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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.
21

Analýza exprese cytokinů u MeLiM prasečího modelu regredujícího melanomu / Cytokine expression in regressive melanoma on porcine MeLiM model

Miltrová, Veronika January 2020 (has links)
Cutaneous melanoma is a very aggressive cancer with increasing incidence. It originates from transformed pigmented skin cells (melanocytes). The main risk factor for melanoma development is exposure to UV light and repeated sunburns. In approximately 10 % of cases, melanoma occurs on hereditary basis. Patients with cutaneous melanoma diagnosed in early stages have very good prognosis, with surgical resection of the primary tumour being mostly sufficient for treatment. In contrast, the advanced melanoma stages with metastases are often progressive and refractory to conventional therapies. Cutaneous melanoma is referred to as an immunogenic tumour that is frequently infiltrated by cells of the immune system. Tumours with immune cell infiltration show better prognosis. Spontaneous regression may occur. Over the last few years, progress has been made in the treatment of melanoma using checkpoints molecules (anti-CTLA-4 and anti-PD-1) to activate patients own immune system to recognize tumour lesions. In the tumour microenvironment, cytokines play an important role, enabling communication between cells and regulation of cell proliferation and migration and thus the tumour development. Cytokines (IL-2, IFNα) can be used in adjuvant therapy of melanoma. This work analysed levels of expressed cytokines in...
22

Betydelsen av interleukin 4 receptorn (IL-4R) i stimulering av lymfom- och leukemiceller

Skog, Emma January 2011 (has links)
Cytokiner eller interleukiner är signalpeptider med låg molekylär vikt somreglerar många viktiga funktioner. De kan delas in i två grupper beroende på deraseffekt på celler. Interleukin 4 (IL-4) till exempel kan tillhöra gruppentillväxtfaktorer medan interleukin 6 (IL-6) kan tillhöra gruppen aktiverings- ellerdifferentieringsfaktorer. IgM-receptorn eller B-cellsreceptorn, BCR, finns på Bcelleroch är membranbundna immunoglobuliner (mIg) som har tvåhuvuduppgifter; att förmedla signaler som styr B-cellens utveckling samt att bindain antigen som sedan ska presenteras för T-celler. I studien aktiverades B-cellermed antikropp mot IgM (anti-IgM) samt rekombinant IL-4. Efter stimuleringanalyserades IL-6 produktionen med enzyme-linked immunosorbent assay(ELISA). Syftet med studien var att karakterisera uttrycket av IL-4 receptorn pålymfom- och leukemiceller med flödescytometri och polymeras chain reaction(PCR) samt produktion av IL-6 med ELISA. ELISA-analysen visade att tvåcellinjer, stimulerade Sp53 och stimulerade samt kontroller av WaC3CD5+, gaven ökning av IL-6 produktionen. Vid jämförelse med ELISA-resultaten ochflödescytometri-analyserna ser man att WaC3CD5+ som producerat storamängder IL-6, har en liten andel IL-4 receptorer på cellytan. Resultatet av PCRanalysenvisar att det var framförallt Sp53 som fick höga mängder IL-4R mRNA,men även I83, U2932 och WaC3CD5+ fick positiva resultat. Resultaten i dennastudie är preliminära och för att få mer säkerställda resultat krävs att alla analysergörs om ett antal gånger för att få ett mer tillförlitligt resultat. / Cytokines or interleukins are signal peptides of low molecular weight, whichregulates many important functions. They can roughly be divided into two groupsor divisions due to their effect on cells. Interleukin 4 (IL-4), for example, belongsto the group growth factors while interleukin-6 (IL-6) belongs to the groupactivation or differentiation factors. IgM receptors or B cell receptors, BCR, areexpressed on B cells and are membrane-bound immunoglobulins (mIg) and havetwo main functions: to convey signals that control B cell activation and to bindantigen which will then be presented to T cells. In the study B cells were activatedwith antibodies against IgM (anti-IgM) and recombinant IL-4. After stimulationthe IL-6 production was analysed by enzyme-linked immunosorbent assay(ELISA). The purpose of this study was to characterize the expression of IL-4receptor in lymphoma and leukemia cells by flow cytometry and polymerasechain reaction (PCR) and furthermore the production of IL-6 by ELISA. ELISAanalysis showed that two cell lines, stimulated Sp53 and stimulated and control ofWaC3CD5+, resulted in an increased IL-6 production. When comparing ELISAresults and flow cytometry assays, it can be seen that WaC3CD5+, whichproduced large amounts of IL-6, has a small percentage of IL-4 receptors on thecell surface. The results of the PCR analysis shows that particularly Sp53displayed high amounts of IL-4 mRNA, but also I83, U2932 and WaC3CD5+were positive for IL-4 mRNA. The results of this study are preliminary, and to getmore trustworthy results, all analyses have to be repeated to get more reliableresults.
23

