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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.
211

Mechanism of IL-12 Mediated Enhancement of Passive Experimental Autoimmune Myasthenia Gravis

Brown, Paul Michael January 2010 (has links)
No description available.
212

« Therapeutic Inducers of Natural Killer cell Killing » : une nouvelle thérapie cellulaire adoptive sécuritaire dans le contexte de la greffe allogénique de cellules souches hématopoïétiques

Poirier, Nicolas 12 1900 (has links)
Malgré les progrès en matière de greffe de cellules souches hématopoïétique (GCSH), environ 40% des enfants atteints d’une leucémie aigüe lymphoblastique (LAL) réfractaire à la chimiothérapie ne peuvent être guéris. Notre laboratoire a démontré que l’effet précoce de greffe contre leucémie (GvL) est significativement augmenté par les cellules Natural Killer (NK) stimulées par des cellules plasmacytoïdes dendritiques (pDC). Une nouvelle thérapie cellulaire adoptive basée sur la stimulation des cellules NK par les pDC a été développée et son efficacité a été démontrée dans un modèle de souris humanisées. Des cellules hautement spécialisées appelées « Therapeutic Inducers of Natural Killer cell Killing » (ThINKK), analogues des pDC, sont produites à partir de cellules souches hématopoïétiques de sang de cordon. Afin d’amener les ThINKK vers un usage clinique, ce projet avait comme objectif d’en compléter la caractérisation, d’investiguer leurs effets secondaires potentiels après transfert adoptif dans le contexte de transplantation hématopoïétique allogénique et d’évaluer l’impact d’un régime prophylactique immunosuppresseur sur l’axe ThINKK/cellules NK. L’identité cellulaire des ThINKK a été déterminée par cytométrie de flux et par analyse unicellulaire du transcriptome (scRNA-seq). Pour déterminer si la présence des ThINKK pourrait augmenter l’activation et la prolifération des cellules T allogéniques, nous avons utilisé des réactions lymphocytaires mixtes (MLR) dans lesquelles les cellules T et les ThINKK ont été cultivées en présence de cellules présentatrices d’antigènes. Un modèle murin de réaction de greffe contre l’hôte (xéno-GvHD) nous a permis de déterminer l’impact du transfert adoptif de ThINKK sur la GvHD in vivo. Finalement, nous avons testé l’effet d’immunosuppresseurs sur la cytotoxicité des cellules NK activées par ThINKK contre des cellules LAL. Nos résultats démontrent que les ThINKK n’expriment pas les marqueurs associés aux cellules présentatrices d’antigènes, mais expriment les marqueurs des cellules plasmacytoïdes dendritiques. L’analyse des résultats de scRNA-seq démontre la présence d’une sous-population cellulaire mineure exprimant le récepteur AXL, sans toutefois exprimer les autres marqueurs conventionnels des cellules présentatrices d’antigènes. Les ThINKK, incluant la sous-population AXL-positive, n’exacerbent pas l’activation ou la prolifération des cellules T allogéniques in vitro ou in vivo. Finalement, des cinq immunosuppresseurs testés, seules la cyclosporine A et de la méthylprednisolone diminuaient l’activation et la cytotoxicité des cellules NK induites par les ThINKK. Nos résultats suggèrent qu’une immunothérapie par transfert adoptif de ThINKK serait sécuritaire chez les patients ayant reçu une greffe allogénique. L’utilisation d’un régime prophylactique immunosuppresseur est également possible sans affecter l’efficacité de cette nouvelle immunothérapie post-transplantation. / The survival outcomes of children with relapsed acute lymphoblastic leukemia (ALL) remain dismal despite progress in hematopoietic stem cell transplantation. In the past, our team has demonstrated that the stimulation of Natural Killer (NK) cells with a subset of plasmacitoid dendritic cells (pDCs) called Therapeutic Inducers of Natural Killer cell Killing (ThINKK) improved the early graft-versus-leukemia effect and controlled ALL development in humanized mice. ThINKK are expanded from cord blood hematopoietic stem cell progenitors for adoptive post-transplant immunotherapy. To translate these findings into the clinic, the main objectives of this project was to further characterize the ThINKK phenotype, to investigate the potential adverse effects of ThINKK in the context of allogeneic hematopoietic transplantation, and to evaluate the functional impact of the post-transplant prophylactic immunosuppressive regimen on the ThINKK/NK cell axis. The cellular identity of ThINKK was assessed using flow cytometry and single-cell RNA sequencing. To assess the potential exacerbation of T-cell activation and proliferation by ThINKK, allogeneic T cells and ThINKK were co-cultured with or without antigen-presenting cells in mixed lymphocyte reactions (MLR). We used a xenograft mouse model to evaluate the efficacy and potential side effects of an adoptive transfer of ThINKK on graft-versus-host reactions in vivo. Finally, we tested the effect of immunosuppressive drugs on ThINKK-induced NK cell cytotoxicity against ALL cells. We found that ThINKK cells did not express antigen-presenting cell markers but expressed pDCs lineage markers. Single-cell RNA sequencing analysis revealed the presence of a minor cell subset expressing the AXL receptor gene, but lacking expression of other conventional dendritic cell marker genes. Importantly, ThINKK including the AXL+ subset did not exacerbate allogeneic T-cell activation and proliferation in vitro and in vivo. Finally, out of the five immunosuppressive drugs tested, only cyclosporine A and methylprednisolone decreased ThINKK-induced NK cell activation and cytotoxicity. Our results support that ThINKK cell transfer immunotherapy could be safe in transplanted subjects even in allogeneic settings and that a prophylactic immunosuppressive regimen may be used without affecting the efficacy of this novel post-transplant immunotherapy.
213

Characterizing the role of Nucleosome Remodeling Factor (NURF) in tumorigenesis and metastatic progression using mouse models of breast cancer.

