Central giant cell granuloma (CGCG) is an uncommon pathology of the maxillary bones, which has diverse clinical behavior. It can be treated either by surgical removal or by conservative methods such as systemic daily application of calcitonin and intralesional injections of corticosteroids. Recurrence of lesions seems to vary according to its clinical behavior, location and treatment modality. The aim of this study was to evaluate the recurrence rate of the CGCG of the jaws and its associated factors through a systematic review and meta-analyses. An electronic search in PubMed and Scopus databases was conducted in order to identify observational studies, published in English, that reported the recurrence rate of CGCG of the jaws regardless of treatment modality. In addition, a hand search of cross-references was also carried out identify additional studies. We excluded studies that did not report the main outcome of interest, with less than five cases and studies not available for full text review. Twenty-one studies, published between 1973 and 2011 met eligibility criteria and were included in this review. We observed a global recurrence rate of 13.4% (8.4%-19.1%, 95% CI). Surgical curettage showed the higher recurrence rate (15.8%, 10.7 – 21.7 95%CI), followed by calcitonin administration (9.7%, 0.0 – 31.8 95% CI) and surgical resection (0.16%, 0.0 – 0.07 95%CI). Lesion location was not associated with a higher risk of recurrence (RR = 1.7, 0.97 – 2.9, 95% CI). The results of this systematic review showed a high risk of lesion recurrence of aggressive CGCG treated with surgical curettage. / A lesão central de células gigantes (LCCG) é uma patologia incomum dos maxilares que apresenta comportamento clínico bastante variável. As modalidades terapêuticas para esta lesão variam desde tratamentos conservadores, com o uso de calcitonina e corticosteróides, a abordagens cirúrgicas mais radicais. As taxas de recidiva parecem variar de acordo com o comportamento clínico das lesões, tratamento indicado e localização. O objetivo deste trabalho foi, através de uma revisão sistemática com metanálise, avaliar as taxas de recidiva da LCCG dos maxilares e seus fatores associados. A revisão sistemática da literatura foi conduzida utilizando-se de busca eletrônica pelas bases de dados PubMed e Scopus. A lista de referências de todos os estudos elegíveis foi manualmente analisada para identificar estudos adicionais a serem incluídos. Foram incluídos estudos observacionais, publicados em língua inglesa, que relataram a taxa de recidiva da LCCG dos maxilares independente do tipo de tratamento realizado. Foram excluídos os estudos com menos de 5 casos, aqueles em que o desfecho de interesse não foi relatado e os artigos não disponíveis para leitura na íntegra. A heterogeneidade estatística entre os estudos foi analisada através do teste Q de Cochran e do índice I2 de Higgins e Thompson. As taxas de recidiva foram calculadas através de um modelo de efeitos randômicos após transformação do tipo Freeman-Tukey. O risco relativo para recidiva de acordo com comportamento clínico e localização das lesões foi calculado pelo método de Mantel-Haenszel. Foram incluídos 21 estudos observacionais, publicados entre 1973 e 2011. Foi observada uma taxa global de recidiva de 13.4% (IC 95% 8.4-19.1). Os pacientes tratados através de curetagem, ressecção cirúrgica e calcitonina tiveram taxas de recidiva de 15.8% (IC 95% 10.7-21.7), 0.16% (IC 95% 0.0-0.07) e 9.7% (0.0-31.8%), respectivamente. As lesões de comportamento agressivo tiveram um risco relativo para recidiva de 3.1 (IC 95% 1.7-5.7). Não foi observado aumento do risco em relação à localização da lesão (RR = 1.7; IC 95% 0.97-2.9). Desta forma, os resultados desta meta-análise indicam um risco elevado de recidiva em LCCG de comportamento agressivo e tratadas através de curetagem.

