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Implication physiopathologique de l'adaptateur LNK : mécanismes d'action et perspectives thérapeutiques dans les Néoplasmes Myéloprolifératifs / Physiopathological implication of LNK adaptor : mechanisms of action and therapeutic applications in myeloproliferative neoplasmsJungalee, Anouchka 15 December 2016 (has links)
L’adaptateur LNK est un régulateur négatif des voies de signalisation, dont la voie JAK/STAT,essentielle au développement du système hématopoïétique. Son implication dans les hémopathies chroniques, notamment les Néoplasmes Myéloprolifératifs (NMP), a été mise en évidence par l’analyse de souris invalidées pour cet adaptateur et l’identification de mutations de LNK chez les patients atteints de ces pathologies. Toutefois, le mécanisme permettant la régulation de ses partenaires, dont la kinase JAK2, et l’implication fonctionnelle des mutations de LNK dans les NMP, restent à définir. Ainsi, mon projet de thèse a porté sur l’analyse structurale et fonctionnelle des complexes de signalisation LNK/JAK2 et sur le développement d’une stratégie moléculaire pour l’utilisation thérapeutique de LNK dans les NMP. Nos résultats ont montré pour la première fois, la fonction inhibitrice de la région N-terminale incluant le domaine d’homologie à la Pleckstrine deLNK sur JAK2 normale et de manière plus importante, sur la forme mutée JAK2-V617F, retrouvée chez les patients atteints de NMP. De plus, nos études sur les mutations de LNK localisées dans cette région régulatrice, ont permis de comprendre leur contribution dans le développement de ces hémopathies et de proposer un mécanisme d’inhibition de l’activation de JAK2 par LNK. Nos résultats permettent d’utiliser le ciblage de la région N-terminale de LNK comme stratégie moléculaire inhibant spécifiquement la forme oncogénique JAK2-V617F à l’aide de peptides pénétrants (CPP). A long terme, cette approche pourrait être utilisée comme outil thérapeutique dans le traitement de patients atteints de NMP positifs pour JAK2-V617F. / The LNK adaptor protein is a key negative regulator of signalling pathways, such as JAK/STAT, important in the development of the hematopoietic system. Its implication in chronic blood diseases, such as Myeloproliferative Neoplasms (MPN) has been confirmed by studies on Lnk-deficient mice, as well as the identification of LNK mutations in MPN patients. However, the LNK mechanism of regulation on its partners and the functional implication of LNK mutations in MPN pathogenesis, are still unclear. Therefore, my PhD project covers the structural and functional analysis of theLNK/JAK2 signalling complex and the development of a molecular strategy to use LNK as a therapeutic tool for the treatment of MPN patients. Our study showed, for the first time, the inhibitory function of the N-terminal region and the pleckstrin homology domain of LNK on JAK2 activity, which occurs more importantly on JAK-V617F than JAK2 wild type form. Moreover, our study provided evidence on how LNK mutations located in this LNK region could contribute to these haematological diseases and has allowed us to propose a model for LNK regulatory function on JAK2activity. Furthermore, we developed a cell penetrating peptide-based strategy to deliver this regulatory region of LNK in hematopoietic cells to specifically inhibit JAK2-V617F oncogenic form. The finalaim is to use this region as a therapeutic molecule to treat JAK2-V617F-positive MPN patients.
