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Efeitos in vivo e ex vivo de compostos derivados do nitroestireno na resposta imunohematopoética / In vivo and ex vivo effects of Nitrostyrene compounds in the munohematopoietic responseCalgarotto, Andrana Karla, 1983- 20 August 2018 (has links)
Orientador: Mary Luci de Souza Queiroz / Tese (doutorado) - Universidade Estadual de Campinas, Faculdade de Ciências Médicas / Made available in DSpace on 2018-08-20T00:13:54Z (GMT). No. of bitstreams: 1
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Previous issue date: 2012 / Resumo: Neste trabalho avaliamos os efeitos de compostos derivados do nitroestireno, NTS1 e NTS2, sobre a resposta imunohematopoética de camundongos normais e portadores do tumor ascítico de Ehrlich (TAE). O estudo dos mecanismos envolvidos no tratamento de camundongos com NTS1 e NTS2 frente às alterações induzidas pelo TAE mostra efeitos imunológicos distintos dos dois compostos. O composto NTS1 induziu aumentos significativos na atividade de células NK, na proliferação de células mononucleares esplênicas e na produção de citocinas com padrão Th1 (IL-2 e IFN-?) liberadas por células mononucleares do baço. Em contrapartida, a atividade de NTS2 esteve relacionada com ativação macrofágica. Nossos resultados demonstram que o tratamento com NTS2 promove aumento significativo nos níveis de TNF-a e IL-1 no sobrenadante da cultura de macrófagos peritoneais. Outro efeito importante de NTS2 sobre macrófagos peritoneais foi o estímulo na produção de NO2-. Além dos parâmetros imunológicos citados, avaliamos, os efeitos de NTS1 e NTS2 sobre o crescimento e diferenciação de precursores hematopoéticos. Tanto NTS1 como NTS2 foram capazes de reverter a mielossupressão provocada pela evolução do tumor, além de aumentar a atividade estimuladora de colônias (CSA) no soro de camundongos Balb/c. Os resultados obtidos demonstram que os compostos compartilham da habilidade de regular positivamente os desequilíbrios hematopoéticos e imunológicos envolvidos na evolução temporal do TAE. A partir disso, testamos a capacidade dos compostos no processo de diferenciação mielocítica utilizando um sistema de cultura ex- vivo no qual células humanas CD34+ foram tratadas com NTS1 e NTS2. Nossos resultados apresentaram atividade dose-dependente de NTS1 e NTS2 na proliferação e viabilidade de células CD34+. Além de aumentar significativamente o número de progenitores mielóide comum e para granulócitos de macrófagos. Os compostos apresentaram diferentes efeitos durante o processo de diferenciação. Inibiram a formação de neutrófilos maduros, porém, NTS1 aumentou significativamente a produção de metamielócitos e NTS2 de monócitos. Estes efeitos fenotípicos na proliferação e na diferenciação observados após o tratamento com NTS1 e NTS2 podem estar relacionados com a via p38MAPK e o fator transcricional CEBP-a / Abstract: In this work, we have investigated the effects of two nitrostirene derivatives compounds, NTS1 and NTS2, in the immune-hematopoeitic system in normal and Ehrlich ascites tumor (EAT)-bearing mice. The study of the mechanisms involved in the treatment produced by the NTS1 and NTS2 against induced alterations by EAT were different, showing significant improvements in the NK cells activity, proliferation and Th1 (IL-2 and INF-?) by mononuclear spleen cells. On the other hand, NTS2 activity was related to macrophage activation. Our results show that treatment with NTS2 promotes significant increase in the TNF-a and IL-1 levels in supernatants of the cultures of peritoneal macrophages. Another important effect of NTS2 on peritoneal macrophage was the stimulation in the production of NO2-. Beyond immunological parameters, we investigated the NTS1 and NTS2 effects on hematopoietic progenitors. Treatment