Ce travail de thèse a été axé sur l’étude de la réponse immunitaire T chez des patients atteints d’artérite à cellules géantes (ACG) et de pseudo-polyarthrite rhizomélique (PPR). Plusieurs études cliniques successives interrégionales ont permis d’inclure de nombreux patients (57 ACG et 27 PPR) des Centres Hospitaliers (CH) Universitaires et des CH de l’interrégion Est. Les échantillons sanguins ont été étudiés dans le laboratoire de l’unité INSERM U1098. Tout d’abord, nous avons confirmé l’implication des lymphocytes Th17 dans la pathogénie de l’ACG et avons montré pour la première fois leur implication au cours de la PPR. De plus, notre étude des lymphocytes T (LT) CD4+CD161+ a permis de mieux comprendre les mécanismes de plasticité entre les réponses Th1 et Th17 au cours de ces deux pathologies. Nous avons complété ces travaux par l’étude de la réponse T régulatrice en montrant qu’il existe un déficit quantitatif en Treg au cours de l’ACG et la PPR. Dans la suite de ce travail, nous avons mis en évidence, chez des patients atteints de polyarthrite rhumatoïde, que le blocage de la voie de signalisation de l’IL-6 par un anticorps monoclonal dirigé contre le récepteur de l’IL-6 permet de corriger le déséquilibre de la balance Th17/Treg, en diminuant la réponse Th17 et en augmentant simultanément la réponse T régulatrice, à l’inverse des corticoïdes qui diminuent le pourcentage de Th17 sans corriger le déficit en Treg. Enfin, dans la dernière partie de ce travail, nous avons montré pour la première fois que les LT CD8+ étaient également impliqués dans la pathogénie de l’ACG et la PPR. Ces résultats ont permis de progresser dans les connaissances physiopathologiques de l’ACG et la PPR en évoluant d’un modèle articulé autour d’un déséquilibre de la balance Th1/Th2 vers celui d’un déséquilibre de la balance Th17/Treg et permettent de proposer des thérapeutiques mieux ciblées pour l’ACG et la PPR. / The aim of this thesis was to investigate the T-cell immune response in the course of giant-cell arteritis (GCA) and polymyalgia rheumatica (PMR). Several studies conducted by our team allowed us to obtain blood samples from many patients affected by GCA (n=57) and PMR (n=28). Immunological studies were performed in INSERM U1098, University Of Burgundy, Dijon, France. We firstly demonstrated the implication of Th17 and CD4+CD161+ T cells in the pathogenesis of these two diseases, thus extending the knowledge in the plasticity mechanisms arising between Th1 and Th17 cell-immune responses in GCA and PMR. Furthermore, we investigated the regulatory T cell immune response in these two affections, demonstrating that although being functional, the percentage of circulating Treg was decreased in GCA and PMR patients. As interleukin-6 (IL-6) had been shown to control the Th17/Treg balance, we studied Th17 and Treg frequencies in rheumatoid arthritis patients treated with an anti-IL-6 receptor antibody (tocilizumab). We showed that the blockade of the IL-6 pathway was able to correct the Th17/Treg imbalance by decreasing the number of Th17 cells and simultaneously increasing that of Treg. Finally, we demonstrated for the first time the implication of CD8+ T cells in the pathogenesis of GCA and PMR. This thesis allowed us to progress in the knowledge of the pathogenesis of GCA making the pathogenesis model progress from a Th1/Th2 to a Th17/Treg imbalance model. Altogether, these data deciphering the immune response in the pathogenesis of GCA and PMR bring new knowledge which will lead to better targeted therapies.