Alkhatib, Suehyb 20 June 2012 (has links)
Increasingly the role of epigenetic machinery as a bridge between underlying DNA sequence and cellular phenotype is being discovered. The establishment of a myriad of unique cellular types sharing identical gene sequences in a multicellular organism gives a broad sense for the inherent role of epigenetic influence on cell differentiation. Importantly, the epigenetic mechanisms involved in establishing cell identity unsurprisingly contribute to diseased states, including cancer. Recent research continues to elucidate contributory roles of epigenetic mechanisms, such as DNA methylation, histone modification, and microRNA regulation, in human cancers. Additionally, chromatin remodelers, such as the Nucleosome Remodeling Factor (NURF), have been identified as important regulators for normal cell biology. While much has been done to identify and characterize the role of NURF chromatin remodeling complex as a key regulator of development in a number of model organisms, little has been published on the implications of NURF in diseases such as cancer. Our preliminary data shows dysregulation of E-cadherins, N-cadherins, and MHC-I genes in Bptf (an essential subunit of NURF) knocked down murine breast cancer cell lines. These proteins have well documented roles in the development and metastatic progression of cancers. To study the effect of Bptf knockdown on the development and progression of cancer we injected Bptf knocked down mouse breast cancer cell lines, 4T1, 66cl4, and 67NR, into syngenic BALB/c mice. Our findings reveal decreased tumor growth in 66cl4 and 67NR as measured by tumor weight at 3-4 weeks post injection. Tumor growth did not appear to be significantly affected in 4T1 challenged mice. However, mice inoculated with Bptf knockdown 4T1 cell lines have decreased metastasis to lungs as compared to control while metastasis of 66cl4 tumors to the lungs appear unaffected. To assess the role of the immune system in decreasing tumor growth in BALB/c mice, we injected 66cl4 tumors into NOD-SCID-Gamma (NSG) immune deficient mice. The tumors from these mice show no difference in tumor growth between Bptf knockdown and control tumors, implicating a role for the immune system regulating the decreased tumor weight in BALB/c mice. To delineate which immune cell effector may impede breast cancer carcinogenesis, we performed an in vitro natural killer (NK) cell cytotoxicity assay against 66cl4 tumors and found greater susceptibility to NK killing in Bptf knockdown tumors.
214

Avaliação das células iNKT em pacientes com endometriose / Evaluation of iNKT cells in patients with endometriosis