Homeostatic Regulation of Interleukin-4-Mediated Cell Signaling

Chakraborty, Rikhia 21 December 2009 (has links)
No description available.
24

The Role Of Chemokines and Dendritic Cells In Regulation of IL-4 and Fungal Immunity

Szymczak, Wendy A. 13 April 2010 (has links)
No description available.
25

Signaling Cross-Talk Regulating the Expression of Arginase 1 in Murine Macrophages

Surace, Michael Joseph 23 April 2010 (has links)
Macrophages can be activated by a variety of extracellular signals to polarize to either the M1 (inflammatory and antimicrobial) or to the M2 (wound repair and inflammation resolution) phenotype. Expression of arginase 1 in macrophages is a key marker of the M2 phenotype. Arginase 1 expression is induced by interleukin 4 (IL-4), a cytokine secreted by Th2 helper cells. All-trans retinoic acid (ATRA) is a product of metabolism of dietary retinol (vitamin A). In a manner analogous to hormones, ATRA binds to nuclear receptors in cells and influences gene expression and cell physiology. ATRA is important in the resolution of inflammation systemically and on the cellular level, however it has not been linked to M2 activation or arginase 1 expression. Testing the hypothesis that ATRA can induce arginase 1 in macrophages either directly or indirectly, it was found that ATRA alone cannot cause murine bone marrow-derived macrophages (BMDM) to activate in the M2 phenotype (as indicated by arginase 1 expression), however it can dramatically potentiate induction of arginase 1 expression and activity by IL-4. This is the first observation positively linking ATRA to arginase 1. Lipopolysaccharide (LPS), is a conserved structural component of the outer membrane of Gram negative bacteria, and a potent pyrogen. In metabolic endotoxemia, LPS concentration in the blood is slightly elevated, and over the long term this contributes to diverse inflammatory diseases such as atherosclerosis, obesity, and diabetes. LPS promotes the M1 phenotype and suppresses the M2 phenotype, but its contribution at low doses such as those found in metabolic endotoxemia are not well studied. In order to investigate mechanisms of LPS suppression at low doses, mice deficient in IRAK1 and tollip, key mediators or proinflammatory LPS signaling, were used to study IL-4, ATRA, and LPS crosstalk. LPS suppression of arginase 1 was found to be dependent on IRAK1 and tollip, but only at low doses of LPS. / Ph. D.
26

Reconnaissance de surfaces de protéines par des foldamères aromatiques / Protein surface recognition by aromatic foldamers