Les nématodes à galles (RKN) du genre Meloidogyne spp. sont des parasites obligatoires des plantes qui induisent la formation d’un site nourricier spécialisé au sein des racines. Mon projet de thèse a pour objectif d’identifier des gènes spécifiques de ces nématodes qui sont impliqués dans le parasitisme en se focalisant sur des protéines sécrétées ou effecteurs. La technologie de séquençage Illumina a été utilisée pour comparer les transcriptomes de M. incognita au cours de son cycle de vie. A partir de 307 gènes surexprimés dans -au moins- un stade du cycle de vie, nous avons sélectionné 14 candidats d’effecteurs. Des expériences de RT-qPCR, d’hybridation in situ et d’ARN interférence ont permis de confirmer le profil d’expression, de localiser l’expression des effecteurs et d’étudier leur rôle dans la pathogénicité. Ce travail a permis de démontrer le rôle important d’une petite protéine, MiSCR1, dans les stades précoces du parasitisme. Parallèlement, nous avons réalisé l’assemblage de novo du transcriptome de M. enterolobii, qui représente une nouvelle menace pour l’agriculture mondiale du fait de sa capacité à se reproduire sur la majorité des plantes résistantes aux autres RKN. Les premières comparaisons avec d'autres RKN nous ont permis d'identifier, non seulement des effecteurs en commun, mais aussi ceux qui sont spécifiques à certaines espèces de RKN et qui pourraient expliquer des différences de gamme d'hôtes. En conclusion, les analyses de transcriptomes de RKN ont permis de caractériser des nouveaux effecteurs candidats impliqués dans la pathogénicité, et d’apporter de nouvelles connaissances pour le développement de méthodes de lutte contre ces bioagresseurs / Root-knot nematodes (RKN) are obligate endoparasites that maintain a biotrophic relationship with their hosts inducing specialized feeding cells. My PhD project aims to identify RKN genes specifically involved in plant parasitism with an emphasis on genes encoding new secreted proteins, named effectors. Using Illumina RNA-seq technologies, we compared transcriptomes of Meloidogyne incognita during its life cycle. From 307 genes over-expressed at -at least- one stage of the life cycle, we selected 14 effector candidates. RT-qPCR, in situ hybridisation and siRNA soaking experiments were carried out to confirm their expression profile, localize the spatial expression of these candidates in the nematode and to study their role in pathogenicity. The silencing of the dorsal gland specific-Minc18876 gene and its paralogues resulted in a significant, reproducible decrease in the number of egg masses, demonstrating a potentially important role for the small cysteine-rich effector, MiSCR1, it encodes in early stages of giant cell formation. In parallel, we perform a de novo assembly of M. enterolobii transcriptome. This RKN species represents a new threat for the agriculture worldwide because of its ability to reproduce on the majority of known RKN-resistant plants. First comparisons with others RKN allowed us to identify, not only the common set of effectors, but also those specific to some RKN species and possibly involved in host range differences. In conclusion, the transcriptome profiling of RKNs allowed the characterisation of new candidate effectors involved in the plant pathogenicity, and provided a better knowledge for the development of new methods to control these pests

No description available.

No description available.

A realização de um diagnóstico envolve várias etapas, dentre elas o exame radiográfico. Embora a experiência do profissional seja fundamental, é necessário que o mesmo se atualize constantemente, conhecendo as novas tecnologias e de que forma a era digital vem se incorporando nas mais diferentes áreas. Neste trabalho buscou-se avaliar se a tecnologia digital pode colaborar na elaboração de hipóteses diagnósticas de lesões ósseas. Para isso, foram selecionadas 24 radiografias panorâmicas nas quais existiam imagens de lesões do tipo ameloblastoma, tumor odontogênico queratocístico, mixoma e lesão central de células gigantes, atestadas por laudos anátomo-patológicos. As radiografias foram digitalizadas e entregues a 12 examinadores, sendo 3 profissionais para cada uma de 4 diferentes especialidades (radiologia, estomatologia, patologia e cirurgia buco-maxilo-facial). Os examinadores observaram as imagens em dois momentos diferentes. Primeiramente analisaram a radiografia convencional e depois a imagem digitalizada correspondente com intervalo mínimo de 30 dias. Quando do exame das imagens digitais, foi oferecida aos examinadores a opção de uso de ferramentas disponíveis no software, que pudessem auxiliá-lo no procedimento. As suas opiniões eram anotadas em formulários, cujos dados foram posteriormente tabulados e submetidos à análise estatística, por meio de equações de estimação generalizadas (EEG) e índice kappa. Os resultados possibilitaram concluir que houve equivalência na eficácia dos dois métodos avaliados, com boa concordância entre os diagnósticos dos especialistas, e que a probabilidade de acerto não depende da especialidade do observador e nem do tipo de lesão. O método digital foi o preferido para observação entre os avaliadores, sendo que a ferramenta brilho e contraste foi considerada como a melhor auxiliar na elaboração das hipóteses diagnósticas, não havendo uma padronização de valores para tal. Os resultados sugerem ainda que as ferramentas da análise digital favoreceram mais o diagnóstico de um determinado tipo de lesão em comparação aos outros. / The achievement of a diagnosis includes several steps, among them, the radiographic exam. Although the professional experience is fundamental, it is necessary that the professional has been updated constantly, learning new technologies and how the digital era has been incorporated to different areas of knowledge. This work aimed