with NTS1 and NTS2 protected the host of myelosuppression caused by tumor development and increase the colony-stimulating activity (CSA) in the serum of Balb/c mice. The results showed that NTS1 and NTS2 share the ability of regulating positively the hematopoietic and immunological unbalance involved in the TAE development. Concerning their effects on myelopoiesis, we investigated the compounds utilizing an ex-vivo differentiation system in which umbilical cord blood derived CD34+ cells were treated with NTS1 and NTS2. Our results show that NTS1 and NTS2 have concentration dependent effects on proliferation and viability of CD34+ cells. Moreover, NTS1 and NTS2 significantly increase common myeloid and granulocyte/macrophage progenitors. The compounds have differential effects on terminal differentiation, inhibiting mature neutrophil, however, NTS1 significantly increased metamyelocytes and NTS2 monocytes. The phenotypic effects on proliferation and differentiation observed after NTS1 and NTS2 treatment can be explained by changes in p38MAPK cell signaling and with CEBP-a transcription factor / Doutorado / Farmacologia / Doutor em Farmacologia
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Caracterização das células natural killer (NK) circulantes no sangue periférico precocemente após o transplante de células-tronco hematopoéticas (TCTH)Gonçalves, Alice Dahmer January 2017 (has links)
O transplante de células-tronco hematopoéticas alogênico (alo-TCTH) é uma opção de tratamento para uma variedade de doenças neoplásicas e não neoplásicas, principalmente de origem hematológica sendo doença do enxerto-contra-hospedeiro (DECH) a sua principal complicação. As células Natural Killer (NK) são os primeiros linfócitos a se recuperarem após o TCTH. Além da capacidade de promover o efeito enxerto-versus-leucemia (EVL), as células NK do doador parecem capazes de promover a pega do enxerto e de prevenir o desenvolvimento da DECH. As células NK compreendem aproximadamente 10% dos linfócitos do sangue periférico e são caracterizadas fenotipicamente pela expressão do antígeno de superfície CD56 (CD, cluster of differentiation) e pela ausência de CD3 (CD56+CD3-). O subtipo de células NK CD56dim (baixa densidade do antígeno) é naturalmente mais citotóxico que o subtipo CD56bright (alta densidade do antígeno) o qual é caracterizado pela capacidade de produção de citocinas. Com base nisso, o objetivo do trabalho é avaliar a presença de células NK nos dias 7, 14, 21 e 28 após o TCTH alogênico e autólogo, caracterizando sua frequência, seu imunofenótipo e a sua capacidade de produzir fatores de crescimento hematopoético e citocinas relacionadas. / Allogeneic hematopoietic stem cell transplantation (allo-HSCT) is an option of treatment for a variety of neoplastic and non-neoplastic diseases and graft-versus-host disease (GVHD) is its main complication. Natural Killer cells (NK) are the first lymphocytes to recover after HSCT. In addition to the ability to promote graft versus leukemia effect (GVL), donor NK cells appear to be capable of promoting engraftment and preventing the development of GVHD. NK cells comprise approximately 10% of peripheral blood lymphocytes and are characterized phenotypically by the expression of the CD56 surface antigen and absence of CD3 (CD56 + CD3-). The CD56dim (low density of antigen) NK cell subtype is naturally more cytotoxic than the CD56bright (high density of antigen) subtype which is characterized by the ability to produce cytokines. Based on this, the objective of the study is to evaluate the presence of NK cells on days 7, 14, 21 and 28 after allogeneic and autologous HSCT, characterizing their frequency, their immunophenotype and their capacity to produce hematopoietic growth factors and related cytokines.