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A memória das máquinas = um estudo de história da técnica em São Paulo / The machine's memory : a study of history of history techniques in São PauloAndrade, Francisco de Carvalho Dias de, 1984- 17 August 2018 (has links)
Orientador: Marcos Tognon / Dissertação (mestrado) - Universidade Estadual de Campinas, Instituto de Filosofia e Ciências Humanas / Made available in DSpace on 2018-08-17T12:08:22Z (GMT). No. of bitstreams: 1
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Previous issue date: 2011 / Resumo: A proposta deste estudo é revisitar alguns temas da história da técnica em São Paulo, procurando, por meio do recurso às mais diversas fontes históricas e pelo diálogo com diferentes áreas do conhecimento, ressaltar a riqueza das contribuições que o estudo desse tema pode trazer para o entendimento de nosso passado histórico. Ao mesmo tempo, procurou-se direcionar a presente dissertação para uma análise dos fenômenos técnicos aqui abordados enquanto elementos constituintes do patrimônio cultural brasileiro. Assim, tanto por meio de uma análise das características que assumiram entre nós - e dos contextos que pautaram seu desenvolvimento - como pela problematização de alguns conceitos comumente associados a essas manifestações da técnica, intentou-se contribuir com sua valorização enquanto bens culturais dignos de preservação / Abstract: This study tries to discuss some aspects of the history of technique in São Paulo. To attempt this purpose it will use a great variety of historical sources in dialogue with some areas of knowledge. The main goal of this work is to prove that this kind of research can improve the understanding of our own historical past. The analysis of the technical phenomena studied in these pages has the intention to see them as important elements of the Brazilian cultural heritage too. Through the description of their characteristics in our country, and of their development in a specific context, this work wants, finally, to criticize some vulgar opinions about these technical facts / Mestrado / Politica, Memoria e Cidade / Mestre em História
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Análises de mutações no gene JAK2 em pacientes com diagnóstico clínico de Policitemia Vera atendidos em um único centro da cidade de Juiz de ForaFreitas, Renata Mendes de 21 February 2014 (has links)
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Previous issue date: 2014-02-21 / CAPES - Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / As Neoplasias Mieloproliferativas são originadas por uma proliferação clonal de um
progenitor hematopoético. Descrita inicialmente em 1951 como “Doenças
Mieloproliferativas” e reavaliada pela Organização Mundial da Saúde em 2011, as
Neoplasias Mieloproliferativas agrupam a Policitemia Vera, Trombocitemia Essencial
e Miefibrose Primária em um subgrupo chamado de BCR-ABL negativo. De acordo
com a revisão dos critérios adotados para o diagnóstico das Neoplasias
Mieloproliferativas a presença da mutação JAK2 V617F é considerada critério de
maior importância para o diagnóstico do subgrupo BCR-ABL negativo representando
um marcador clonal. A Policitemia Vera é principalmente diagnosticada por um
aumento na massa eritrocitária independente de fator estimulante, aumento de
leucócitos no sangue periférico, esplenomegalia e trombocitose. Ocorre, geralmente,
em homens e mulheres com faixa etária de 60 anos, com incidência de 0,7 a
2,6/100.000 habitantes/ano. A mutação V617F no gene JAK2 produz uma proteína
alterada que ativa constitutivamente a via JAK-STAT e outras vias downstream de
modo que, as proteínas de ativação transcricional e transdutoras de sinal (STAT do
inglês Signal Transducerand Activator of Transcription) são fosforiladas
posteriormente impactando na expressão de genes envolvidos na regulação da
apoptose e proteínas regulatórias, além de alterar a taxa de proliferação das células
hematopoéticas. Neste trabalho foram selecionados 26 pacientes com Policitemia
Vera, os quais foram atendidos na cidade de Juiz de Fora, Minas Gerais. Foram
realizadas análises de mutações no gene JAK2 a partir do material genético isolado
do sangue periférico. Os dados clínicos de cada paciente foram relacionados entre si
e correlacionados com os dados moleculares. / Myeloproliferative neoplasms (MPN) are caused by a clonal proliferation of a
hematopoietic progenitor. First described in 1951 as “Myeloproliferative Diseases”
and reevaluated by the World Health Organization in 2011 (WHO, 2011), the
Myeloproliferative Neoplasms gather the Polycythemia Vera, Essential
Thrombocythemia and Primary Mielofibrose in a subgroup called negative BCR-ABL.
According to WHO the revised diagnosis criteria for myeloproliferative neoplasms,
the presence of JAK2 V617F mutation, is considered the most important criterion for
the diagnosis of negative BCR-ABL subgroup representing a clonal marker. The
Polycythemia Vera is primarily diagnosed by an independent stimulating factor in red
cells mass increasing, followed by an increase of leukocytes in peripheral blood,
spleen and thrombocytosis. It usually occurs in men and women of all age groups
with higher incidence in 60-year-old patients ranging from 0.7 to 2.6/ 100.000
hab/year. The V617F mutation in the JAK2 gene produces an altered protein that
activates constitutively the JAK-STAT pathway and other pathways downstream as a
result the protein transcriptional activation and signal transduction (STAT) are
subsequently phosphorylated causing impact in the expression of genes involved in
regulation of apoptosis and regulatory proteins, as well as altering the rate of
proliferation of hematopoietic cells. In this study 26 patients with Polycythemia Vera
were selected in Juiz de Fora, Minas Gerais. The peripheral blood was used for
genetic material isolation (JAK2 mutation). The clinical data of each patient were
related to each other and correlated with the molecular data.