to assess if the digital technology might play a role in the elaboration of diagnostic hypothesis of bone lesions. For that, it was selected 24 panoramic radiographs in which it was possible to observe lesion images of ameloblastoma, keratinizing cystic odontogenic tumor, odontogenic myxoma and central giant cell lesion, with histophatological diagnosis. The radiographs were digitalized and delivered to 12 examiners, being 3 professionals for each one of the 4 specialties (radiology, stomatology, pathology and oral surgery). The examiners have observed the images in two different situations. First they analyzed the conventional radiography and then the corresponding digitalized images, after at least 30 days long. Joined to the digitalized images, it was provided to the examiners software facilities in order to support them in the procedures. Their opinions were filled in booking forms, whose information were tabulated and submitted to statistical analysis through generalized estimation equations (EEG) and kappa index. The outcome has indicated that there was an equivalent fficiency between the two selected methods of assessment. There was a good match of the diagnosis made by the examiners from each speciality, and the probability of a right judgment did not rely on the observer specialty nor on the type of lesion. The examiners have preferred the digital method, and the digital tools bright and contrast were considered the best support for the elaboration of diagnostic hypothesis. Moreover, it was not obtained standard values for bright or contrast. The outcome of this work also suggests that the use of digital analysis tools tends to be more effective for a specific type of lesion than others.

A realização de um diagnóstico envolve várias etapas, dentre elas o exame radiográfico. Embora a experiência do profissional seja fundamental, é necessário que o mesmo se atualize constantemente, conhecendo as novas tecnologias e de que forma a era digital vem se incorporando nas mais diferentes áreas. Neste trabalho buscou-se avaliar se a tecnologia digital pode colaborar na elaboração de hipóteses diagnósticas de lesões ósseas. Para isso, foram selecionadas 24 radiografias panorâmicas nas quais existiam imagens de lesões do tipo ameloblastoma, tumor odontogênico queratocístico, mixoma e lesão central de células gigantes, atestadas por laudos anátomo-patológicos. As radiografias foram digitalizadas e entregues a 12 examinadores, sendo 3 profissionais para cada uma de 4 diferentes especialidades (radiologia, estomatologia, patologia e cirurgia buco-maxilo-facial). Os examinadores observaram as imagens em dois momentos diferentes. Primeiramente analisaram a radiografia convencional e depois a imagem digitalizada correspondente com intervalo mínimo de 30 dias. Quando do exame das imagens digitais, foi oferecida aos examinadores a opção de uso de ferramentas disponíveis no software, que pudessem auxiliá-lo no procedimento. As suas opiniões eram anotadas em formulários, cujos dados foram posteriormente tabulados e submetidos à análise estatística, por meio de equações de estimação generalizadas (EEG) e índice kappa. Os resultados possibilitaram concluir que houve equivalência na eficácia dos dois métodos avaliados, com boa concordância entre os diagnósticos dos especialistas, e que a probabilidade de acerto não depende da especialidade do observador e nem do tipo de lesão. O método digital foi o preferido para observação entre os avaliadores, sendo que a ferramenta brilho e contraste foi considerada como a melhor auxiliar na elaboração das hipóteses diagnósticas, não havendo uma padronização de valores para tal. Os resultados sugerem ainda que as ferramentas da análise digital favoreceram mais o diagnóstico de um determinado tipo de lesão em comparação aos outros. / The achievement of a diagnosis includes several steps, among them, the radiographic exam. Although the professional experience is fundamental, it is necessary that the professional has been updated constantly, learning new technologies and how the digital era has been incorporated to different areas of knowledge. This work aimed to assess if the digital technology might play a role in the elaboration of diagnostic hypothesis of bone lesions. For that, it was selected 24 panoramic radiographs in which it was possible to observe lesion images of ameloblastoma, keratinizing cystic odontogenic tumor, odontogenic myxoma and central giant cell lesion, with histophatological diagnosis. The radiographs were digitalized and delivered to 12 examiners, being 3 professionals for each one of the 4 specialties (radiology, stomatology, pathology and oral surgery). The examiners have observed the images in two different situations. First they analyzed the conventional radiography and then the corresponding digitalized images, after at least 30 days long. Joined to the digitalized images, it was provided to the examiners software facilities in order to support them in the procedures. Their opinions were filled in booking forms, whose information were tabulated and submitted to statistical analysis through generalized estimation equations (EEG) and kappa index. The outcome has indicated that there was an equivalent fficiency between the two selected methods of assessment. There was a good match of the diagnosis made by the examiners from each speciality, and the probability of a right judgment did not rely on the observer specialty nor on the type of lesion. The examiners have preferred the digital method, and the digital tools bright and contrast were considered the best support for the elaboration of diagnostic hypothesis. Moreover, it was not obtained standard values for bright or contrast. The outcome of this work also suggests that the use of digital analysis tools tends to be more effective for a specific type of lesion than others.