Correa, Frederico José Silva 23 November 2018 (has links)
Introdução: A endometriose é uma doença com características inflamatórias que atinge as mulheres em idade reprodutiva. A patogênese da endometriose não está esclarecida. Tem sido demonstrada associação entre distúrbios imunológicos e endometriose, como alterações nos macrófagos, células NK, citocinas e nas repostas Th1, Th2 e Th17. As células iNKT, um tipo especial de linfócitos T, tem importante papel na resposta inflamatória como mediadores das repostas Th1, Th2 e Th17. Objetivos: o objetivo principal deste estudo foi comparar as frequências das células iNKT e seus subtipos entre pacientes com endometriose e pacientes sem endometriose. Procuramos também comparar as frequências destas células em ambos os grupos relacionando com alguns os aspectos clínicos e cirúrgicos da doença. Métodos: Realizamos estudo transversal, prospectivo entre fevereiro de 2013 a fevereiro de 2015 que avaliou a porcentagem de células iNKT e os subtipos iNKT CD4+, iNKT CD4+ CCR7+, iNKT CD4+ CD25+, iNKT DN, iNKT DN CCR7+, iNKT DN CD25+, iNKT CD4+ IL6+, iNKT CD4+ IL10+, iNKT CD4+ IL17+, iNKT CD8+ IL6+, iNKT CD8+ IL10+, iNKT CD8+ IL17+, iNKT DN IL6+, iNKT DN IL10+, iNKT DN IL17+ no sangue periférico, por citometria de fluxo, em pacientes com endometriose profunda (n = 47) e sem endometriose (n = 26). As frequências de células iNKT e seus subtipos foram comparadas entre os grupos de acordo com os sintomas, fase do ciclo, estádio da doença e classificação histológica. Resultados: Na avaliação da frequência das células iNKT, iNKT DN e iNKT DN IL17+ foi evidenciada diminuição significativa nas pacientes com endometriose (p=0,010, p=0,020, p=0,050; respectivamente). Além disso, foi observada diminuição significativa nas frequências das células iNKT CD4+ CCR7+ e aumento significativo das células iNKT CD4+ IL-17+ em pacientes com endometriose e dismenorréia severa em comparação a dismenorréia ausente/leve. Nas pacientes com endometriose e dor acíclica severa observou-se diminuição significativa da frequência das células iNKT CD4+ IL17+ em comparação a dor acíclica ausente/leve (p=0,048). Houve diminuição das células iNKT nas pacientes com endometriose em relação ao grupo controle na fase secretora do ciclo menstrual (p=0,030). Na avaliação da fase do ciclo menstrual foi observado na fase proliferativa aumento significativo na frequência das células iNKT CD4+ CD25+ (p=0,022) e diminuição significativa das células iNKT DN (p=0,011) nas pacientes com endometriose. Na fase secretora foi evidenciado diminuição significativa na frequência das células iNKT DN IL17+ (p=0,049) nas pacientes com endometriose. Foi identificado também nas pacientes com endometriose uma diminuição na frequência das células iNKT DN CD25+ na fase secretora em relação a fase proliferativa do ciclo menstrual. Conclusões: As células iNKT e os subtipos iNKT DN e iNKT DN IL17+ se mostraram alteradas nas pacientes com endometriose profunda. Subtipos específicos de células iNKT estão alteradas nas pacientes com endometriose profunda em pacientes com dismenorréia e dor acíclica severas. As fases do ciclo menstrual estão relacionadas a alteração nas frequências das células iNKT e dos subtipos iNKT CD4+ CD25+, iNKT DN, iNKT DN IL17+ e iNKT DN CD25+ nas pacientes com endometriose profunda. Estes resultados sugerem participação das células iNKT no desenvolvimento da endometriose / Introduction: Endometriosis is a disease with inflammatory characteristics that affects women of reproductive age. The pathogenesis of endometriosis is unclear. There has been an association between immune disorders and endometriosis, such as changes in macrophages, NK cells, cytokines, and Th1, Th2 and Th17 responses. iNKT cells, a special type of T lymphocytes, play an important role in the inflammatory response as mediators of the Th1, Th2 and Th17 responses. Objectives: The main objective of this study was to compare the frequencies of iNKT cells and their subtypes between patients with endometriosis and patients without endometriosis. We also compare the frequencies of these cells in both groups relating to some clinical and surgical aspects of the disease. Methods: We performed a prospective cross-sectional study between February 2013 and February 2015, which evaluated the percentage of iNKT cells and iNKT CD4+, iNKT CD4+ CCR7+, iNKT CD4+ CD25+, iNKT DN, iNKT DN CCR7+, iNKT DN CD25+, iNKT CD4+ IL6+ , iNKT CD8+ IL17+, iNKT DN IL6+, iNKT DN IL10+, iNKT DN IL17+ in the peripheral blood, by flow cytometry, in patients with deep endometriosis (n = 47), iNKT CD4+ IL10+, iNKT CD4+ IL17+, iNKT CD8+ ) and without endometriosis (n = 26). The frequencies of iNKT cells and their subtypes were compared between groups according to symptoms, stage of the cycle, stage of the disease and histological classification. Results: iNKT, iNKT DN and iNKT DN IL17+ cells showed significant decrease in patients with endometriosis (p = 0.010, p = 0.020, p = 0.050, respectively). In addition, a significant decrease in iNKT CD4+ CCR7+ cell numbers and a significant increase of iNKT CD4+ IL17+ cells were observed in patients with endometriosis and severe dysmenorrhea compared to absent / mild dysmenorrhea. In patients with endometriosis and severe acyclic pain, there was a significant decrease in the frequency of iNKT CD4+ IL17+ cells compared to absent / mild acyclic pain (p = 0.048). There was a decrease in iNKT cells in patients with endometriosis compared to the control group in the secretory phase of the menstrual cycle (p = 0.030). In the menstrual cycle, a significant increase in iNKT CD4+ CD25+ cells (p = 0.022) and a significant decrease in iNKT DN cells (p = 0.011) was observed in the proliferative phase in patients with endometriosis. In the secretory phase there was a significant decrease in the frequency of iNKT DN IL17 + cells (p = 0.049) in patients with endometriosis. It was also identified in patients with endometriosis a decrease in the frequency of iNKT DN CD25+ cells in the secretory phase in relation to the proliferative phase of the menstrual cycle. Conclusions: iNKT cells and subtypes iNKT DN e iNKT DN IL17+ have been altered in patients with deep endometriosis. Specific subtypes of iNKT cells are altered in patients with deep endometriosis in patients with severe dysmenorrhea and acyclic pain. The phases of the menstrual cycle are related to changes in the frequencies of iNKT cells and subtypes iNKT CD4+ CD25+, iNKT DN, iNKT DN IL17+ and iNKT DN CD25+ in patients with deep endometriosis. These results suggest the participation of iNKT cells in the development of endometriosis
215

