Leishmaniose visceral e susceptibilidade genética

Visceral leishmaniasis is a serious infectious disease caused by an obligate intracellular protozoan of the genus Leishmania. The disease encompasses a wide spectrum of clinical manifestations, which can range from asymptomatic cases, to the classical form of the disease characterized by hepatosplenomegaly, fever and wasting, and even the more severe bleeding that can progress to death. Some factors can alter the severity of clinical manifestations, among them the genetic predisposition. Through research of genetic polymorphism it is possible to evaluate which genes may be related to susceptibility to infection and predisposition to the most severe forms of the diseaseA leishmaniose visceral é uma grave doença infecciosa causada por um protozoário intracelular obrigatório do gênero Leishmania. A doença abrange um grande espectro de manifestações clínicas que podem variar desde infecções assintomáticas, passando pela forma clássica da doença caracterizada por hepatoesplenomegalia, febre e caquexia, chegando até formas mais graves com sangramentos que podem evoluir para a morte. Alguns fatores podem alterar a gravidade das manifestações clínicas, sendo um deles a predisposição genética. Por meio da pesquisa de polimorfismos genéticos é possível avaliar quais os genes que podem estar relacionados com a susceptibilidade à infecção e com a predisposição às formas mais graves da doenç

Disease Tolerance and Pathogen Resistance Genes May Underlie Trypanosoma cruzi Persistence and Differential Progression to Chagas Disease Cardiomyopathy

Chagas disease is caused by infection with the protozoan Trypanosoma cruzi and affects over 8 million people worldwide. In spite of a powerful innate and adaptive immune response in acute infection, the parasite evades eradication, leading to a chronic persistent infection with low parasitism. Chronically infected subjects display differential patterns of disease progression. While 30% develop chronic Chagas disease cardiomyopathy (CCC)—a severe inflammatory dilated cardiomyopathy—decades after infection, 60% of the patients remain disease-free, in the asymptomatic/indeterminate (ASY) form, and 10% develop gastrointestinal disease. Infection of genetically deficient mice provided a map of genes relevant for resistance to T. cruzi infection, leading to the identification of multiple genes linked to survival to infection. These include pathogen resistance genes (PRG) needed for intracellular parasite destruction, and genes involved in disease tolerance (protection against tissue damage and acute phase death—DTG). All identified DTGs were found to directly or indirectly inhibit IFN-γ production or Th1 differentiation. We hypothesize that the absolute need for DTG to control potentially lethal IFN-γ PRG activity leads to T. cruzi persistence and establishment of chronic infection. IFN-γ production is higher in CCC than ASY patients, and is the most highly expressed cytokine in CCC hearts. Key DTGs that downmodulate IFN-γ, like IL-10, and Ebi3/IL27p28, are higher in ASY patients. Polymorphisms in PRG and DTG are associated with differential disease progression. We thus hypothesize that ASY patients are disease tolerant, while an imbalance of DTG and IFN-γ PRG activity leads to the inflammatory heart damage of CCC

Efeito da acupuntura na variabilidade da frequência cardíaca em indivíduos com esclerose múltipla: um protocolo para ensaio randomizado controlado duplo cego