Made available in DSpace on 2014-12-17T15:32:16Z (GMT). No. of bitstreams: 1 PedroPAS.pdf: 6126862 bytes, checksum: 3ae3ec2483d9e09d3a05fcd73782e862 (MD5) Previous issue date: 2008-02-27 / Conselho Nacional de Desenvolvimento Cient?fico e Tecnol?gico / The giant cell fibroma is a benign neoplasm characterized by the presence of mono, bi or multinucleate cells, which can have a connection to the presence of mast cells. This research aims to analyze, descriptively and comparatively, the immunohystochemistry expression of the tryptase in mast cells of the giant cell f ibroma, f ibrous hyperplasia and samples of the normal oral mucosa. Thirty cases of giant cell fibroma, ten cases of fibrous hyperplasia and ten cases of normal oral mucosa were selected for the analysis of the immunohistochemistry expression, determination of the number of present mast cells, as well as their location and shape. It could be stated that there was a statistically signif icant difference (p<0,001) in relation to the quantity of mast cells among other samples analyzed where the giant cell f ibroma presented lesser quantity of mast cell and the hyperplasia showed higher concentration of this cellular type. Although the oral mucosa has presented a higher quantity of mast cells when compared to the giant cells fibroma, these were found in usual locations in the connective tissue in normal tissues. There could be noticed a statistically significant difference in relation to the number of non-granulated mast cells (p<0,001). On the areas of fibrosis, we could observe a statistically signif icant difference (p<0,006) among the samples. In relation to the present mast cells in perivascular location, no statistically signif icant difference was found. On the morphological analysis there was a predominance of oval mast cells. It was concluded that despite of the fact there was a lesser quantity of mast cells present in cases of giant cell f ibroma, they appeared to have a stronger relation to the present giant fibroblasts in this lesions, around 59,62%, being also evidenced a strong relation between these cells and the fibrosis areas in both cases of giant cell f ibroma and f ibrous hyperplasias and samples of normal oral mucosa, used as control group in our study, confirming, this way, the role of the mast cells as fibrinogenous inductor / O fibroma de c?lulas gigantes constitui-se de uma neoplasia benigna, caracterizada pela presen?a de c?lulas gigantes, mono, bi ou multinucleadas, c?lulas estas que podem guardar rela??o com a presen?a de mast?citos. O prop?sito desta pesquisa consistiu em analisar descritiva e comparativamente a express?o imuno-histoqu?mica da triptase em mast?citos de fibroma de c?lulas gigantes, hiperplasia fibrosa e esp?cimes de mucosa oral normal. Foram selecionados 30 casos de fibroma de c?lulas gigantes, 10 casos de hiperplasia fibrosa e 10 casos de mucosa oral normal, para a an?lise da express?o imuno-histoqu?mica, determina??o do n?mero de mast?citos presentes, bem como a sua forma e localiza??o. Constatou-se diferen?a estatisticamente significativa (p<0,001) em rela??o a quantidade de mast?citos entre os esp?cimes analisados, onde o fibroma de c?lulas gigantes apresentou a menor quantidade de mast?citos e a hiperplasia exibiu a maior concentra??o deste tipo celular. Embora a mucosa oral tenha apresentado uma maior quantidade de mast?citos quando comparado com os casos de f ibroma de c?lulas gigantes, estes se encontravam em localiza??es usuais no tecido conjuntivo em tecidos normais. Verif icou-se, diferen?a estatisticamente