious public health issue. Its diagnosis is based primarily on the detection of clinical signs that are characteristic of the disease. Studies have pointed to the selection of a set of serological and cellular biomarkers of subclinical infection that result in an efficient diagnosis. The aim of this study was compare index cases and their household contacts to identify differentially expressed biomarkers of immune response in leprosy that could provide reliable evidence of subclinical infection in household contacts. The study population consisted of index cases with multibacillary form (IC, n = 13) and their household contacts (HC, n = 14). Serum cytokines and chemokines were quantified using the cytometric beads array (CBA) system. The humoral response was assessed by ELISA test. Flow cytometry was used to characterize the cellular immune response. Monocyte and CD4 + T lymphocytes frequency was significantly higher in IC. Both CD4+ and CD8 + T lymphocytes had a reduced CD25 expression in HC. The immunoglobulin (Ig)M profile anti- NDO-HSA, LID-1, and NDOLID antigens was significantly higher in IC. This study points to the monocyte and CD4+ lymphocyte frequency, as well as specific IgM profile, as predictors of subclinical infection in the household contacts.


Asunto(s)
Biomarcadores , Familia , Lepra/diagnóstico , Lepra/inmunología , Adolescente , Adulto , Anciano , Niño , Preescolar , Estudios Transversales , Citocinas/sangre , Femenino , Humanos , Inmunoglobulina M/inmunología , Lactante , Lepra/microbiología , Lepra/transmisión , Leucocitos/inmunología , Leucocitos/metabolismo , Masculino , Persona de Mediana Edad , Mycobacterium leprae/inmunología , Índice de Severidad de la Enfermedad
15.
Int J Exp Pathol ; 100(3): 161-174, 2019 06.
Artículo en Inglés | MEDLINE | ID: mdl-31124597

RESUMEN

This study evaluated the immune response of nude and BALB/c mice inoculated in the footpads (FP) with Mycobacterium leprae after 3, 5 and 8 months. At each timepoint peritoneal cells, peripheral blood, FP and popliteal lymph nodes (PLN) were collected. Peritoneal cell cultures were performed to measure the H2 O2 , O2 - , NO, IL-2, IL-4, IL-10, IL-12, IFN-γ and TNF levels. Serum levels of anti-PGL-I antibodies were also quantified. The results showed that the infection was progressive in nude mice with bacterial multiplication, development of macroscopic lesions in the FP and presence of bacilli in the PLN at 8 months. In BALB/c mice, the infection reached a plateau of bacillary multiplication at 5 months and regressed at 8 months. Histopathological analysis of FP revealed a mononuclear inflammatory infiltrate with a large number of neutrophils at 5 months, with a higher number in nude mice. At 8 months, the number of neutrophils decreased and the infiltrate was predominantly mononuclear in both mouse strains. There was no H2 O2, O2 - , IL-2, IL-4, IL-10 and IFN-γ production in the course of infection in nude mice; however, in BALB/c, O2 - and IL-12 production was higher at 5 months and NO, IFN-γ and TNF production was higher at 8 months when there was a decrease in the number of bacilli. The level of anti-PGL-I antibodies was higher in BALB/c mice. Thus, nude and BALB/c mice can be used as experimental models for the study of various aspects of leprosy.


Asunto(s)
Pie/patología , Lepra/patología , Mycobacterium leprae/inmunología , Lavado Peritoneal , Animales , Modelos Animales de Enfermedad , Interleucina-10/metabolismo , Lepra/inmunología , Ratones Endogámicos BALB C , Ratones Desnudos , Piel/inmunología , Piel/patología
16.
PLoS Negl Trop Dis ; 13(4): e0007318, 2019 04.
Artículo en Inglés | MEDLINE | ID: mdl-31017900

