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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

Caracterização da resposta imune in situ nas lesões de hanseníase indeterminada / Characterization of the in situ immune response in indeterminate leprosy lesions

Alvarenga, Marcia Lanzoni de 17 August 2015 (has links)
A forma indeterminada é a fase inicial da hanseníase, que se caracteriza histologicamente pelo infiltrado inflamatório leve, não granulomatoso, de linfócitos e histiócitos ao redor de vasos, anexos e nervos. No local de entrada do M. leprae, as células apresentadoras de antígeno do tipo células dendríticas são as primeiras a encontrar o bacilo. Este, no interior de células dendríticas, desencadeia a produção local de citocinas e quimiocinas, que resultam em proliferação de linfócitos T helper 1 ou T helper 2, assim definindo uma resposta imune celular ou humoral, respectivamente. As lesões tuberculoides mostram predominância das citocinas de padrão Th1 como IL-2, TNF-alfa, IFN-y, IL-12 e IL-18, enquanto que nas lesões virchowianas predominam citocinas de padrão Th2, como IL-4, IL-5, IL-10 e TGF-beta. Na pele, as principais células dendríticas são células dendríticas mieloides, células de Langerhans e alguns dendrócitos dérmicos. São identificadas respectivamente pela expressão imuno-histoquímica de S100, CD1a e Fator XIIIa. Células de Langerhans e dendrócitos dérmicos Fator XIIIa positivos estão aumentados em quantidade nas lesões tuberculoides quando comparadas com lesões virchowianas. Os objetivos do presente estudo foram: 1) caracterizar a inflamação \"in situ\" na hanseníase indeterminada através da quantificação das marcações imuno-histoquímicas de: CD57, CD4, CD8, CD1a, S100, FXIIIa, CD68, Foxp3, CD123, IL-1, IL-2r, IL-4, IL-6, IL-8, IL-10, IL-12, IL-18, IFN-, TNF-alfa, TGF-beta, iNOS, granzima B, receptor Toll-like 2/4, e antígeno BCG, 2) comparar o perfil fenotípico e citocínico das lesões na hanseníase indeterminada entre grupos de reação de Mitsuda positiva e negativa, a fim de investigar se existem padrões que possam prever para qual forma a doença evoluiria, e 3) revisar a histopatologia da forma indeterminada através da análise semiquantitativa das alterações vistas à coloração de hematoxilina/eosina. Foram selecionadas 15 lesões de pacientes com hanseníase indeterminada. Foram usados grupos controles de expressão de Fator XIIIa e CD1a em 10 casos de pele normal. A histopatologia mostrou discretas alterações epidérmicas, como alteração vacuolar e exocitose de linfócitos (33% dos casos cada), apoptose de queratinócitos (26%), atrofia e acantose (06% dos casos cada); infiltrado inflamatório linfomononuclear neural (100%), perivascular superficial (100%), perivascular profundo (93%), peri-écrino (40%) e peri-folículo pilossebáceo (20%), além de melanófagos em 93% dos casos. Esses achados mostraram que nem sempre todos os ambientes estão acometidos por inflamação na histopatologia. Em 66% dos pacientes foi encontrado antígeno bacilar (por Fite-Faraco ou técnica imuno-histoquímica anti-BCG), portanto a forma indeterminada não deve ser considerada sistematicamente como paucibacilar. Não houve diferença significativa de padrões de marcadores entre os grupos Mitsuda positivo e negativo. No microambiente inflamatório das lesões houve expressões significativas de TLR 2/4, Fator XIIIa, CD4, CD8, IL-2r, IL-4, IL-10, iNOS e TGF-beta. A expressão importante de IL-4, IL-10 e TGF- beta nas lesões de hanseníase indeterminada significaram tendência de resposta imune para o polo Th2, um ambiente de tolerância à permanência do bacilo. A baixa expressão de IFN-y colaborou para a inexpresiva resposta Th1. Não houve diferença significativa na expressão de CD1a entre as lesões e pele normal. Fator XIIIa foi expresso em mais que 50 células/mm2 em todos os casos, com quantidades significativamente maiores que