significativa, no que diz respeito ao n?mero de mast?citos n?o degranulados (p<0,001). Nas ?reas de fibrose, observamos diferen?a estatisticamente signif icativa (p<0,006) entre os esp?cimes. Com rela??o aos mast?citos presentes em localiza??o perivascular n?o se observou diferen?a estatisticamente significativa. Na an?lise morfol?gica verif icou-se uma predomin?ncia de mast?citos ovais. Concluiu-se que embora uma menor quantidade de mast?citos estivesse presente nos casos de fibroma de c?lulas gigantes, estes exibiam maior rela??o com os fibroblastos gigantes presentes nestas les?es em torno de 59,62%, sendo evidenciada tamb?m uma forte rela??o entre estas c?lulas e ?reas de fibrose tanto nos casos de fibroma de c?lulas gigantes como de hiperplasias fibrosas e esp?cimes de mucosa oral normal, utilizados como controle em nosso estudo, confirmando desta forma, o papel dos mast?citos como indutor fibrinog?nico

Submitted by Luciana Ferreira (lucgeral@gmail.com) on 2015-12-10T09:47:46Z No. of bitstreams: 2 Dissertação - Allison Filipe Lopes Martins - 2015.pdf: 3205167 bytes, checksum: 5c24397e18241a8a809af753bb233428 (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) / Approved for entry into archive by Luciana Ferreira (lucgeral@gmail.com) on 2015-12-10T10:03:57Z (GMT) No. of bitstreams: 2 Dissertação - Allison Filipe Lopes Martins - 2015.pdf: 3205167 bytes, checksum: 5c24397e18241a8a809af753bb233428 (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) / Made available in DSpace on 2015-12-10T10:03:57Z (GMT). No. of bitstreams: 2 Dissertação - Allison Filipe Lopes Martins - 2015.pdf: 3205167 bytes, checksum: 5c24397e18241a8a809af753bb233428 (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) Previous issue date: 2015-03-27 / Conselho Nacional de Pesquisa e Desenvolvimento Científico e Tecnológico - CNPq / The Central Giant Cell Lesion (CGCL) is an intraosseous lesion that can be classified into non aggressive and aggressive. Due to the aesthetic and functional defects of surgical treatment of CGCL, therapies with drugs have been reported, such as glucocorticoid injections and calcitonin. The studies reported in the literature support the use of these drugs through the investigation of the presence of glucocorticoid receptors (RGC) and calcitonin (RCT) in CGCL; however there is no consensus if all lesions express these receptors and if there is any difference between non aggressive and aggressive lesion. In addition, there are no studies that evaluated the bone formation potential through the investigation of Osteocalcin (OC) in aggressive and non-aggressive lesions. The aim of this study was to compare, using immunohistochemistry, the GR and CTR and osteocalcin protein (OC) expression in non aggressive (n = 20) and aggressive (n = 11) CGCL, and the correlation between the OC expression and these receptors determined in both groups of lesions. The number of mononuclear cells in mitosis (MOC), and the number of multinucleated giant cells (MGC) were also investigated using immunohistochemical techniques (hematoxylin and eosin). Our results show that all the cases express the GR and CTR and that there is no difference in the expression of these receptors or the number of mitosis between non aggressive and aggressive lesions. The OC expression was rare and higher in non aggressive lesions, however, not statistically significant (p> 0.05). There was a correlation between the CTR expression in MOC and MGC (r = 0.45; p <0.01). Considering the different variants of CGCL, there was a correlation between CTR expression in MOC and