RESUMEN

BACKGROUND: Leprosy, caused by Mycobacterium leprae, affects over 200,000 people annually worldwide and remains endemic in the ethnically diverse, mountainous and underdeveloped southwestern provinces of China. Delayed diagnosis of leprosy persists in China, thus, additional knowledge to support early diagnosis, especially early diagnosis of paucibacillary (PB) patients, based on the host immune responses induced by specific M. leprae antigens is needed. The current study aimed to investigate leprosy patients and controls in Southwest China by comparing supernatants after stimulation with specific M. leprae antigens in an overnight whole-blood assay (WBA) to determine whether host markers induced by specific M. leprae antigens improve the diagnosis or discrimination of PB patients with leprosy. METHODOLOGY/PRINCIPAL FINDINGS: Leprosy patients [13 multibacillary (MB) patients and 7 PB patients] and nonleprosy controls [21 healthy household contacts (HHCs), 20 endemic controls (ECs) and 19 tuberculosis (TB) patients] were enrolled in this study. The supernatant levels of ten host markers stimulated by specific M. leprae antigens were evaluated by overnight WBA and multiplex Luminex assays. The diagnostic value in PB patients and ECs and the discriminatory value between PB patients and HHCs or TB patients were evaluated by receiver operator characteristics (ROC) analysis. ML2044-stimulated CXCL8/IL-8 achieved the highest sensitivity of 100%, with a specificity of 73.68%, for PB diagnosis. Compared to single markers, a 3-marker combination model that included ML2044-induced CXCL8/IL-8, CCL4/MIP-1 beta, and IL-6 improved the diagnostic specificity to 94.7% for PB patients. ML2044-stimulated IL-4 and CXCL8/IL-8 achieved the highest sensitivity (85.71% and 100%) and the highest specificity (95.24% and 84.21%) for discriminating PB patients from HHCs and TB patients, respectively. CONCLUSIONS: Our findings suggest that the host markers induced by specific M. leprae antigens in an overnight WBA increase diagnostic and discriminatory value in PB patients with leprosy, with a particularly strong association with interleukin 8.


Asunto(s)
Antígenos Bacterianos/inmunología , Sangre/inmunología , Inmunidad Innata , Inmunoensayo/métodos , Lepra Paucibacilar/diagnóstico , Lepra Paucibacilar/inmunología , Mycobacterium leprae/inmunología , Adulto , China , Citocinas/análisis , Pruebas Diagnósticas de Rutina/métodos , Femenino , Humanos , Masculino , Curva ROC , Sensibilidad y Especificidad , Adulto Joven
17.
J Infect Public Health ; 12(5): 656-659, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-30904499

RESUMEN

BACKGROUND AND OBJECTIVE: Leprosy is a chronic slowly progressive infection caused by Mycobacterium leprae that primarily affects the skin and peripheral nerves. Lepromatous leprosy is characterized by absence of T-cell responses to M. leprae and advanced clinical disease. It is frequently associated with the presence of autoantibodies, which might be related to CD19+CD5+ and CD19+CD5- B lymphocyte percentages. Therefore, the aim of this study was to evaluate the percentages of CD19+CD5+ and CD19+CD5- B cell subsets as well as the total B cells in lepromatous leprosy patients. MATERIALS AND METHODS: Twenty lepromatous leprosy patients and ten healthy subjects served as control were included in this study. Venous blood samples were analyzed by flow cytometry to determine the B cell subsets and total B cell percentages. RESULTS: Compared to healthy controls, the percentages of CD19+CD5+ B cell subset and total B cells were found to be significantly higher in the patient group. While, the percentage of CD19+CD5- B cell subset was found to be higher in the patient group than the control without any significantly difference. Regarding the eye affection, the percentage of total B cells was observed to be significantly higher in affected patients compared to the non-affected group. CONCLUSION: The observed significant increases in CD19+CD5+ and total B cell percentages in patients with lepromatous leprosy suggests a possible role of these cells in the disorganized protective immune response as well as the development of eye complications in these patients.