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A Small Molecule Drug Screening Identifies the Antibiotic Colistin Sulfate as an Enhancer of NK Cell CytotoxicityCortés-Kaplan, Serena 16 August 2021 (has links)
Cancer immunotherapy is an encompassing term referring to therapeutic strategies that aim to boost the immune system to fight cancer. These strategies include administering immune cells that have been altered to have greater anti-tumor activity or using biologics and small molecules that target immune components to also promote tumor clearance. Natural Killer (NK) cells are cells of the innate immune system that recognize and kill abnormal cells such as cancer cells and play an important role in the anti-tumor response. Because of their crucial role in tumor immunity, NK cells are prime targets for immunotherapies. Repurposing small molecule drugs is an attractive strategy to identify new immunotherapies from already approved drugs. Here, we screened 1,200 approved drugs from the Prestwick Chemical Library to identify drugs that increase NK cell cytotoxicity. We used a high-throughput luciferase-release cytotoxicity assay to measure the killing of the myeloid leukemia cell line, K562 cells expressing nano luciferase (NL) by NK92 cells, a human NK cell line. From the drug candidates identified from the screening assay, the antibiotic colistin sulfate increased cytotoxicity of the NK92 cell line and unstimulated human NK cells towards K562-NL cells. This increase in NK cytotoxicity was short-lived as pre-treating NK92 cells with colistin for 1 hour or 24 hours did not increase cytotoxicity. Also, we show pre-treating K562-NL target cells with colistin does not sensitize them to NK-mediated killing. Further studies are needed to uncover the mechanism of action of colistin, thus contributing to knowledge of fundamental NK cell biology regarding NK cell cytotoxicity which will aid in identifying additional small molecule drugs that enhance NK cell activity.
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Understanding Immune Suppression in Patients with Chronic Hepatitis C Virus InfectionsOkwor, Chisom Ifeoma Adaeze 02 March 2021 (has links)
Hepatitis C Virus (HCV) is a small RNA virus that progresses to chronicity in 50-80% of infected individuals. Direct-acting antivirals (DAAs) are revolutionary treatments for HCV with 90-98% cure rates. However, over time, chronic HCV infections can result in advanced liver disease, including cirrhosis. Patients with advanced fibrosis experience a poor response to vaccination, recurrent infections and increased risk for hepatocellular carcinoma (HCC). These outcomes are, in part, a consequence of immune dysfunction. Increased inhibitory receptor and Galectin-9 (GAL-9) expression is a possible mechanism promoting lymphocyte dysfunction.
In this study, blood samples were collected from chronic HCV patients with different degrees of liver fibrosis. I conducted a 13-parameter flow stain on the peripheral blood mononuclear cells (PBMC) of these patients. Next, I measured the expression of inhibitory receptors (PD-1, CTLA-4, LAG-3, TIGIT and TIM-3) and GAL-9 on bulk T cell and NK cells of 15 chronic HCV patients with no to moderate fibrosis (F0-F2) and 15 with advanced fibrosis (F3-F4). To analyze receptor co-expression, I employed t-distributed stochastic neighbor embedding (t-SNE) analysis to dimensionally reduce the multi-parametric data.
Notably, I found that F3-F4 patients had higher frequencies of >3 inhibitory receptor co-expression on NK cells. Moreover, t-SNE analysis of bulk T cells revealed that F3-F4 patients manifest a higher frequency of cells in the clusters with CD25+TIGITmed-hi CD4+ T cells and PD-1medLAG-3med-hiGAL-9med-hi CD4+ T cells. t-SNE analysis of NK cells also showed that F3-F4 patients manifest a higher frequency of cells in the cluster with CD25+TIGITmed-hiTIM-3med-hi CD56Dim NK cells and CCR7+ PD-1medLAG-3med-hiGAL-9med-hi CD56Dim NK cells. Lastly, the frequency of cells in these clusters was found to positively correlate with patient’s extent of liver damage. In conclusion, I identified phenotypes of immune dysregulation that could explain the increased susceptibility to infection and HCC in chronic HCV patients with advanced fibrosis. These phenotypes could identify targets for combinatorial checkpoint blockade therapy to potentially improve immune function in these patients.
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Exploring molecular patterns and determinants of melanoma cell susceptibility to natural killer cell cytotoxicityCappello, Sabrina 14 June 2021 (has links)
No description available.
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Elucidation of the Mechanism by which Phosphatase and Tensin Homologue Deleted on Chromosome Ten (PTEN) Regulates Natural Killer Cell FunctionBriercheck, Edward Lloyd 03 September 2013 (has links)
No description available.