MGC in non aggressive lesions (r = 0.66; p <0.01) and between the CTR and OC expression in MGC (r = 0.718; p = 0.01). There was a higher number of MGC in aggressive lesions (p = 0.01). The results indicate that all cases express GR and CTR and that there are no differences between non aggressive and aggressive CGCL lesions of these receptors expression, these results strengthens CGCL treatment with glucocorticoids and calcitonin. Aggressive lesions have a higher number of MGC. The CGCL express glucocorticoid and calcitonin receptors and this finding give biological basis to the CGCL treatment with intralesional glucocorticoid and calcitonin either in non aggressive and aggressive cases. It was also identified osteocalcin positive cells, that may be related to bone repair, it is believed that these cells may also serve as a therapeutic target. / A Lesão Central de Células Gigantes (LCCG) é uma lesão intraóssea que pode ser classificada em não agressiva e agressiva. Devido aos defeitos estéticos e funcionais do tratamento cirúrgico da LCCG, terapias medicamentosas tem sido relatadas, como injeções de glicocorticoide e calcitonina. Há na literatura estudos que suportam o uso desses medicamentos através da investigação da presença de receptores de glicocorticoides (RGC) e de calcitonina (RCT) em LCCG. No entanto não existe consenso se todas as LCCG expressam esses receptores e se existe alguma diferença entre lesões agressivas e não agressivas. Além disso, não existem estudos sobre a avaliação do potencial de formação óssea através da Osteocalcina (OC) em lesões agressivas e não agressivas. O propósito deste estudo foi avaliar comparativamente, por meio de imunohistoquímica, a expressão de RGC e RCT e da OC em LCCG não agressivas (n= 20) e agressivas (n= 11) e a correlação entre a expressão da OC e desses receptores nos dois grupos de lesões estudados. O número de mitoses nas células mononucleares e o número de células gigantes multinucleadas também foram investigados, utilizando técnica histoquímica (hematoxilina e eosina). Nossos resultados mostram que todos os casos analisados expressam o RGC e RCT e que não existe diferença na expressão do RGC, RCT ou do número de mitoses entre lesões não agressivas e agressivas. A expressão de OC em células mononucleares foi rara e maior em lesões não agressivas, no entanto, sem diferenças estatisticamente significantes (p>0,05). Houve correlação entre a expressão do RCT em células mononucleares e células gigantes multinucleadas (r=0,45; p<0,01). Considerando as diferentes variantes foi verificada correlação do RCT entre o componente mononuclear e as células gigantes multinucleadas nas lesões não agressivas (r=0,66; p<0,01) e entre a expressão de OC e RCT em células gigantes multinucleadas (r= 0,718; p=0,01). Houve maior número de células gigantes em lesões agressivas (p= 0,01). Os resultados indicam que todos os casos expressam RGC e RCT e que não há diferenças entre lesões agressivas e não agressivas de LCCG quanto à expressão desses receptores, fortalecendo a recomendação o tratamento da LCCG com o uso de glicocorticoide e calcitonina. Lesões agressivas apresentam maior número de CGM. As células da LCCG expressam o RGC e RCT e esse achado pode fornecer bases biológicas para o tratamento com injeções intralesionais de glicocorticoides e o uso de calcitonina, seja em lesões não agressivas ou agressivas. Adicionalmente, foram identificadas células expressando OC, que podem estar relacionadas ao reparo ósseo, acredita-se que essa linhagem celular também pode se tornar um alvo terapêutico.