Mechanism and efficacy of a GD2-specific immunotherapy using NK cells

Seidel, Diana 27 February 2015 (has links)
Das Neuroblastom (NB) ist ein solider, extrakranieller Tumor neuroektodermalen Ursprungs, der sich im Kleinkindalter manifestiert. Ein etabliertes Zielantigen für die passive Immuntherapie beim NB ist das Disialogangliosid GD2. Aufgrund der geringen oder fehlenden Expression von MHC Klasse I Molekülen sowie der Tatsache, dass die Lyse von NB-Zellen durch verschiedene Mechanismen der natürlichen Zytotoxizität von NK-Zellen vermittelt werden kann, stellt eine auf NK-Zellen basierende Therapie einen vielversprechenden Ansatz zur Behandlung dieser Erkrankung dar. Auf dieser Grundlage wurde eine NK-Zelllinie generiert, die einen GD2-spezifischen chimären Antigenrezeptor (CAR) exprimiert (NK-92-scFv(ch14.18)-zeta). Die Hauptbestandteile dieses CARs sind ein Einzelkettenantikörper, welcher die variablen Regionen des GD2-spezifischen Antikörpers ch14.18 enthält, und die CD3ζ-Kette als signaltransduzierende Komponente. Im Rahmen dieser Arbeit konnte gezeigt werden, dass NK-92-scFv(ch14.18)-zeta in der Lage sind, auch Chemotherapie-resistente GD2-positive NB-Zelllinien effektiv abzutöten und dass dabei die Interaktion des CARs mit GD2 den Hauptmechanismus darstellt. Die anti-tumorale Wirkung von NK-92-scFv(ch14.18)-zeta in vivo wurde in einem Chemotherapie-resistenten GD2-positiven Xenograft-Mausmodell gezeigt. Die wiederholte Applikation von NK-92-scFv(ch14.18)-zeta in Kombination mit IL-2 resultierte in einem signifikant verlangsamten Tumorwachstum und einem verbesserten Überleben. Die Ergebnisse dieser Arbeit belegen, dass GD2-spezifische NK-92 das Potential für eine zukünftige klinische Anwendung besitzen. Demnach stellt der Einsatz einer solchen GD2-spezifischen NK-Zelllinie, die unter GMP-Bedingungen expandiert werden kann und zu jeder Zeit in einer standardisierten Qualität verfügbar wäre, eine vielversprechende Alternative zur Behandlung von Hochrisikopatienten dar, deren Erkrankung nicht mehr auf die Standardtherapie anspricht. / Neuroblastoma (NB) is a solid extracranial childhood malignancy of neuroectodermal origin. The Disialoganglioside GD2 is an established antigen for passive immunotherapy of NB. Cellular therapy of NB with natural killer (NK) cells is especially appealing because MHC class I expression is absent or low in most NB, rendering this tumor sensitive to NK cell recognition. Additionally, natural cytotoxicity of NK cells, mediated by interaction of activating NK cell receptors and their respective ligands on tumor cells, has been shown to play a role in lysis of NB cells. It is therefore tempting to assume that a combination of passive immunotherapy with GD2-specific antibodies and adoptive transfer of NK effector cells would result in an improved NB therapy. To achieve this goal an NK cell line expressing a GD2-specific chimeric antigen receptor (CAR) was engineered: NK-92-scFv(ch14.18)-zeta. This CAR consists of a GD2-specific scFv-fragment, which was generated from ch14.18, and the CD3ζ-chain as intracellular signal-transducing domain. Within this thesis, GD2-specificity of NK-92-scFv(ch14.18)-zeta as well as efficacy towards GD2-expressing NB cell lines, including relapse cell lines that exhibit partial or multidrug resistance were demonstrated. Blocking the interaction between the CAR and GD2 resulted in almost complete abrogation of NK-92-scFv(ch14.18)-zeta-mediated lysis of GD2-positive NB cell lines in vitro, indicating that this interaction is the main mechanism of activation of NK-92-scFv(ch14.18)-zeta. Importantly, repeated application of NK-92-scFv(ch14.18)-zeta in combination with IL-2 significantly decreased tumor growth and prolonged survival of mice in an aggressively growing drug-resistant xenograft NB mouse model. These findings suggest that GD2-specific NK-92 has potential for a future clinical application as NB-specific effector cells that would be ready on demand in a standardized quality.
216

Impact du G-CSF sur le phénotype et les fonctions des cellules NK dans le cadre d’une immunothérapie post-allogreffe de cellules souches hématopoïétiques / Impaired functions and proliferation of NK cells from patient G-CSF mobilized leukapheresis