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Humanized mouse models with endogenously developed human natural killer cells for in vivo immunogenicity testing of HLA class I-edited iPSC-derived cells / HLAクラスI編集iPS細胞由来細胞のインビボ免疫原性検証を可能とする内在発生ヒトNK細胞を有するヒト化マウスモデルFlahou, Charlotte Astrid Denise 25 September 2023 (has links)
京都大学 / 新制・課程博士 / 博士(医科学) / 甲第24885号 / 医科博第152号 / 新制||医科||10(附属図書館) / 京都大学大学院医学研究科医科学専攻 / (主査)教授 河本 宏, 教授 濵﨑 洋子, 教授 上野 英樹 / 学位規則第4条第1項該当 / Doctor of Medical Science / Kyoto University / DFAM
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Evalutation of Human Platelet Lysate in NK Cell CultureWilliamson, Elizabeth 01 January 2020 (has links)
Natural Killer (NK) cells can recognize and lyse a large variety of tumor cells and have been of interest as a potential cancer treatment option. Our group has developed a particle-based NK cell expansion method that utilizes plasma membrane particles (PM-particles) derived from K562 cells genetically engineered to express membrane bound IL21 and 41BBL(K562-mbIL21-41BBL), two proteins that stimulate growth and activity of NK cells. This method selectively expands highly cytotoxic NK cells > 400-fold in 14 days of culture. Currently NK cells are expanded in vitro using Fetal Bovine Serum (FBS) as a serum-supplement to promote cell growth. While effective, the use of animal products is not preferred in cell cultures grown for clinical purposes. This project tested Human Platelet Lysates (HPL) as a potential replacement for FBS in NK cell culture. NK cells were expanded using PM21-particle based expansion method with either FBS or HPL as supplements. Their growth characteristics, phenotype and functionality were assessed and compared. Results of this study determined that HPL is a viable option to replace FBS in NK cell culture for clinical applications, as there was no significant difference between the two serum supplements.
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Mechanism of IL-12 Mediated Enhancement of Passive Experimental Autoimmune Myasthenia GravisBrown, Paul Michael January 2010 (has links)
No description available.
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Étude génétique et fonctionnelle des Interferon-producing Killer Dendritic CellsGuimont-Desrochers, Fanny 12 1900 (has links)
L’idée qu’une cellule puisse effectuer la cytolyse de cellules transformées, comme une cellule Natural Killer (NK), tout en ayant la capacité de présenter des antigènes, comme une cellule dendritique (DC), peut sembler fantaisiste. Cependant, de telles cellules furent bel et bien identifiées chez la souris en 2006. Ces cellules, nommées Interferon-producing Killer Dendritic Cells (IKDC), furent l’objet d’une caractérisation extensive qui révéla leur énorme potentiel immunologique. La combinaison de fonctions associées à des cellules NK et à des DC a doté les IKDC d’un pouvoir antitumoral remarquable. D’ailleurs, il a été démontré que les IKDC sont plus efficaces que les cellules NK pour limiter la croissance tumorale. Ainsi, suite à leur découverte, les IKDC ont suscité beaucoup d’intérêt.
Cependant, une controverse émergea sur la nature des IKDC. Plusieurs groupes indépendants tentèrent de reproduire les expériences attestant les fonctions de DC des IKDC, sans y parvenir. De plus, des études additionnelles révélèrent que les IKDC possèdent des similitudes très importantes avec les cellules NK. Ces observations ont mené la communauté scientifique à suggérer que les IKDC sont des cellules NK en état d’activation (aNK).
Malgré cette controverse, les caractéristiques antitumorales des IKDC sont si uniques et considérables qu’il est primordial de poursuivre l’étude de ces cellules. Pour y arriver, il est essentiel de déterminer la nature des IKDC et de mettre fin à ce débat. Par la suite, il sera important d’identifier des façons de cibler spécifiquement les IKDC pour permettre leur usage dans le cadre de thérapies antitumorales. Ainsi, l’objectif de cette thèse est de définir l’identité des IKDC, puis de déterminer les facteurs génétiques responsables de la régulation de ces cellules.