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Impact de l'IL-13 dans l'acquisition des fonctions tumoricides des macrophages : rôle des récepteurs lectine de type-C et implication dans la progression d'un lymphome T / Role of IL-13 in the acquisition of antitumor activities of macrophages : involvement of C type lectin receptors and implication in T-cell lymphoma developmentAla Eddine, Mohamad 23 June 2016 (has links)
Les macrophages associés aux tumeurs (TAMs) proviennent des monocytes circulants attirés par l'inflammation chronique due à la tumeur. Ces monocytes vont se différencier en une variété de macrophages en fonction des médiateurs présents dans le microenvironnement tumoral. Ainsi, il est admis que les macrophages peuvent stimuler la croissance tumorale (macrophages classiquement appelés M2), mais peuvent aussi reconnaitre et éliminer spécifiquement les cellules transformées (macrophages M1). Cette dichotomie fonctionnelle est dépendante du stade de développement cancéreux et plus spécifiquement de l'évolution du microenvironnement tumoral. De manière générale, l'infiltration et la densité élevée des TAMs au niveau de la tumeur sont corrélées à un mauvais pronostic et de ce fait les TAMs sont considérés comme une cible thérapeutique importante. Dans ce travail de thèse, nous nous sommes attachés dans un premier temps à caractériser le phénotype et les fonctions des macrophages au cours de l'évolution de la tumeur. La mise en place d'un modèle murin préclinique de lymphome T (cellules EL4) nous a permis de montrer que les macrophages présents à un stade tardif du développement tumoral, sont capables de stimuler la prolifération des cellules tumorales. Ces macrophages produisent des facteurs pro-angiogéniques, comme le TGF-ß, et immunosuppresseurs, comme l'IL-6, l'IL-10 et l'Indoléamine dioxygénase (IDO). De manière intéressante, nous avons démontré la capacité de l'IL-6, sécrétée en grande quantité dans l'ascite tumorale, à induire la différenciation des macrophages résidents en macrophages M2 pro-tumoraux. Inversement, nous avons montré que des macrophages murins résidents activés par l'IFN-? ou l'IL-13, cytokines non présentes dans l'ascite tumorale, acquièrent un phénotype anti-tumoral. Alors que l'IFN-? est connu pour induire un macrophage M1 présentant un puissant potentiel tumoricide, nous montrons que l'IL-13, qui polarise les macrophages vers un phénotype alternatif (M2), peut aussi différencier les macrophages vers un phénotype anti-tumoral. Dans ce contexte, nous avons étudié les mécanismes anti-tumoraux des macrophages polarisés par l'IL-13 vis-à-vis des cellules lymphoblastoïdes T. De façon originale, nous avons montré que les macrophages activés par l'IL-13 induisent la nécrose des cellules EL4, en produisant des radicaux libres oxygénés (RLO) et en déplétant l'arginine par l'augmentation de l'activité arginase. Nous avons également montré que les récepteurs Mannose et Dectine-1(Récepteurs Lectine de type-C), fortement exprimés par les macrophages activés par l'IL-13, reconnaissent les cellules tumorales et déclenchent la production des RLO en activant la voie Syk-P47phox. Ils induisent aussi la surexpression de l'arginase en activant la libération d'acide arachidonique et la production des HETEs (acide hydroxy-eicosatétraénoïque), agonistes naturels du récepteur nucléaire PPAR?. De plus, nous avons pu valider, in vivo, la capacité de l'IL-13 à reprogrammer les macrophages pro-tumoraux associés au lymphome T vers un phénotype anti-tumoral et à induire une régression de la tumeur. Ces résultats ont été confirmés par la diminution de la charge tumorale des souris porteuses de lymphome T, après un transfert adoptif des macrophages activés par l'IL-13. Enfin, nous avons établi que l'IL-13 active aussi les fonctions anti-tumorales des macrophages dérivés de monocytes humains contre