Backgroung: the growing of patients with multiple sclerosis seeking acupuncture treatment is based on clinical reports of improvements in symptoms. Considering that autonomic impairment, including cardiovascular autonomic dysfunction, is not uncommon in patients with MS, neuromodulation with acupuncture could be an interesting tool to change heart rate variability in this population. Objective: to evaluate heart rate variability in patients with multiple sclerosis, during the application of acupuncture, in order to analyze the behavior of the autonomic nervous system before, during and after therapy and changes in condition after a longitudinal intervention. Methods: a double-blinded randomized sham-controlled crossover trial with a 1:1 allocation ratio will be conducted, with 40 individuals without a previous illness, who will constitute the control group, and 40 individuals with Multiple Sclerosis, who will constitute the experimental group, paired by age and sex. All participants will undertake active or sham acupuncture sessions. Discussion: according to the studies found, cardiovascular autonomic dysfunction is expected, with alterations in heart rate variability. Although neuromodulation with acupuncture can control pain and inflammation, there are still difficulties in affirming whether the balance between the sympathetic and parasympathetic systems can be changed by acupuncture. Trial registration: We registered this trial on ClinicalTrials.gov, ID: NCT05523466Introdução: o crescimento de pacientes com esclerose múltipla que procuram tratamento com acupuntura é baseado em relatos clínicos de melhora dos sintomas. Considerando que o comprometimento autonômico, incluindo a disfunção autonômica cardiovascular, não é incomum em pacientes com EM a neuromodulação com acupuntura pode ser uma ferramenta interessante para alterar a variabilidade da frequência cardíaca nessa população. Objetivo: avaliar a variabilidade da frequência cardíaca em pacientes com esclerose múltipla, durante a aplicação da Acupuntura, a fim de analisar o comportamento do sistema nervoso autônomo antes, durante e após a terapia e as mudanças na condição após uma intervenção longitudinal. Métodos: será realizado um ensaio clínico cruzado, randomizado, placebo-controlado, duplo-cego, com proporção de alocação de 1:1, com 40 indivíduos sem doença prévia, que constituirão o grupo controle, e 40 indivíduos com Esclerose Múltipla, que constituirão o grupo experimental. grupo, pareado por idade e sexo. Todos os participantes realizarão sessões de acupuntura ativas ou simuladas. Discussão: de acordo com os estudos encontrados, é esperada disfunção autonômica cardiovascular, com alterações na variabilidade da frequência cardíaca. Embora a neuromodulação com acupuntura possa controlar a dor e a inflamação, ainda há dificuldades em afirmar se o equilíbrio entre os sistemas simpático e parassimpático pode ser alterado pela acupuntura. Registro do estudo: registramos este estudo em ClinicalTrials.gov, ID: NCT0552346

Genetic susceptibility to Chagas disease cardiomyopathy: involvement of several genes of the innate immunity and chemokine-dependent migration pathways

Abstract\ud \ud Background\ud Chagas disease, caused by the protozoan Trypanosoma cruzi is endemic in Latin America. Thirty percent of infected individuals develop chronic Chagas cardiomyopathy (CCC), an inflammatory dilated cardiomyopathy that is, by far, the most important clinical consequence of T. cruzi infection. The others remain asymptomatic (ASY). A possible genetic component to disease progression was suggested by familial aggregation of cases and the association of markers of innate and adaptive immunity genes with CCC development. Migration of Th1-type T cells play a major role in myocardial damage.\ud \ud \ud Methods\ud Our genetic analysis focused on CCR5, CCL2 and MAL/TIRAP genes. We used the Tag SNPs based approach, defined to catch all the genetic information from each gene. The study was conducted on a large Brazilian population including 315 CCC cases and 118 ASY subjects.\ud \ud \ud Results\ud The CCL2rs2530797A/A and TIRAPrs8177376A/A were associated to an increase susceptibility whereas the CCR5rs3176763C/C genotype is associated to protection to CCC. These associations were confirmed when we restricted the analysis to severe CCC, characterized by a left ventricular ejection fraction under 40%.\ud \ud \ud Conclusions\ud Our data show that polymorphisms affecting key molecules involved in several immune parameters (innate immunity signal transduction and T cell/monocyte migration) play a role in genetic susceptibility to CCC development. This also points out to the multigenic character of CCC, each polymorphism imparting a small contribution. The identification of genetic markers for CCC will provide information for pathogenesis as well as therapeutic targets.FAPES

Identificação de polimorfismos genéticos com impacto no desenvolvimento e progressão da leishmaniose visceral em indivíduos de áreas endêmicas do Maranhão e Piauí

A leishmaniose visceral constitui grave doença infecciosa causada por um protozoário parasita intracelular obrigatório. Alguns fatores podem alterar a gravidade das manifestações clínicas, sendo um deles a predisposição genética. Este estudo investigou polimorfismos dos genes TGFB1, IL8 e IL6, que são citocinas relacionadas com o desencadeamento e a gravidade da doença, visando identificar fatores de susceptibilidade. Os polimorfismos TGFB1 -509 C/T e TGFB1 +869 T/C, IL8 -251A/T e IL6 -174G/C foram analisados por PCR-RFLP, em 198 pacientes com leishmaniose visceral (LV), 98 indivíduos com infecção assintomática (teste de hipersensibilidade tardia - DTH+) e 100 indivíduos sem evidências de infecção (DTH-). O alelo T na posição -509 do gene TGFB1 conferiu risco duas vezes maior de desenvolver LV ou ser positivo para o teste DTH (p = 0,007, OR = 1,9 [1,19-3,02]), em comparação com indivíduos DTH-. Os resultados sugerem uma associação do polimorfismo TGFB1 -509C/T com a susceptibilidade à LV, podendo contribuir para o desencadeamento da doença clínica.Visceral leishmaniasis is a serious protozoan infectious disease caused by an obligate intracellular parasite. Some factors can affect the severity of the clinical manifestations; one of which is genetic susceptibility. This study investigated polymorphisms in the TGFB1, IL8 and IL6 genes, which are cytokines related with the onset and severity of the disease, to look for genetic susceptibility factors. Polymorphisms at TGFB1 -509C/T and +869T/C, and IL8 - 251A/T and IL6 -174G/C were analyzed by a PCR-RFLP technique, in 198 patients with Visceral Leishmaniasis (VL), 98 individuals with asymptomatic infection (positive delayed-type hypersensitivity, DTH+) and 100 individuals with no evidence of infection (DTH-). The T allele of the TGFB1 polymorphism in position -509C/T conferred a two risk fold to develop LV or to be DTH+ (p=0.007; OR=1.9 [1.19 - 3.02]) when compared with DTH- individuals. We suggest the TGFB1 -509C/T polymorphism is associated with susceptibility to LV and may contribute to development of the clinical disease