Xiong, Yu 27 July 2016 (has links)
Les cellules Natural Killer (NK) sont capables de lyser les cellules tumorales sans la nécessité de reconnaitre un antigène tumoral spécifique. Cette propriété leur confère un avantage par rapport aux lymphocytes T et les rend intéressantes à utiliser en tant que cellules effectrices pour l’immunothérapie adoptive. A ce jour, le potentiel thérapeutique des cellules NK n’a pas été complétement exploré notamment dans le contexte du traitement de la rechute post-allogreffe de cellules souches hématopoïétiques. Actuellement, les patients en rechute post-greffe sont traités avec des injections de lymphocytes du donneur (DLI) parfois issues de petites fractions du greffon de cellules souches hématopoïétiques congelées. Les cellules souches périphériques étant fréquemment utilisées comme source de cellules souches et parfois utilisées comme DLI, nous avons souhaité évaluer l’impact du G-CSF sur le phénotype et les fonctions des cellules NK présentes dans ces fractions. Dans cet objectif, nous avons comparé différentes sources de cellules NK isolées à partir de sang de donneurs sains, de sang mobilisé de donneurs sains ou de patients et observé l’évolution des différentes sous-populations de cellules NK issues de ces prélèvements au décours d’une expansion en présence d’IL-15. Nos résultats ont montré que l’administration de G-CSF diminuait la proportion de cellules NK CD56brightCD16+ au profit d’une population CD16-, diminuait la prolifération des cellules NK lors de l’expansion en culture, et modifiait les propriétés fonctionnelles des cellules NK. / The ability of natural killer (NK) cells to kill tumor cells without the need to recognize a tumor-specific antigen provides advantages over T cells and makes them appealing for a use as effectors for adoptive immunotherapy. However, the full therapeutic potential of NK cell-based immunotherapy has not been fully investigated in the context of leukemic relapse after hematopoietic stem cell transplantation. Today, patients relapsing after hematopoietic stem cell transplantation are often treated with donor lymphocyte infusion (DLI) based on small cell fractions frozen at the time of the stem cell transplantation. Since peripheral blood stem cells are increasingly used as stem cell source and as source of cells for DLI, we aimed to evaluate the impact of G-SCF mobilization on NK cell phenotype and functions. Therefore, we compared the expansion capacity, the phenotype and the function of NK cells from blood for healthy donors, from allogeneic HSCT healthy donors or from autologous HSCT from patients. We also determine the impact of G-CSF on NK cell subset repartition before and after expansion in presence of IL-15. Our results showed that G-CSF administration to patients decreases CD56brightCD16+ NK cell population, proliferation and function. Overcoming this impairment in lymphoid capacity may be important to facilitate post-transplant immunotherapy.
217

Avaliação das células iNKT em pacientes com endometriose / Evaluation of iNKT cells in patients with endometriosis