outras células dendríticas nas lesões (S100, CD68, CD123) e que a pele normal. Estes achados demonstraram a importância dos dendrócitos dérmicos Fator XIIIa positivos na apresentação de antígeno na fase inicial da hanseníase / The indeterminate form is the initial stage of leprosy, which is characterized histologically by mild inflammatory infiltrate, non granulomatous, with lymphocytes and histiocytes around vessels, nerves and adnexals. When M. leprae enter the host, antigen-presenting cells of dendritic type are the first cells to find the bacillus. Once inside dendritic cells, the bacillus elicits local production of cytokines and chemokines, which result in proliferation of T lymphocytes helper 1 or T helper 2, thereby defining a cellular or humoral immune response, respectively. The tuberculoid lesions show predominance of Th1 cytokines such as IL-2, TNF-alfa, IFN-y, IL-12 and IL-18, whereas in the lepromatous lesions predominate cytokines of Th2 pattern such as IL-4, IL-5 IL-10 and TGF-beta. In the skin, main dendritic cells are myeloid dendritic cells, Langerhans cells, and some dermal dendrocytes. They are identified respectively by immunohistochemical expression of S100, CD1a and Factor XIIIa. Langerhans cells and dermal dendrocytes Factor XIIIa positive are increased in number in tuberculoid lesions compared with lepromatous lesions. The objectives of this study were: 1) to characterize \"in situ\" inflammation in indeterminate leprosy through the quantification of immunohistochemical markers: CD57, CD4, CD8, CD1a, S100, FXIIIa, CD68, Foxp3, CD123, IL-1, IL-2r, IL-4, IL-6, IL-8, IL-10, IL-12, IL-18, IFN-y, TNF-alfa, TGF-beta, iNOS, granzyme B, Toll-like receptor 2/4, and BCG antigen, 2) compare the phenotypic and cytokinic profile of indeterminate leprosy lesions between positive and negative Mitsuda reaction groups in order to investigate if there are patterns that can predict which way the disease may evolve, and 3 ) review the histopathology of the indetermate form by semi-quantitative analysis of changes seen in hematoxylin / eosin. Fifteen lesions of patients with indeterminate leprosy were selected. There was used control groups of Factor XIIIa and CD1a expression in 10 cases of normal skin. Histopathology showed discrete epidermal changes, such as vacuolar changes and lymphocyte exocytosis (in 33% of cases each), keratinocyte apoptosis (26%), atrophy and acanthosis (in 06% of cases each); neural lymphocytic inflammatory infiltrate (100%), superficial perivascular (100%), deep perivascular (93%), peri-eccrine (40%), peri-pilosebaceous follicle (20%), and melanophages in 93% of cases. These findings showed that not always all environments are affected by inflammation in histopathology. In 66% of patients it was found bacterial antigen (by Fite-Faraco or immunohistochemical technique anti-BCG), so the indeterminate form should not be systematically considered as paucibacillary. There was no significant difference in phenotypic and cytokinic patterns between the positive and negative Mitsuda groups. In the microenvironment of inflammatory lesions there was significant expression of TLR 2/4, Factor XIIIa, CD4, CD8, IL-2r, IL-4, IL-10, TGF-beta and iNOS. The important expression of IL-4, IL-10 and TGF-beta in indeterminate leprosy meant tendency to Th2 immune response pole, an environment of tolerance to permanence of bacillus. Low IFN-? expression contributed to the negligible Th1 response. There was no significant difference in the expression of CD1a between the lesions and normal skin. Factor XIIIa was expressed as greater than 50 cells / mm2 in all cases, with significantly larger quantities than other dendritic cells in lesions (S100, CD68, CD123) and than normal skin. These findings demonstrate the importance of Factor XIIIa positive dermal dendrocytes in antigen presentation at the initial stage of leprosy