Nous avons démontré que les IKDC ne sont pas des cellules aNK, contrairement à ce qui avait été suggéré. Nous avons constaté que les IKDC prolifèrent activement et possèdent un phénotype unique, des caractéristiques associées à des cellules NK très immatures. Afin de déterminer si les IKDC peuvent acquérir un phénotype mature, nous avons effectué des expériences de transfert adoptif. Suite à leur injection in vivo, les IKDC acquièrent un phénotype de cellules matures, mais étonnamment, elles se différencient aussi en cellules NK. Ainsi, nous avons révélé que les IKDC sont un intermédiaire dans la différenciation des cellules NK. En parallèle, nous avons démontré que la proportion d’IKDC varie grandement entre des souris de fond génétique différent, indiquant que des facteurs génétiques sont impliqués dans la régulation de ces cellules. Nous avons alors effectué une analyse génétique qui a révélé que les IKDC sont régulées par des facteurs génétiques compris dans une région distale du chromosome 7. Les résultats présentés dans cette thèse constituent une avancée importante pour la recherche sur les IKDC. Ils ont permis de définir la nature des IKDC et d’identifier un intervalle génétique impliqué dans la régulation de ces cellules. Ces découvertes sont des connaissances précieuses pour l’identification des IKDC chez l’Homme et la création de nouvelles thérapies dans la lutte contre le cancer. / The idea that a cell could kill transformed cells, like a Natural Killer (NK) cell, all the while exhibiting also the capacity to present antigens to T cells, like a Dendritic Cell (DC), may seem farfetched. However, in mice, a cell presenting these specific properties was identified in 2006. These cells were named Interferon-producing Killer Dendritic Cells (IKDC) and extensive studies revealed that they were endowed with an important immunological potential. Indeed, the fact that IKDCs exhibit properties of both DC and NK cells conferred them with an exceptional anti-tumor potential. Notably, on a per cell basis, the in vivo anti-tumor activity of IKDCs is more efficient than NK cells. Therefore, following their identification, IKDCs showed great therapeutic promise.
However, a debate on the cell lineage origin of IKDCs emerged. Several independent groups could not replicate the finding that IKDCs showed functional antigen-presentation properties similar to DCs. Also, additional studies revealed that IKDCs are very similar to NK cells. These and other observations led the scientific community to believe that IKDCs were activated NK cells.
Despite this controversy, IKDCs clearly exhibit a unique and outstanding anti-tumor potential, highlighting the relevance to further explore these cells. We must first close the debate regarding the lineage origin of IKDCs. We subsequently need to identify a means to specifically target IKDCs to facilitate their use in novel anti-tumor therapies. Thus, the objective of my thesis is first, to define the identity of IKDCs and second, to determine the genetic factors implicated in the regulation of these cells.
For the first objective, we demonstrated that IKDCs do not represent activated NK cells, as previously suggested. We show that IKDCs are highly proliferative and exhibit a unique phenotype associated with very immature NK cells. In an attempt to verify if IKDCs could acquire a mature phenotype, we conducted an adoptive transfer experiment. We found that, after adoptive transfer, IKDCs adopt a mature phenotype, but also surprisingly differentiate into NK cells. These findings indicate that IKDCs represent an intermediate in NK-cell differentiation. For the second objective, we demonstrated that the IKDC proportion was highly variable between strains of different background origins, indicating that these cells are regulated by genetic factors. A genetic study revealed that genetic factors in distal arm of chromosome 7 associate with the proportion of IKDCs. The results presented in this thesis represent an important breakthrough for the research on IKDCs. They allowed to define the cell lineage origin of IKDCs and to identify a genetic region involved in the regulation of this cell type. These discoveries are valuable knowledge for the identification of human IKDCs and the development of novel anti-tumor therapies.
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