diverses cellules tumorales humaines. Ce travail illustre la complexité du paradigme M1/M2 dans la description des fonctions pro- et anti-tumorales des macrophages. Ainsi, nos travaux démontrent la capacité de l'IL-13 à stimuler les défenses anti-tumorales des macrophages dans le cadre d'un lymphome T. Ce travail montre également que la modulation efficace des récepteurs Mannose et Dectine-1 par l'IL-13 pourrait permettre d'orienter l'interaction " cellules tumorales-macrophages " pour le bénéfice de l'hôte. / Tumor-associated macrophages (TAMs) are derived from circulating monocytes attracted by the chronic inflammation in the tumor. These monocytes differentiate into a variety of macrophages according to the mediators present in tumor microenvironment. Thus, it is known that macrophages can stimulate tumor growth (usually called M2 macrophages) but may also, in other circumstances, specifically recognize and eliminate transformed cells (M1 macrophages). This functional dichotomy is dependent on the stage of cancer development and specifically on tumor microenvironment. In general, the infiltration and the high density of TAMs in the tumor are associated with poor prognosis and consequently, TAMs might be an important therapeutic target. In this work, we first focused on the phenotype and the functions of the macrophages associated to tumor progression. The use of a preclinical mouse model of T-cell lymphoma (EL4 cells) has shown that macrophages associated to the late stage of tumor development stimulate EL4 tumor cell proliferation. These macrophages produce pro-angiogenic factors like TGF-ß and immunosuppressive mediators, such as IL-6, IL-10 and Indoleamine dioxygenase (IDO). Interestingly, we have shown that IL-6, highly secreted in tumor ascites, can improve protumoral functions of resident macrophages. Conversely, murine resident macrophages activated by IFN-? or IL-13, cytokines not detected in the tumor ascites, acquire an antitumor phenotype. While IFN-? is known to induce M1 macrophages with a powerful tumoricidal potential, we report that IL-13, which stimulate alternative phenotype (M2) of macrophages, can induce antitumor functions of macrophages. In this context, we studied the antitumor mechanisms of IL-13-activated macrophages against T-lymphoma cells. We report that IL-13-activated macrophages exert antitumor activity by promoting T-lymphoma cell necrosis through ROS release and arginase induced-L-arginine depletion. In fact, L-arginine degrading enzymes have been suggested as antitumor agents against multiple tumor lineages auxotrophic for L-arginine. We have also shown that the activation of IL-13-activated macrophages antitumor functions is dependent on the tumor cell recognition by mannose and dectin-1 receptors (C-type Lectin Receptors). Indeed, after recognition, these receptors that are overexpressed by IL-13-activated macrophages, activate Syk-P47phox pathway for ROS production and arachidonic acid-HETEs (hydroxy-eicosatetraenoic acid)-PPAR? axis for arginase activity. Moreover, IL-13 improves T-cell lymphoma regression in tumor-bearing mice through its ability to reprogram TAMs toward cytotoxic effectors. This was supported by a decrease of tumor burden in tumor-bearing mice after adoptive transfer of IL-13-activated macrophages. Finally, we established that IL-13 activates human monocyte-derived macrophages to become tumoricidal against various human tumor cells. This work shows the complexity of the M1/M2 paradigm in the description of pro- and antitumor functions of macrophages. Thus, our findings demonstrate the ability of IL-13 to stimulate macrophage antitumor activities, in the context of T-cell lymphoma. This work also suggests that effective modulation of mannose and dectin-1 receptors by IL-13 might shift the "tumor cells-macrophages" interaction for the host benefit.