2

Caracterização da resposta imune in situ nas lesões de hanseníase indeterminada / Characterization of the in situ immune response in indeterminate leprosy lesions

Marcia Lanzoni de Alvarenga 17 August 2015 (has links)
A forma indeterminada é a fase inicial da hanseníase, que se caracteriza histologicamente pelo infiltrado inflamatório leve, não granulomatoso, de linfócitos e histiócitos ao redor de vasos, anexos e nervos. No local de entrada do M. leprae, as células apresentadoras de antígeno do tipo células dendríticas são as primeiras a encontrar o bacilo. Este, no interior de células dendríticas, desencadeia a produção local de citocinas e quimiocinas, que resultam em proliferação de linfócitos T helper 1 ou T helper 2, assim definindo uma resposta imune celular ou humoral, respectivamente. As lesões tuberculoides mostram predominância das citocinas de padrão Th1 como IL-2, TNF-alfa, IFN-y, IL-12 e IL-18, enquanto que nas lesões virchowianas predominam citocinas de padrão Th2, como IL-4, IL-5, IL-10 e TGF-beta. Na pele, as principais células dendríticas são células dendríticas mieloides, células de Langerhans e alguns dendrócitos dérmicos. São identificadas respectivamente pela expressão imuno-histoquímica de S100, CD1a e Fator XIIIa. Células de Langerhans e dendrócitos dérmicos Fator XIIIa positivos estão aumentados em quantidade nas lesões tuberculoides quando comparadas com lesões virchowianas. Os objetivos do presente estudo foram: 1) caracterizar a inflamação \"in situ\" na hanseníase indeterminada através da quantificação das marcações imuno-histoquímicas de: CD57, CD4, CD8, CD1a, S100, FXIIIa, CD68, Foxp3, CD123, IL-1, IL-2r, IL-4, IL-6, IL-8, IL-10, IL-12, IL-18, IFN-, TNF-alfa, TGF-beta, iNOS, granzima B, receptor Toll-like 2/4, e antígeno BCG, 2) comparar o perfil fenotípico e citocínico das lesões na hanseníase indeterminada entre grupos de reação de Mitsuda positiva e negativa, a fim de investigar se existem padrões que possam prever para qual forma a doença evoluiria, e 3) revisar a histopatologia da forma indeterminada através da análise semiquantitativa das alterações vistas à coloração de hematoxilina/eosina. Foram selecionadas 15 lesões de pacientes com hanseníase indeterminada. Foram usados grupos controles de expressão de Fator XIIIa e CD1a em 10 casos de pele normal. A histopatologia mostrou discretas alterações epidérmicas, como alteração vacuolar e exocitose de linfócitos (33% dos casos cada), apoptose de queratinócitos (26%), atrofia e acantose (06% dos casos cada); infiltrado inflamatório linfomononuclear neural (100%), perivascular superficial (100%), perivascular profundo (93%), peri-écrino (40%) e peri-folículo pilossebáceo (20%), além de melanófagos em 93% dos casos. Esses achados mostraram que nem sempre todos os ambientes estão acometidos por inflamação na histopatologia. Em 66% dos pacientes foi encontrado antígeno bacilar (por Fite-Faraco ou técnica imuno-histoquímica anti-BCG), portanto a forma indeterminada não deve ser considerada sistematicamente como paucibacilar. Não houve diferença significativa de padrões de marcadores entre os grupos Mitsuda positivo e negativo. No microambiente inflamatório das lesões houve expressões significativas de TLR 2/4, Fator XIIIa, CD4, CD8, IL-2r, IL-4, IL-10, iNOS e TGF-beta. A expressão importante de IL-4, IL-10 e TGF- beta nas lesões de hanseníase indeterminada significaram tendência de resposta imune para o polo Th2, um ambiente de tolerância à permanência do bacilo. A baixa expressão de IFN-y colaborou para a inexpresiva resposta Th1. Não houve diferença significativa na expressão de CD1a entre as lesões e pele normal. Fator XIIIa foi expresso em mais que 50 células/mm2 em todos os casos, com quantidades significativamente maiores que outras células dendríticas nas lesões (S100, CD68, CD123) e que a pele normal. Estes achados demonstraram