Frederico José Silva Correa 23 November 2018 (has links)
Introdução: A endometriose é uma doença com características inflamatórias que atinge as mulheres em idade reprodutiva. A patogênese da endometriose não está esclarecida. Tem sido demonstrada associação entre distúrbios imunológicos e endometriose, como alterações nos macrófagos, células NK, citocinas e nas repostas Th1, Th2 e Th17. As células iNKT, um tipo especial de linfócitos T, tem importante papel na resposta inflamatória como mediadores das repostas Th1, Th2 e Th17. Objetivos: o objetivo principal deste estudo foi comparar as frequências das células iNKT e seus subtipos entre pacientes com endometriose e pacientes sem endometriose. Procuramos também comparar as frequências destas células em ambos os grupos relacionando com alguns os aspectos clínicos e cirúrgicos da doença. Métodos: Realizamos estudo transversal, prospectivo entre fevereiro de 2013 a fevereiro de 2015 que avaliou a porcentagem de células iNKT e os subtipos iNKT CD4+, iNKT CD4+ CCR7+, iNKT CD4+ CD25+, iNKT DN, iNKT DN CCR7+, iNKT DN CD25+, iNKT CD4+ IL6+, iNKT CD4+ IL10+, iNKT CD4+ IL17+, iNKT CD8+ IL6+, iNKT CD8+ IL10+, iNKT CD8+ IL17+, iNKT DN IL6+, iNKT DN IL10+, iNKT DN IL17+ no sangue periférico, por citometria de fluxo, em pacientes com endometriose profunda (n = 47) e sem endometriose (n = 26). As frequências de células iNKT e seus subtipos foram comparadas entre os grupos de acordo com os sintomas, fase do ciclo, estádio da doença e classificação histológica. Resultados: Na avaliação da frequência das células iNKT, iNKT DN e iNKT DN IL17+ foi evidenciada diminuição significativa nas pacientes com endometriose (p=0,010, p=0,020, p=0,050; respectivamente). Além disso, foi observada diminuição significativa nas frequências das células iNKT CD4+ CCR7+ e aumento significativo das células iNKT CD4+ IL-17+ em pacientes com endometriose e dismenorréia severa em comparação a dismenorréia ausente/leve. Nas pacientes com endometriose e dor acíclica severa observou-se diminuição significativa da frequência das células iNKT CD4+ IL17+ em comparação a dor acíclica ausente/leve (p=0,048). Houve diminuição das células iNKT nas pacientes com endometriose em relação ao grupo controle na fase secretora do ciclo menstrual (p=0,030). Na avaliação da fase do ciclo menstrual foi observado na fase proliferativa aumento significativo na frequência das células iNKT CD4+ CD25+ (p=0,022) e diminuição significativa das células iNKT DN (p=0,011) nas pacientes com endometriose. Na fase secretora foi evidenciado diminuição significativa na frequência das células iNKT DN IL17+ (p=0,049) nas pacientes com endometriose. Foi identificado também nas pacientes com endometriose uma diminuição na frequência das células iNKT DN CD25+ na fase secretora em relação a fase proliferativa do ciclo menstrual. Conclusões: As células iNKT e os subtipos iNKT DN e iNKT DN IL17+ se mostraram alteradas nas pacientes com endometriose profunda. Subtipos específicos de células iNKT estão alteradas nas pacientes com endometriose profunda em pacientes com dismenorréia e dor acíclica severas. As fases do ciclo menstrual estão relacionadas a alteração nas frequências das células iNKT e dos subtipos iNKT CD4+ CD25+, iNKT DN, iNKT DN IL17+ e iNKT DN CD25+ nas pacientes com endometriose profunda. Estes resultados sugerem participação das células iNKT no desenvolvimento da endometriose / Introduction: Endometriosis is a disease with inflammatory characteristics that affects women of reproductive age. The pathogenesis of endometriosis is unclear. There has been an association between immune disorders and endometriosis, such as changes in macrophages, NK cells, cytokines, and Th1, Th2 and Th17 responses. iNKT cells, a special type of T lymphocytes, play an important role in the inflammatory response as mediators of the Th1, Th2 and Th17 responses. Objectives: The main objective of this study was to compare the frequencies of iNKT cells and their subtypes between patients with endometriosis and patients without endometriosis. We also compare the frequencies of these cells in both groups relating to some clinical and surgical aspects of the disease. Methods: We performed a prospective cross-sectional study between February 2013 and February 2015, which evaluated the percentage of iNKT cells and iNKT CD4+, iNKT CD4+ CCR7+, iNKT CD4+ CD25+, iNKT DN, iNKT DN CCR7+, iNKT DN CD25+, iNKT CD4+ IL6+ , iNKT CD8+ IL17+, iNKT DN IL6+, iNKT DN IL10+, iNKT DN IL17+ in the peripheral blood, by flow cytometry, in patients with deep endometriosis (n = 47), iNKT CD4+ IL10+, iNKT CD4+ IL17+, iNKT CD8+ ) and without endometriosis (n = 26). The frequencies of iNKT cells and their subtypes were compared between groups according to symptoms, stage of the cycle, stage of the disease and histological classification. Results: iNKT, iNKT DN and iNKT DN IL17+ cells showed significant decrease in patients with endometriosis (p = 0.010, p = 0.020, p = 0.050, respectively). In addition, a significant decrease in iNKT CD4+ CCR7+ cell numbers and a significant increase of iNKT CD4+ IL17+ cells were observed in patients with endometriosis and severe dysmenorrhea compared to absent / mild dysmenorrhea. In patients with endometriosis and severe acyclic pain, there was a significant decrease in the frequency of iNKT CD4+ IL17+ cells compared to absent / mild acyclic pain (p = 0.048). There was a decrease in iNKT cells in patients with endometriosis compared to the control group in the secretory phase of the menstrual cycle (p = 0.030). In the menstrual cycle, a significant increase in iNKT CD4+ CD25+ cells (p = 0.022) and a significant decrease in iNKT DN cells (p = 0.011) was observed in the proliferative phase in patients with endometriosis. In the secretory phase there was a significant decrease in the frequency of iNKT DN IL17 + cells (p = 0.049) in patients with endometriosis. It was also identified in patients with endometriosis a decrease in the frequency of iNKT DN CD25+ cells in the secretory phase in relation to the proliferative phase of the menstrual cycle. Conclusions: iNKT cells and subtypes iNKT DN e iNKT DN IL17+ have been altered in patients with deep endometriosis. Specific subtypes of iNKT cells are altered in patients with deep endometriosis in patients with severe dysmenorrhea and acyclic pain. The phases of the menstrual cycle are related to changes in the frequencies of iNKT cells and subtypes iNKT CD4+ CD25+, iNKT DN, iNKT DN IL17+ and iNKT DN CD25+ in patients with deep endometriosis. These results suggest the participation of iNKT cells in the development of endometriosis
218

Analyse des bases moléculaires de la résistance tumorale à la cytotoxicité spécifique et naturelle dans le contexte microenvironnemental / Molecular basis of tumor resistance to specific and natural cytotoxicity in the microenvironmental context