Asunto(s)
Enfermedades Autoinmunes/inmunología , Subgrupos de Linfocitos B/inmunología , Antígenos CD5/inmunología , Lepra Lepromatosa/inmunología , Enfermedades Autoinmunes/microbiología , Estudios de Casos y Controles , Femenino , Citometría de Flujo , Humanos , Masculino , Mycobacterium leprae/inmunología , Factores de Riesgo , Piel/inmunología , Piel/microbiología
18.
BMC Infect Dis ; 19(1): 22, 2019 Jan 07.
Artículo en Inglés | MEDLINE | ID: mdl-30616580

RESUMEN

BACKGROUND: Early detection of leprosy and multidrug therapy are crucial to achieve zero transmission and zero grade II incapacities goals of World Health Organization. Leprosy is difficult to diagnose because clinical forms vary and there are no gold standard methods to guide clinicians. The serological rapid tests aid the clinical diagnosis and are available for field use. They are easy to perform, do not require special equipment or refrigeration and are cheaper than the molecular tests. METHODS: We evaluated the performance of two rapid serological tests (PGL1 and NDO-LID) in the discrimination of leprosy cases from healthy individuals at the Alfredo da Matta Foundation, a reference center for the disease in Manaus, Amazonas, Brazil. PGL1 and NDO-LID rapid tests are capable of detecting specific antibodies of M. leprae, IgM and IgM/IgG, respectively. A total of 530 healthy subjects and 171 patients (50 with paucibacillary and 121 multibacillary leprosy) were included in the study. RESULTS: Among the paucibacillary leprosy patients, the sensitivity was 34.0 and 32.0% for the NDO-LID and PGL1, respectively. In multibacillary leprosy patients, the NDO-LID sensitivity was 73.6% and the PGL1 was 81.0%. Serological tests demonstrated specificities of 75.9% for PGL-1 and 81.7% for NDO-LID. The positive predictive value (PPV), negative predictive value (NPV) and accuracy in multibacillary patients were 47.9, 93.1, and 80.2% respectively for the NDO-LID, and 43.4, 94.6 76.8% for PGL1. CONCLUSIONS: The tests showed limited capacity in the diagnosis of the disease, however, the high negative predictive value of the tests indicates a greater chance of true negatives in this group favoring exclusion of leprosy. This characteristic of the ML flow test is important in aiding clinical Diagnosis, especially in a region endemic to the disease and with other confounding skin conditions.


Asunto(s)
Antígenos Bacterianos/inmunología , Glucolípidos/inmunología , Lepra/diagnóstico , Pruebas Serológicas/métodos , Adolescente , Adulto , Anciano , Anticuerpos Antibacterianos/sangre , Anticuerpos Antibacterianos/inmunología , Brasil , Estudios de Casos y Controles , Niño , Diagnóstico Precoz , Femenino , Humanos , Lepra/sangre , Lepra Multibacilar/diagnóstico , Lepra Paucibacilar/diagnóstico , Masculino , Persona de Mediana Edad , Mycobacterium leprae/inmunología , Sensibilidad y Especificidad
19.
Am J Trop Med Hyg ; 100(2): 377-385, 2019 02.
Artículo en Inglés | MEDLINE | ID: mdl-30652669

RESUMEN

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


Asunto(s)
Linfocitos T CD4-Positivos/inmunología , Linfocitos T CD8-positivos/inmunología , Eritema Nudoso/inmunología , Lepra Lepromatosa/inmunología , Mycobacterium leprae/patogenicidad , Factor de Necrosis Tumoral alfa/inmunología , Adolescente , Adulto , Anciano , Linfocitos T CD4-Positivos/microbiología , Linfocitos T CD8-positivos/microbiología , Estudios de Casos y Controles , Eritema Nudoso/genética , Eritema Nudoso/patología , Femenino , Regulación de la Expresión Génica , Interacciones Huésped-Patógeno/genética , Interacciones Huésped-Patógeno/inmunología , Humanos , Memoria Inmunológica , Inmunofenotipificación , Interferón gamma/genética , Interferón gamma/inmunología , Interleucina-10/genética , Interleucina-10/inmunología , Lepra Lepromatosa/genética , Lepra Lepromatosa/patología , Masculino , Persona de Mediana Edad , Mycobacterium leprae/crecimiento & desarrollo , Mycobacterium leprae/inmunología , Cultivo Primario de Células , Factor de Transcripción STAT4/genética , Factor de Transcripción STAT4/inmunología , Transducción de Señal , Proteínas de Dominio T Box/genética , Proteínas de Dominio T Box/inmunología , Factor de Necrosis Tumoral alfa/genética
20.
BMC Infect Dis ; 19(1): 52, 2019 Jan 14.
Artículo en Inglés | MEDLINE | ID: mdl-30642265