a importância dos dendrócitos dérmicos Fator XIIIa positivos na apresentação de antígeno na fase inicial da hanseníase / The indeterminate form is the initial stage of leprosy, which is characterized histologically by mild inflammatory infiltrate, non granulomatous, with lymphocytes and histiocytes around vessels, nerves and adnexals. When M. leprae enter the host, antigen-presenting cells of dendritic type are the first cells to find the bacillus. Once inside dendritic cells, the bacillus elicits local production of cytokines and chemokines, which result in proliferation of T lymphocytes helper 1 or T helper 2, thereby defining a cellular or humoral immune response, respectively. The tuberculoid lesions show predominance of Th1 cytokines such as IL-2, TNF-alfa, IFN-y, IL-12 and IL-18, whereas in the lepromatous lesions predominate cytokines of Th2 pattern such as IL-4, IL-5 IL-10 and TGF-beta. In the skin, main dendritic cells are myeloid dendritic cells, Langerhans cells, and some dermal dendrocytes. They are identified respectively by immunohistochemical expression of S100, CD1a and Factor XIIIa. Langerhans cells and dermal dendrocytes Factor XIIIa positive are increased in number in tuberculoid lesions compared with lepromatous lesions. The objectives of this study were: 1) to characterize \"in situ\" inflammation in indeterminate leprosy through the quantification of immunohistochemical markers: CD57, CD4, CD8, CD1a, S100, FXIIIa, CD68, Foxp3, CD123, IL-1, IL-2r, IL-4, IL-6, IL-8, IL-10, IL-12, IL-18, IFN-y, TNF-alfa, TGF-beta, iNOS, granzyme B, Toll-like receptor 2/4, and BCG antigen, 2) compare the phenotypic and cytokinic profile of indeterminate leprosy lesions between positive and negative Mitsuda reaction groups in order to investigate if there are patterns that can predict which way the disease may evolve, and 3 ) review the histopathology of the indetermate form by semi-quantitative analysis of changes seen in hematoxylin / eosin. Fifteen lesions of patients with indeterminate leprosy were selected. There was used control groups of Factor XIIIa and CD1a expression in 10 cases of normal skin. Histopathology showed discrete epidermal changes, such as vacuolar changes and lymphocyte exocytosis (in 33% of cases each), keratinocyte apoptosis (26%), atrophy and acanthosis (in 06% of cases each); neural lymphocytic inflammatory infiltrate (100%), superficial perivascular (100%), deep perivascular (93%), peri-eccrine (40%), peri-pilosebaceous follicle (20%), and melanophages in 93% of cases. These findings showed that not always all environments are affected by inflammation in histopathology. In 66% of patients it was found bacterial antigen (by Fite-Faraco or immunohistochemical technique anti-BCG), so the indeterminate form should not be systematically considered as paucibacillary. There was no significant difference in phenotypic and cytokinic patterns between the positive and negative Mitsuda groups. In the microenvironment of inflammatory lesions there was significant expression of TLR 2/4, Factor XIIIa, CD4, CD8, IL-2r, IL-4, IL-10, TGF-beta and iNOS. The important expression of IL-4, IL-10 and TGF-beta in indeterminate leprosy meant tendency to Th2 immune response pole, an environment of tolerance to permanence of bacillus. Low IFN-? expression contributed to the negligible Th1 response. There was no significant difference in the expression of CD1a between the lesions and normal skin. Factor XIIIa was expressed as greater than 50 cells / mm2 in all cases, with significantly larger quantities than other dendritic cells in lesions (S100, CD68, CD123) and than normal skin. These findings demonstrate the importance of Factor XIIIa positive dermal dendrocytes in antigen presentation at the initial stage of leprosy
3

Avaliação de diagnósticos do Mycobacterium spp. em populações diferencialmente susceptíveis.