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The plasticity of melanoma cell invasiveness / The plasticity of melanoma cell invasivenessGandalovičová, Aneta January 2016 (has links)
and keywords: During metastasis, cancer cells can invade the extracellular matrix using various strategies. When invading individually, they employ either the amoeboid invasion mode, during which the cell body dynamically deforms by enhanced contractility to squeeze through pores within the matrix, or protease dependent mesenchymal migration that takes advantage of the possibility to digest the surrounding matrix. Cells migrating in one mode can actively switch to the other by mesenchymal-amoeboid (MAT) or amoeboid-mesenchymal transitions (AMT). This enables escape mechanisms and considerably complicates anti-metastatic treatment. It is well known that Rho GTPases are master regulators of cytoskeleton re-arrangements and thus, unsurprisingly, play a major role in both invasion modes and can directly drive the transitions. However, upstream activation of these pathways is still largely unclear. This thesis aimed to optimize 3D conditions suitable for studying plasticity of cell invasion in vitro, establish AMT and MAT in melanoma cells based on manipulation of Rho GTPases and verify novel candidates regulating cell invasion plasticity based on previous RNA sequencing of cells before and after MAT. Last, by synthesis of published data, results from sequencing and new findings presented in this...
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(Om) Krisen Kommer! : En antropologisk studie kring krisberedskap i Sverige med fokus på det civila ansvaret.Jimenez, Sofia January 2020 (has links)
This essay serves to investigate how Sweden’s emergency preparedness has moved from primarily being a matter of the state to a matter of the individual. The shift in responsibility has been analysed with the theory of rationalism and the relationship between state and society. The method used was semi-structured interviews done with eight individuals who identify as preppers, to some extent. The emergency preparedness shift to the individual has come with some problematic traits as civilians are used to the state’s authority and care. This has led to majority of people to not be prepared, which became prominent when the Covid-19 pandemic came to Sweden. What is asked from individuals is at least one week of individual preparedness and includes food, water, heat and communication. Information has mainly been distributed by the Authority for Civil Protection and Emergency Preparedness (MSB). Emergency preparedness can therefore be discussed as both reason and emotion.
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THE ROLE OF PROLACTIN RECEPTOR SIGNALING IN LIVER HOMEOSTASIS AND DISEASEJennifer Abla Yanum (11157624) 06 August 2021 (has links)
<p>Functioning as a “powerhouse”, the liver adapts to the
metabolic needs of the body by maintaining a homeostatic balance. Prolactin
receptor (PRLR) has been found
to have a copious existence in the liver. Having established a well-defined role in both reproductive
and endocrine systems, the role of this transmembrane protein in hepatocytes is
yet to be elucidated. Due to its abundant nature, we hypothesized that PRLR is
required for maintaining hepatic homeostasis and plays a role in liver
diseases. To test this hypothesis, we defined two specific aims. The first was
to explore whether PRLR loss-of-function affects liver structure and function
in physiological conditions. The second was to determine whether PRLR is
associated with liver pathology. We deleted the <i>Prlr</i> gene specifically in hepatocytes using a virus-based approach
and evaluated liver function, transcriptome, and activities of downstream signaling
molecules. Due to the absence of PRLR, we found that the urea cycle was
disrupted, concomitant with excessive accumulation of urea in the blood; 133 genes exhibited
differential expression, largely associated with hepatocyte structure,
metabolism, and inflammation; and the activities of STAT3 and 5 were reduced. The
results signify that PRLR indeed plays a homeostatic role in the liver. We also
used <i>Prlr</i><sup>+/-</sup> mice to
assess whether the loss of one allele of the <i>Prlr</i> gene alters maternal hepatic adaptations to pregnancy. As a
result, in the pre-pregnancy state and during the first half of gestation, the
expression of maternal hepatic PRLR protein was reduced approximately by half
owing to <i>Prlr</i> insufficiency. However,
during the second half of pregnancy, we observed compensatory upregulation of
this molecule, leading to minimal
interference in
STAT 3 and 5 signaling and liver size. Contrary to a previous study in the
breast and ovary, our results suggest that one allele of <i>Prlr</i> may be sufficient for the maternal liver to respond to this physiological
stimulus (pregnancy). Furthermore, we examined the expression and activity of
PRLR in fatty as well as cholestatic livers. Using a high fat diet, we induced non-alcoholic
fatty liver disease (NAFLD).