RESUMEN

BACKGROUND: Leprosy is an ideal human disease to study T cell regulation as patients show correlation between cytokine skewed Th1-Th2 responses and clinical forms of the disease. The Role of transcription factors on the modulation of Th1 and Th2 responses by M. leprae antigens has not been adequately studied. In the present study, we studied the effect of M. leprae antigens on transcription factors STAT-4, STAT-6 and CREB and their correlation with Th1/Th2 cell mediated immune responses in leprosy. METHODS: Leprosy patients of both categories of tuberculoid leprosy (BT/TT) and lepromatous leprosy (BL/LL) were selected from the OPD of NJ1L & OMD, (ICMR), Agra and healthy individuals (H) were chosen from the staff and students working in the institute. Peripheral blood mononuclear cells (PBMCs) of the study subjects were stimulated with M. leprae antigens (WCL, MLSA, and PGL-1). Sandwich ELISA was done in the culture supernatants of healthy and leprosy patients to detect IL-4, IL-10 and IFN-γ. Further, expression of IFN-γ and IL-4 and activation of STAT4, STAT6 and CREB transcription factors in CD4+ T cell with or without stimulation of M. leprae antigens was investigated by flow cytometry. RESULTS: Lepromatous leprosy patients showed significantly lower IFN-γ and higher IL-4 levels in culture supernatant and significantly low expression of IFN-γ and higher expression of IL-4 by CD4+ T cells than healthy individuals with or without antigenic stimulation. Antigenic stimulation significantly increased IL-10 in BL/LL patients but not in BT/TT patients or healthy individuals. PGL-1 stimulation led to significantly higher activation of STAT-6 in BT/TT and BL/LL patients in comparison to healthy individuals. All the three antigens led to activation of CREB in healthy and BT/TT patients but not in BL/LL patients. CONCLUSION: Our findings show that M. leprae antigens differentially modulate activation of T cell transcription factors STAT-4/STAT-6 and CREB. These transcription factors are well known to regulate Th1 and Th2 mediated immune response which in turn could play vital role in the clinical manifestations of leprosy. These observations may help to determine how these T cell transcription factors affect the development of immune dysfunction and whether these new pathways have a role in immunomodulation in intracellular diseases like leprosy and TB.


Asunto(s)
Proteína de Unión a Elemento de Respuesta al AMP Cíclico/metabolismo , Lepra/inmunología , Mycobacterium leprae/inmunología , Factor de Transcripción STAT4/metabolismo , Factor de Transcripción STAT6/metabolismo , Adulto , Antígenos Bacterianos/farmacología , Linfocitos T CD4-Positivos/efectos de los fármacos , Linfocitos T CD4-Positivos/inmunología , Linfocitos T CD4-Positivos/metabolismo , Estudios de Casos y Controles , Proteína de Unión a Elemento de Respuesta al AMP Cíclico/inmunología , Citocinas/metabolismo , Humanos , Lepra/metabolismo , Leucocitos Mononucleares/efectos de los fármacos , Leucocitos Mononucleares/microbiología , Persona de Mediana Edad , Mycobacterium leprae/patogenicidad , Factor de Transcripción STAT4/inmunología , Factor de Transcripción STAT6/inmunología , Células TH1/efectos de los fármacos , Células TH1/inmunología , Células TH1/metabolismo , Células Th2/efectos de los fármacos , Células Th2/inmunología , Células Th2/metabolismo
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