Carré, Thibault 17 October 2012 (has links)
Au cours de la réponse immunitaire antitumorale, l’instabilité génétique des tumeurs combinée à la pression de sélection du système immunitaire peut conduire, via l’immunoediting, à l’émergence de variants tumoraux résistants à la lyse par les effecteurs cytotoxiques. Une meilleure compréhension de ces mécanismes potentiellement impliqués dans la susceptibilité tumorale à la lyse naturelle et/ou spécifique pourrait permettre le développement de stratégies d’immunothérapie intégratives plus efficaces. Dans ce cadre nous avons étudié un modèle de résistance à la lyse spécifique impliquant un remaniement du cytosquelette d’actine (i). Nous avons pu mettre en évidence que l’inhibition conjointe de protéines interagissant avec l’actine (caldesmone, ézrine, radixine et moésine) générait une réduction de la susceptibilité des cellules tumorales à la lyse par les lymphocytes T cytotoxiques (CTLs). Parallèlement, nous avons identifié les microARNs différentiellement exprimés entre le variant résistant et la lignée parentale et étudié leur implication dans la susceptibilité tumorale à la lyse par les CTLs. Dans le but de déterminer le rôle d’une pression de sélection par les cellules tueuses naturelles (NK pour Natural Killer), de l’immunité innée, sur les cellules tumorales et l’émergence de variants résistants, nous avons aussi établi un modèle de coculture continue de cellules tumorales de mélanomes avec des cellules NK (ii). Les cellules tumorales obtenues sont résistantes à la lyse NK (mais toujours sensibles à la lyse spécifique par un clone lymphocytaire T cytotoxique) et établissent moins de contact et de synapse immunologique avec les cellules NK que la lignée parentale. L’analyse transcriptomique a révélé la baisse d'expression de B7-H6 (ligand d'un récepteur activateur des cellules NK) qui contribue partiellement au phénomène de résistance. De nombreux gènes impliqués dans les phénomènes de migration/invasion/adhérence sont également modulés et certaines propriétés cellulaires (croissance en milieu semi-solide, adhérence, migration) semblent refléter l’acquisition d’une agressivité tumorale accrue suite à la coculture. Nous avons finalement analysé l’impact sur la réponse antitumorale de la connexine-43, impliquée dans la formation des jonctions communicantes (GJ pour Gap Junction) (iii). Nous avons montré que sa présence à la synapse entre cellules tumorales et CTL n'exerce aucun impact sur la susceptibilité à la lyse. Néanmoins, les GJs sont impliquées dans l’émergence par stimulation antigénique de lymphocyte T CD8+ spécifique hautement réactif. / During antitumor immune response, cancer cells genetic instability combined with immune system selective pressure may drive to the emergence of tumor variant resistant to lysis by cytotoxic effector cells through a phenomenon called immunoediting. A better understanding of those mechanisms putatively involved in tumor susceptibility to natural and/or specific lysis would enable new integrative and more effective immunotherapeutic strategies. In this context, we studied a model of resistance to specific lysis linked to actin cytoskeleton remodeling (i). We showed that combined inhibition of actin interacting protein (caldesmone, ezrin, radixin and moesin) reduced tumor cells susceptibility to cytotoxic T lymphocytes (CTLs) lysis. Moreover, we identified microRNAs differentially expressed between parental cell line and resistant variant and are currently studying their impact on tumor susceptibility to CTLs lysis. In order to depict the role of innate immunity Natural Killer (NK) cells selective pressure, on tumor cells and on the emergence of resistant variants, we also established a maintained coculture model of melanoma cells with NK cells (ii). Selected cells obtained were resistant to NK cells-mediated lysis (but still susceptible to CTLs-mediated specific lysis) and formed less contact and immune synapse with NK cells than parental cell line. Transcriptomic analysis revealed the reduced expression of B7-H6 (ligand of an NK cells activating receptor) partially contributing to the resistance phenotype. The expression of several genes involved in migration/invasion/adhesion is also modulated and some cell characteristics (cell growth in semi-solid medium, adhesion, migration) tend to reflect the acquisition through coculture of an increased aggressiveness. Finally, we evaluated the impact of connexin-43 (Cx43), involved in the establishment of Gap Junctions (GJs), on antitumor response (iii). We showed that despite localization at the immune synapse between tumor target cell and CTL, Cx43 and GJs do not modulate susceptibility to CTL-mediated specific lysis. Nevertheless, GJs contribute to the emergence of highly reactive specific CD8+ T lymphocytes following antigen stimulation.
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Estudo do polimorfismo dos genes KIR na esclerose sistêmica