Strikingly and for the first time, we discovered that the short isoform of PRLR
(PRLR-S) was completely inactivated in response to NAFLD, whereas the long isoform
remained unchanged. This finding strongly suggests the involvement of PRLR-S in
lipid metabolism. We also postulate that PRLR-L may be the major regulator of
STAT signaling in the liver, consistent with other reports. Lastly, we induced
extrahepatic cholestasis via bile duct ligation (BDL) in mice. As this liver
disease progressed, the expression of both isoforms of PRLR generally declined
and was surprisingly accompanied by increased STAT 3 and 5 activity. The data
suggests that PRLR participates in this disease progression, with a
disconnection between PRLR signaling and STAT proteins. Collectively, our preliminary
studies suggest that PRLR signaling is required to maintain liver homeostasis
and more prominently, is involved in liver diseases, especially NAFLD. These
findings lay a foundation for our future studies.</p>
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The Role of Prolactin Receptor Signaling in Liver Homeostasis and DiseaseYanum, Jennifer Alba 08 1900 (has links)
Indiana University-Purdue University Indianapolis (IUPUI) / Functioning as a “powerhouse”, the liver adapts to the metabolic needs of the body by maintaining a homeostatic balance. Prolactin receptor (PRLR) has been found to have a copious existence in the liver. Having established a well-defined role in both reproductive and endocrine systems, the role of this transmembrane protein in hepatocytes is yet to be elucidated. Due to its abundant nature, we hypothesized that PRLR is required for maintaining hepatic homeostasis and plays a role in liver diseases. To test this hypothesis, we defined two specific aims. The first was to explore whether PRLR loss-of-function affects liver structure and function in physiological conditions. The second was to determine whether PRLR is associated with liver pathology. We deleted the Prlr gene specifically in hepatocytes using a virus-based approach and evaluated liver function, transcriptome, and activities of downstream signaling molecules. Due to the absence of PRLR, we found that the urea cycle was disrupted, concomitant with excessive accumulation of urea in the blood; 133 genes exhibited differential expression, largely associated with hepatocyte structure, metabolism, and inflammation; and the activities of STAT3 and 5 were reduced. The results signify that PRLR indeed plays a homeostatic role in the liver. We also used Prlr+/- mice to assess whether the loss of one allele of the Prlr gene alters maternal hepatic adaptations to pregnancy. As a result, in the pre-pregnancy state and during the first half of gestation, the expression of maternal hepatic PRLR protein was reduced approximately by half owing to Prlr insufficiency. However, during the second half of pregnancy, we observed compensatory upregulation of this molecule, leading to minimal interference in STAT 3 and 5 signaling and liver size. Contrary to a previous study in the breast and ovary, our results suggest that one allele of Prlr may be sufficient for the maternal liver to respond to this physiological stimulus (pregnancy). Furthermore, we examined the expression and activity of PRLR in fatty as well as cholestatic livers. Using a high fat diet, we induced non-alcoholic fatty liver disease (NAFLD). Strikingly and for the first time, we discovered that the short isoform of PRLR (PRLR-S) was completely inactivated in response to NAFLD, whereas the long isoform remained unchanged. This finding strongly suggests the involvement of PRLR-S in lipid metabolism. We also postulate that PRLR-L may be the major regulator of STAT signaling in the liver, consistent with other reports. Lastly, we induced extrahepatic cholestasis via bile duct ligation (BDL) in mice. As this liver disease progressed, the expression of both isoforms of PRLR generally declined and was surprisingly accompanied by increased STAT 3 and 5 activity. The data suggests that PRLR participates in this disease progression, with a disconnection between PRLR signaling and STAT proteins. Collectively, our preliminary studies suggest that PRLR signaling is required to maintain liver homeostasis and more prominently, is involved in liver diseases, especially NAFLD. These findings lay a foundation for our future studies.
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Vart är Indien på väg? : En beskrivande studie av staten Indiens förändringar i medborgarskapslagenSöder, Julia January 2019 (has links)
No description available.
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Flow cytometric evaluation of STAT phosphorylation in T cell populationBitar, Michael 04 November 2020 (has links)
Intracellular protein phosphorylation is a critical step in cellular activation stimulated by the binding of various ligands to cell surface receptors. This process is initiated by activation of specific protein-tyrosine kinases associated with intracellular domains of the respective ligand receptor. JAK-STATs pathway is one of the main pathways in the cell activation process and given their important role in various PIDs, STATs proteins have been extensively studied in immune function in health and disease.
Therefore, our work has focused on investigating and evaluating STATs activation and establishing flow cytometric methods to assess their phosphorylation to be a surrogate marker as a fast and sensitive diagnostic tool to current methods such as WB.