TESAcruzi: confirmatory test for Chagas disease diagnosis using serum samples collected by fingerprint, in filter paper, from children (0-5 years old) living in different states of Brazil

A doença de Chagas ainda é causa importante da morte de milhares de pessoas nos países em desenvolvimento, sendo de grande importância a identificação e confirmação de indivíduos chagásicos, principalmente mulheres e crianças. Neste trabalho avaliamos o valor clínico dos resultados do teste sorológico TESAcruzi como confirmatório de infecção chagásica em amostras de sangue colhidas em papel de filtro . Foram estudadas 8.788 amostras de sangue coletadas em papel filtro (tipo Whatman nº4) de crianças de 0 a 5 anos de idade incompletos de zonas rurais de 13 estados do Brasil, enviadas ao Laboratório de Soroepidemiologia e Imunobiologia do Instituto de Medicina Tropical de São Paulo pelo Laboratório de Chagas do Hospital das Clínicas-UFG, para confirmação e controle de qualidade da infecção chagásica. Foram utilizados os testes sorológicos ELISA - BIOELISACRUZI, IFI - IMUNOCRUZI e WB - TESAcruzi (BioMérieux-Brasil). Das 8.788 amostras de sangue analisadas, 166 (1,9%) foram reagentes por ELISA (cut off 0,3) e 313 (3,6%) por IFI a partir de 1/40. Todas as amostras reagentes ou duvidosas foram ensaiadas por TESAcruzi para confirmação dos resultados. Foram reagentes 77 eluatos (0,9%). Considerando que o TESAcruzi apresenta 100% de sensibilidade e 99,6% de especificidade, os valores preditivos positivos e negativos obtidos, conferem aos resultados um alto valor clínico para a confirmação de resultados positivos, negativos e inconclusivos na sorologia da doença de Chagas. A introdução do TESAcruzi na sorologia da doença de Chagas é uma ferramenta importante quando se deseja confirmar casos com sorologia duvidosa ou inconclusiva.Identifying and confirming Chagas disease patients is a goal to be achieved at this moment, just when many countries from Latin America had announced its control an/or eradication. In this project we studied the TESAcruzi as confirmatory test for Chagas Disease diagnosis using serum samples collected from children (0-5 years old) living in different states of Brazil and selected by statistics criteria. The study is part of the seroepidemiological survey that is occurring in Brazil looking for ongenital or acquired Chagas disease. Blood samples collected by fingerprint in nº4 Whatman filter paper (10% of total and all reagents and inconclusive samples) were sent to our laboratory by central laboratory located in Goiania - Goias to confirm previous results. For this we used traditional commercial reagents, IgG indirect immunofluorescence - IgG-IFI, enzyme immunoassay - IgG - ELISA and introduced TESAcruzi, western blotting reagent, recently registered by BioMerieux S.A. From 8.788 samples 166 (1.9%) were reagents in IgG-ELISA (C.O = 0.300) and 313 (3.64%) by IgG IFI (C.O 1/40). From these, 77 (0.9%) were reagents in TESAcruzi. Considering the predictive values of TESAcruzi (NPV = 100% and PPV = 99.5%) the results obtained had high clinical value to define the Chagasic patients. TESAcruzi reagent seems to be an important tool for Chagas disease diagnosis when it is necessary to confirm reagents or inconclusive results