Salim, Patrícia Hartstein January 2009 (has links)
As células Natural Killer (NK) fazem parte da resposta imune inata, sendo a primeira linha de defesa do organismo contra vírus, bactérias, tumores e microorganismos. Estas células induzem a morte da célula-alvo quando não há o reconhecimento das moléculas de antígenos leucocitários humanos (HLA) de classe I, através de seus receptores, chamados Killer cell Immunoglobulin-like Receptor (KIR). Vários estudos demonstram o envolvimento dos genes KIR na patogênese das doenças auto-imunes. Acredita-se que combinações desses genes possam ser favoráveis para o desenvolvimento da esclerose sistêmica (ES). Portanto, o conhecimento destes genes relacionados às células NK poderiam ser úteis para o entendimento da patogênese da ES. O objetivo deste estudo é investigar o polimorfismo dos genes KIR em um grupo de pacientes com ES, incluindo a forma difusa e limitada da doença. A freqüência do receptor inibidor KIR2DL2 foi significantemente menor nos pacientes comparada com a do grupo controle (28,7% versus 65,2%; P<0,001; OR=0,21; IC95% 0,11–0,38). Quando analisamos a combinação do receptor inibidor 2DL2, com a presença do ativador 2DS2 (KI2DS2+/KIR2DL2-), encontramos uma maior freqüência nos pacientes (26,1% versus 1,7%; P<0,001; OR=19,94; IC95% 4,7–175,1). Por outro lado, a presença de ambos KIR2DL2 e KIR2DS2 foi mais freqüente no grupo controle (26,9% versus 57,3%; P<0,001; OR=0,27; 95%CI 0,1–0,4). Nenhuma diferença estatística no polimorfismo dos genes KIR foi encontrada entre a forma difusa e a forma limitada. A combinação KIR2DS2+/KIR2DL2– parece ser um fator de risco para o desenvolvimento da ES enquanto a alta freqüência do gene inibidor KIR2DL2 no grupo controle parece ter uma função protetora. Estes resultados indicam um potencial papel dos genes KIR na patogênese da ES. / Natural killer (NK) cells have an important role in the early responses to viral infections. They kill diverse target cells with decreased or absent expression of major histocompatibility complex (MHC) class I molecules through the Killer Cell Immunoglobulin-Like Receptors (KIR). Many studies have reported association of KIR genes with autoimmune diseases. The objective of this study is to investigate possible associations of KIR polymorphisms with systemic sclerosis (SSc), including the limited (lSSc) and diffuse (dSSc) forms of the disease. The frequency of inhibitory KIR2DL2 was significantly decreased among patients with SSc compared with healthy controls (28.7% versus 65.2; P<0.001, odds ratio [OR] 0.21, 95% confidence interval [95% CI] 0.11–0.38). When activatory and inhibitory KIR genes were analyzed in combination, the concomitant presence of KIR2DS2 and absence of KIR2DL2 (KI2DS2+/KIR2DL2-) phenotype was more frequent in SSc patients than in the control group (26.08% versus 1.75%; P<0.001, OR=19.94, 95%CI [4.78–175.10]). On the other hand, the presence of both KIR2DS2 and KIR2DL2 was more frequent in the control group (26.96% versus 57.39%; P=0.000005, OR=0.27, 95%CI [0.15–0.49]). No significant difference in KIR genes polymorphisms was found between lSSc and dSSc disease subsets. The combination of KIR2DS2+/KIR2DL2– may be a risk factor for development of SSc while the higher frequency of the inhibitory KIR2DL2 gene in the control group suggest to a protective effect. These results indicate a potential role of KIR genes in the SSc pathogenesis.
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Estudo do polimorfismo dos genes KIR e HLA em pacientes com câncer de mama e grupo controle

Jobim, Maria Regina Sampaio Leite January 2014 (has links)
O presente estudo tem como objetivo investigar a frequência dos diversos polimorfismos dos genes KIR (Killer Immunoglobulin-like Receptors) e HLA C1 e C2 em um grupo de pacientes com câncer de mama e comparar com um grupo controle de indivíduos sadios. As células natural killer (NK) são linfócitos que diferem das células T e B e que fazem parte da imunidade natural, reconhecendo as moléculas HLA (Antígenos Leucocitários Humano) de classe I em células infectadas por vírus ou em células tumorais, através de seus receptores de membrana. Os principais receptores das células NK são conhecidos como receptores KIR, sendo codificados por genes localizados no cromossomo 19q13.4 e classificados em grupos funcionais supressores e ativadores. Neste estudo, analisamos 15 genes KIR e alelos do sistema HLA de classe I em 230 pacientes caucasóides e em 278 controles, usando a técnica de PCR com primers específicos (PCR-SSO e PCR-SSP). Nossos resultados demonstraram uma frequência maior do genótipo supressor 2DL2 (P<0,001) em pacientes com câncer de mama, quando comparados ao grupo controle. Os genes HLA-C2 e HLA-BW4 não apresentaram diferenças significantes entre os grupos. Contudo, o gene HLA-C1 foi observado em maior frequência nos pacientes com câncer de mama. Considerando que estes achados sugerem uma potencial associação entre o sistema de genes KIR, HLA classe I e o câncer de mama, estudos adicionais sobre este tema são necessários. / We investigated the frequency of various KIR (Killer Immunoglobulin-like Receptors) and HLA C1 and C2 gene polymorphisms in a group of patients with breast cancer and healthy controls. Natural Killer (NK) cells are lymphocytes that differ from T and B cells and are part of the innate immune system, recognizing class I Human Leukocyte Antigens (HLA) molecules on target cells (virus-infected as well as cancer cells), through specific cell surface receptors. KIR comprises the main class of NK receptors, being encoded by genes located in chromosome 19q13.4. They possess both suppressor and activating functional groups. Fifteen KIR genes and class I HLA alleles obtained from 230 Caucasians patients, as well as 278 controls were studied, using PCR techniques with specific primers (PCR-SSO and PCR-SSP). Our results showed a higher frequency of suppressor genotype 2DL2 (P<0,001) in patients with breast cancer as compared to controls. No significant difference between HLA-C2 and HLA-BW4 alleles were observed between the study groups. Notably, a higher frequency of HLA-C1 gene was noted in patients with breast cancer. Our results suggest a potential association between KIR genes, HLA class I and breast cancer, deserving further investigation.

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