At the first, we studied STAT1 and STAT3 activation and established a flow cytometric procedure to analyze variations of INF-α- and IL-6-induced STAT1 and STAT3 phosphorylation in T cells from whole blood, respectively (publication ΙΙ). To examine whether our results were specific, the samples were also analyzed by WB in parallel. After that, we validated the normal values of pSTAT1 and pSTAT3 based on 21 healthy adult controls according to an appropriate validation process.
We showed that, in contrast to the conventional methods like WB, our assay offers a diagnostic benefit by avoiding labor and time consumption, with the advantage of achieving an earlier diagnosis, which potentially leads to improve treatment decisions; hence, patient’s outcome (publication ΙΙ).
Furthermore, we verified FCM-based pSTAT1 and pSTAT3 profiling established here in patients group suffering from CMC and HIES. Our results demonstrated that pSTAT1 and pSTAT3 assay is an effective tool to identify and characterize well-known PIDs such as CMC and HIES, respectively (publication ΙΙ).
Next, we introduced a fast and straightforward flow cytometric assay for the assessment of T cell proliferation, based on the staining of phosphorylated STAT5A (publication ΙΙΙ). We showed that pSTAT5A represents an appropriate approach to predict the behavior of T cells upon activation by CD3/CD28 and PHA. FCM-based pSTAT5A profiling is an intracellular flow cytometric method, enabling the early and reliable detection of T cell proliferation without long time incubation (within 24 h instead to 5 days). Importantly, measurement of pSTAT5A represents a new principle to assess T cell proliferation. It reveals important information on T cell biology by using series of kinetics and different kinds of T cell stimulation. For instance: [1] after stimulation via CD3/CD28 and negative pSTAT5A and T cell proliferation, the immune defect could be occurred in the whole signaling cascade (TCR-IL-2 transcription-JAK3-STAT5), [2] After stimulation via external IL-2 and negative pSTAT5A, the immune defect could be localized in the signaling cascade (IL-2R – JAK3 – STAT5), [3] After stimulation via external IL-2 and positive pSTAT5A, the immune defect could be localized in the signaling cascade (TCR - IL-2 transcription) (publication ΙΙΙ).
We showed a strong correlation between the STAT5A phosphorylation and the percentage of dividing cells (publication ΙΙΙ). Later on, we used the measurement established here to investigate whether the phosphorylation of STAT5A is an appropriate candidate for predicting CMV specific T cell proliferation.
It is well-known that CMV specific T cells expand with CMV reactivation and are probably prerequisite for control and protection. We demonstrated that CMV specific pSTAT5A detection represents a fast and straightforward diagnostic tool to assess CMV specific T cell proliferation without requisite several days’ culture (publication ΙV).
Furthermore, we showed a positive correlation between the percentage of pSTAT5A+ T cells vs. (1) CMV-IgG concentrations vs. (2) the percentage of expanded T cells and vs. (3) the percentage of initial CMV specific T cells (publication ΙV).
Finally, we evaluated the diagnostic value of pSTAT5 assay and determined the percentage of pSTAT5A+ T cells cut-off value at which pSTAT5 assay has the greatest diagnostic potency. Our data showed that a cut-off value of 9.1 % could be used to assess CMV specific T cell proliferation with a specificity and sensitivity of 100% and 73%, respectively.
We verified measurement established here by CMV specific T cells stimulation in three selected patients diagnosed with CARMIL2-mutation and suffering from chronic CMV
infection. Our results showed that the complete and the partial deficiency of CMV and CD3/CD28 stimulated pSTAT5A correlated with the complete and the partial deficiency of CMV and CD3/CD28 stimulated T cell proliferation, respectively (publication ΙV).
In conclusion, disorders in JAKs-STATs signal pathways in T cells may result in insufficient response to stimulants. Therefore, FCM-based pSTATs profiling is an effective tool for clinical laboratory diagnostics [1] to understand the susceptibility to recurrent opportunistic infections [2] to rapidly identify T cell proliferation [3] to investigate tumor-specific responses of CD8 T effector and memory cells (56) and finally [4] to identify and distinguish well-known PIDs like CARMIL-2 mutations, CMC, AD-HIES or AR-HIES.
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