Rationnel : L’artérite à cellules géantes (ACG) est une vascularite primitive des gros vaisseaux dont le diagnostic repose sur la mise en évidence d’un infiltrat inflammatoire et de cellules géantes à la biopsie d’artère temporale (BAT). On note également un remodelage de la paroi vasculaire lié à une prolifération des cellules musculaires lisses vasculaires (CMLV) pouvant aboutir à une occlusion artérielle. Objectif : Caractériser les auto-anticorps dirigés contre les cellules endothéliales (CE) et les CMLV au cours de l’ACG et préciser le rôle des CMLV dans le remodelage pariétal. Méthodes : La recherche d’auto-anticorps a reposé sur un immunoblot 2D couplé à la spectrométrie de masse. Les protéomes des CMLV d’artère ombilicale, d’artère pulmonaire et d’aorte humaines normales a été comparés par protéomique différentielle (2D-DIGE). Nous avons utilisé la 2D-DIGE et des puces d’expression pan-génomiques pour comparer les CMLV issues de BAT de patients suspects d’ACG (avec un diagnostic final d’ACG ou non), afin d’identifier les mécanismes contribuant à la prolifération des CMLV. Résultats : Chez 15 patients atteints d’ACG, nous avons notamment identifié la lamine, la vinculine et l’annexine A5 comme cible des auto-anticorps anti-CMLV. Les antigènes cibles identifiés sont liés à Grb2, une protéine adaptatrice impliquée dans la prolifération des CMLV. Nous avons mis en évidence des protéomes différents au sein des CMLV humaines normales selon leur origine vasculaire et avons principalement identifié des protéines du cytosquelette et du métabolisme énergétique.A partir des CMLV isolées des BAT et à l’aide d’Ingenuity®, nous avons identifié l’endothéline 1 (ET-1) et la paxilline comme des molécules impliquées dans le remodelage vasculaire. En immunohistochimie et par qPCR, nous avons confirmé l’expression de l’ET-1 et de ses récepteurs ETAR et ETBR au sein des artères temporales de patients atteints d’ACG. Enfin, nous avons inhibé la prolifération des CMLV avec du macitentan, un inhibiteur d’ETAR et en particulier avec son métabolite actif, mais pas avec d’autres inhibiteurs des récepteurs de l’ET-1. Conclusion : Nous avons identifié chez les patients atteints d’ACG des anticorps anti-CMLV dont le rôle pathogéne potentiel reste à définir. Les différences protéiques observées à partir des CMLV humaines normales pourraient correspondre à des phénotypes différents. A partir d’un matériel biologique unique, nous avons pu montrer que la prolifération excessive des CMLV au cours de l’ACG pouvait être inhibée par le macitentan ce qui permet d’envisager un usage thérapeutique de cette molécule. / Background : Giant cell arteritis (GCA) is a large vessel vasculitis and its diagnosis usually relies on the identification of an inflammatory infiltrate made of mononuclear cells and giant cells upon temporal artery biopsy. There is also a remodeling process in the arterial wall due to an excessive proliferation of vascular smooth muscle cells (VSMC) which can sometimes lead to arterial occlusion. Purpose: Identify auto-antibodies targeting either endothelial cells (EC) and/or VSMC during GCA and better understand the role of VSMC in the remodeling process. Methods : Auto-antibodies were detected by a 2-dimensionnal immunoblot and their target antigens were identified by mass spectrometry. Proteoms of umbilical artery, pulmonary artery and aorta VSMC were compared by 2 dimension differential in gel electrophoresis (2D-DIGE). In order to identify mechanisms involved in VSMC proliferation in GCA, we used both 2D-DIGE and pan genomic chips in order to compare VSMC isolated at the time of temporal artery biopsy (TAB) from patients with a final diagnosis of GCA or another diagnosis. Results : In 15 patients with GCA, we identified lamin, vinculin and Annexin A5 as target antigens of anti-VSMC antibodies. Target antigens were linked with Grb2, an adaptator protein involved in VSMC proliferation. Normal VSMC originating from different vascular beds have differ in protein contents with differential expression of cytoskeleton and energy metabolism proteins. We compared VSMC from TAB with Ingenuity software and identified endothelin-1 (ET-1) and paxillin as proteins involved in vessel remodeling. We confirmed by immunohistichemistry and qPCR that ET-1 and its receptor ETAR and ETBR were expressed in temporal arteries from patients with GCA. Last, we reduced VSMC proliferation with Macitentan, an ETAR and ETBR antagonist and significantly inhibited VSMC proliferation with its active metabolite whereas other ET-1 inhibitors had no effect. Conclusion : We identified anti-VSMC auto-antibodies in patients with GCA. Their pathogenic role remains to be determined. Normal VSMC from different vascular locations differ in protein conten which might reflect different phenotypes and different properties. The escessive proliferation of VSMC from patients with GCA was inhibited by Macitentan. This drug might constitute a future therapeutic option.