TESAcruzi: confirmatory test for Chagas disease diagnosis using serum samples collected by fingerprint, in filter paper, from children (0-5 years old) living in different states of Brazil

A doença de Chagas ainda é causa importante da morte de milhares de pessoas nos países em desenvolvimento, sendo de grande importância a identificação e confirmação de indivíduos chagásicos, principalmente mulheres e crianças. Neste trabalho avaliamos o valor clínico dos resultados do teste sorológico TESAcruzi como confirmatório de infecção chagásica em amostras de sangue colhidas em papel de filtro . Foram estudadas 8.788 amostras de sangue coletadas em papel filtro (tipo Whatman nº4) de crianças de 0 a 5 anos de idade incompletos de zonas rurais de 13 estados do Brasil, enviadas ao Laboratório de Soroepidemiologia e Imunobiologia do Instituto de Medicina Tropical de São Paulo pelo Laboratório de Chagas do Hospital das Clínicas-UFG, para confirmação e controle de qualidade da infecção chagásica. Foram utilizados os testes sorológicos ELISA - BIOELISACRUZI, IFI - IMUNOCRUZI e WB - TESAcruzi (BioMérieux-Brasil). Das 8.788 amostras de sangue analisadas, 166 (1,9%) foram reagentes por ELISA (cut off 0,3) e 313 (3,6%) por IFI a partir de 1/40. Todas as amostras reagentes ou duvidosas foram ensaiadas por TESAcruzi para confirmação dos resultados. Foram reagentes 77 eluatos (0,9%). Considerando que o TESAcruzi apresenta 100% de sensibilidade e 99,6% de especificidade, os valores preditivos positivos e negativos obtidos, conferem aos resultados um alto valor clínico para a confirmação de resultados positivos, negativos e inconclusivos na sorologia da doença de Chagas. A introdução do TESAcruzi na sorologia da doença de Chagas é uma ferramenta importante quando se deseja confirmar casos com sorologia duvidosa ou inconclusiva.Identifying and confirming Chagas disease patients is a goal to be achieved at this moment, just when many countries from Latin America had announced its control an/or eradication. In this project we studied the TESAcruzi as confirmatory test for Chagas Disease diagnosis using serum samples collected from children (0-5 years old) living in different states of Brazil and selected by statistics criteria. The study is part of the seroepidemiological survey that is occurring in Brazil looking for ongenital or acquired Chagas disease. Blood samples collected by fingerprint in nº4 Whatman filter paper (10% of total and all reagents and inconclusive samples) were sent to our laboratory by central laboratory located in Goiania - Goias to confirm previous results. For this we used traditional commercial reagents, IgG indirect immunofluorescence - IgG-IFI, enzyme immunoassay - IgG - ELISA and introduced TESAcruzi, western blotting reagent, recently registered by BioMerieux S.A. From 8.788 samples 166 (1.9%) were reagents in IgG-ELISA (C.O = 0.300) and 313 (3.64%) by IgG IFI (C.O 1/40). From these, 77 (0.9%) were reagents in TESAcruzi. Considering the predictive values of TESAcruzi (NPV = 100% and PPV = 99.5%) the results obtained had high clinical value to define the Chagasic patients. TESAcruzi reagent seems to be an important tool for Chagas disease diagnosis when it is necessary to confirm reagents or inconclusive results

Western blotting method (TESAcruzi) as a supplemental test for confirming the presence of anti-Trypanosoma cruzi antibodies in finger prick blood samples from children aged 0-5 years in Brazil

Some Latin American countries have plans for total control and/or eradication of Chagas disease by the main vector (Triatoma infestans) and by blood transfusion. To achieve this, patients with Chagas disease must be identified. A Western blotting test, TESAcruzi, is described as a supplemental test for diagnosis of Chagas disease using samples collected from children <5 years living in different states of Brazil. Blood samples collected by finger prick on filter paper were sent to the test laboratory by a central laboratory to confirm results obtained previously. Ten percent of negative samples, all doubtful and all positive samples were received. Commercial reagents, IgG indirect immunofluorescence, enzyme immunoassay, and a recently introduced TESAcruzi test were used. From 8788 samples, 163 (1.85%) were reactive by IgG-ELISA and 312 (3.55%) by IgG IIF. From these, 77 (0.87%) were reactive in the TESAcruzi test. The results had high clinical value to identify those truly infected. (C) 2010 Elsevier B.V. All rights reserved

Interferon-gamma and other inflammatory mediators in cardiomyocyte signaling during Chagas disease cardiomyopathy.

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