Furini, Adriana Antônia da Cruz 18 November 2010 (has links)
Made available in DSpace on 2016-01-26T12:51:36Z (GMT). No. of bitstreams: 1 adrianafurini_dissert.pdf: 2158923 bytes, checksum: d683b1dc320b2c811cfcf58d6d1c21ac (MD5) Previous issue date: 2010-11-18 / Conselho Nacional de Desenvolvimento Científico e Tecnológico / Introduction. The diagnosis of paucibacillary forms of tuberculosis (TB), which mostly affects children, immunocompromised patients, transplanted and extra-pulmonary forms is limited by phenotypic techniques of smear and culture. Moreover, the diagnosis of mycobacteriosis, also has committed itself by the phenotypic methods. The polymerase chain reaction (PCR) and its variations, such as Nested-PCR (NPCR), has been described as promising techniques for rapid diagnosis of tuberculosis and mycobacteriosis. Objective. Evaluation of a NPCR protocol for detection of Mycobacterium tuberculosis in pulmonary and extrapulmonary anatomic sites of patients with clinical suspicion of TB. Subjects and Methods. Were included, prospectively, 24 pulmonary samples of 85 extrapulmonary, collected from 49 individuals HIV-seropositive and 28 HIV-seronegative and submitted to the gold standard method and NPCR targeting the transposon IS6110. Results. Tuberculosis was diagnosed in 11 patients (14,3%), with 54,5% of extrapulmonary forms and 45,5% pulmonary. The NPCR was positive in all, while the culture was positive in only seven of them. Smear positivity among the clinical specimens was 9,2%. The culture allowed the isolation of seven strains of M. tuberculosis and two M. avium complex (8,25%). The molecular positivity was described in 23,85% of samples. NPCR's performance against the culture, for pulmonary (n=22) and extrapulmonary samples (n = 83) was similar (100% sensitivity and specificity of approximately 83%). Positivity by NPCR was significantly greater than the isolation by culture among the extrapulmonary samples (p = 0,0042). Conclusions. The results suggest to perform further studies to corroborate the potential of NPCR-IS6110 for detection of mycobacterial genome in extrapulmonary TB, especially among immunocompromised. Furthermore, the detection of mycobacteria remains as diagnostic confirmation and the opportunity of investigation of the sensitivity profile, promoting effective treatment for any age and immune status. / Introdução. O diagnóstico das formas paucibacilares da tuberculose (TB), que acomete principalmente crianças, imunocomprometidos, transplantados e formas extrapulmonares é limitado pelas técnicas fenotípicas de baciloscopia e cultura. Ademais, o diagnóstico das micobacterioses, também apresenta-se comprometido pelos métodos fenotípicos. A reação da polymerase em cadeia (PCR) e suas variações, tais como a Nested-PCR (NPCR), tem sido descritas como técnicas promissoras para o rápido diagnóstico da tuberculose e micobacterioses. Objetivos. Avaliação de um protocolo de NPCR para detecção do complexo Mycobacterium tuberculosis em sítios anatômicos pulmonares e extrapulmonares de indivíduos com suspeita clínica de TB. Casuística e Método. Foram incluídas, prospectivamente, 24 amostras de sítios pulmonares e 85 extrapulmonares, coletadas a partir de 49 indivíduos soropositivos para o HIV e 28 soronegativos e submetidas ao método gold standard e a NPCR tendo como alvo o transposon IS6110. Resultados. A tuberculose foi diagnosticada em 11 pacientes (14,3%), com 54,5% de formas extrapulmonares e 45,5% pulmonares. A NPCR foi positiva em todos, enquanto a cultura em apenas cinco deles. A positividade da baciloscopia entre os espécimes clínicos foi de 9.2%. A cultura permitiu o isolamento de sete cepas de M. tuberculosis e duas do Complexo M. avium (8,25%). A positividade molecular foi descrita em 23,85% das amostras. O desempenho da NPCR frente a cultura, para amostras pulmonares (n=22) e extrapulmonares (n=83) foi similar (100% de sensibilidade e aproximadamente 83% de especificidade). A positividade pela NPCR foi significantemente maior que o isolamento por cultura entre as amostras extrapulmonares (p=0.0042). Conclusões. Os resultados obtidos sugerem a realização de estudos mais amplos que corroborem o potencial da NPCR-IS6110 para a detecção do genoma micobacteriano na TB extrapulmonar, em especial entre imunocomprometidos. Ademais, a detecção da micobactéria permanece como confirmação diagnóstica e a oportunidade de investigação do perfil de sensibilidade, favorecendo o tratamento efetivo para qualquer faixa etária e status imunológico.
4

Génétique humaine des formes cliniques de la lèpre / Human genetics of clinical forms of leprosy

Gaschignard, Jean 27 March 2015 (has links)
La lèpre est une maladie tropicale négligée qui atteint près de 200 000 personnes chaque année et dont l’agent causal est Mycobacterium leprae. La susceptibilité génétique de l’hôte à la maladie est bien établie, et a permis de comprendre certains mécanismes de la physiopathologie de la maladie. Il existe par ailleurs une grande variabilité inter-individuelle des manifestions cliniquesde la maladie, qui s’étendent d’un pôle dit tuberculoïde à un pôle dit lépromateux. Nous avons cherché à identifier les facteurs de susceptibilité génétique à cette polarisation de la maladie. Nous avons tout d’abord décrit que le sexe et l’âge sont des facteurs non-génétiques associés à ce phénotype.Notre travail s’est ensuite appuyé sur les outils classiques de l’épidémiologie génétique, c’est à dire les études de liaison et d’association, pour identifier des variants génétiques qui influencent la polarisation de la lèpre. Nous avons utilisé une puce à ADN pangénomique avec plus de 500 000 marqueurs pour génotyper un échantillon de familles vietnamiennes comprenant 939 malades, dont 692 enfants. Nous avons identifié une liaison de la région 19p12 avec la polarisation de la lèpre. L’étude d’association n’a pas permis d’identifier de signal significatif à l’échelle du génome. Nous avons développé un nouveau test d’association pour des données familiales qui a permis d’améliorer les résultats sans atteindre la significativité. Notre travail sera prolongé par des études d’association dans deux populations cas-témoins du Vietnam et du Brésil. Nous chercherons à identifier les marqueurs causaux au sein de la région de liaison 19p12 d’une part, et à découvrir de nouveaux variants d’autre part. L’identification de marqueurs associés à la polarisation de la lèpre permettra de mieux prévoir l’évolution de la maladie et de proposer des traitements plus ciblés selon le risque génétique individuel. / Leprosy is a neglected tropical disease that affects nearly 200,000 people each year and caused byMycobacterium leprae. Genetic host susceptibility to the disease is well established, and helped to understand some of the mechanisms of the disease’s physiopathology. There is also a wide inter-individual variability of the clinical manifestations of the disease, which runs from a so-said tuberculoid to a so-said lepromatous pole. We sought to identify genetic susceptibility factors for this polarization of the disease. We initially described gender and age as non-genetic factors associated with this phenotype. We then based our analysis on the classical tools from thefield of genetic epidemiology, namely linkage and association studies, to identify genetic variants that influence leprosy polarization. We used a DNA-microarray with 500,000 markers spanning over the whole genome to genotype a sample of Vietnamese families including 939 patients, of which 692 were children. We have found a region linked to leprosy polarization on chromosome 19p12. The association study could not identify a significant signal across the genome. We developed a new test for association designed for familial data that improved the results without reaching significance. Our work will be pursued by association studies in two case-control populations from Vietnam and Brazil. We will try to identify the causal markers within the 19p12 linkage region on the one hand, and to discover new variants on theother hand. The identification of markers associated with leprosy polarization could help us to better predict the evolution of the disease, and to offer more targeted treatments to patients, based on their individual genetic risk.

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