Stupfel, Marine 22 December 2010 (has links)
Les interactions protéine-protéine jouent un rôle primordial dans de nombreux processus biologiques. L’importance de ces interactions a suscité le développement de nouvelles approches thérapeutiques qui ciblent ces complexes protéiques. Nous nous proposons d’inhiber ces interactions en élaborant une stratégie de reconnaissance de surfaces de protéines par des molécules synthétiques de taille intermédiaire, les foldamères d’oligoquinoline. Ces composés se replient en des structures hélicoïdales stables dont chaque élément constitutif peut être fonctionnalisé pour permettre des propriétés de reconnaissance de surface de protéine.Afin de valider ce concept, l’interaction entre l’anhydrase carbonique humaine de type II (HCAII) et son inhibiteur N-benzyl-4-sulphamoylbenzamide (SBB) a été sélectionnée comme système modèle. Plusieurs étapes de synthèse ont permis de concevoir de nouveaux foldamères capables de former un complexe avec l’enzyme par l’intermédiaire de l’inhibiteur SBB et d’un espaceur approprié. Chaque complexe protéine-foldamère a été co-cristallisé et l’affinité des interactions a été caractérisée par dichroïsme circulaire induit et par résonance plasmonique de surface. Ce concept a ensuite été appliqué à une interaction protéine-protéine d’intérêt thérapeutique, le complexe IL-4/IL-4R, dans le cadre du programme européenFOLDAPPI (FP7-PEOPLE-IAPP-2008). / Protein-protein interactions play key roles in many biological processes as well as in many diseases. The importance of these interactions has led to the development of new therapeutic approaches that target protein interfaces. We have developed a protein surface recognition strategy to inhibit protein-protein interactions by using intermediate size organicmolecules called oligoquino line foldamers, that result in very stable and well defined helical structures. These helical backbones are used as templates within each building block can be modulated to allow protein surface recognition.In order to validate this concept, the well-characterized interaction between the enzyme human carbonic anhydrase II (HCAII) and its N-benzyl-4-sulphamoylbenzamide (SBB) inhibitor was selected as a model system. Multi-steps synthesis allowed functionalization of new foldamers able to bind to the enzyme through the SBB inhibitor attached by a spacer.Each foldamer–protein complex was cocrystallized and the affinity of the interactions was assayed using both induced circular dichroïsm and surface plasmon resonance. The concept of using a foldamer against protein-protein interaction was then applied to a protein complex of therapeutic interest, IL-4/IL-4R, within the European FOLDAPPI program (FP7-PEOPLEIAPP- 2008).
27

O circuito p38MAPK/MSK1 influencia o período inicial de diferenciação Th1/2. / The p38MAPK/MSK1 circuit influences the early stages of activation and differentiation of Th1/2 cells.

Bombardieri, Cíntia Raquel 12 December 2007 (has links)
O sistema imune dos mamíferos forma uma complexa rede de populações celulares especializadas e vias de sinalização extremamente reguladas. Linfócitos T naïve podem diferenciar-se após encontro com o antígeno em pelo menos duas sub-populações distintas, Th1 ou Th2, sendo que o papel do circuito p38MAPK/MSK1 durante este período inicial de ativação não é completamente entendido. Linfócitos T CD4+ naïve humanos foram estimulados in vitro em condições não-polarizantes (Tnp), Th1 ou Th2, na presença de inibidor específico da p38MAPK. As células ativadas e mantidas em condições diferenciadoras Th1 ou Th2 na presença do inibidor SB203580, apresentaram menor produção de IFN-<font face=\"symbol\">g e maior produção de IL-4. Através do bloqueio do RNAm da MSK1 por siRNA, observamos o mesmo efeito resultante da inibição da p38MAPK, fato que foi confirmado em experimentos com linfócitos T de camundongos MSK1-deficientes. A alteração da produção das citocinas características de cada população parece ser decorrente da alteração da expressão da IL12R<font face=\"symbol\">b2 e IL4R-<font face=\"symbol\">a dos receptores de citocinas da IL-12 e IL-4, respectivamente. Desta forma, os nossos dados sugerem que o circuito p38MAPK/MSK1 participa do processo de ativação dos linfócitos T mantidos em condições diferenciadoras Th1/2. / The mammalian immune system form a complex network of highly regulated signaling pathways and populations of specialized cells. After meeting with the antigen naïve T cells differentiate into at least two distinct sub-populations, Th1 or Th2, and the role of the circuit p38MAPK/MSK1 during this initial period of activation is not completely understood. Human CD4+ T lymphocytes were stimulated in vitro under non-polarized, Th1 or Th2 conditions, in the presence of a specific p38MAPK inhibitor. The cells activated and differentiated under Th1 or Th2 condition in the presence of inhibitor SB203580, had decreased production of IFN-<font face=\"symbol\">g and increased IL-4. By silencing MSK1 through siRNA, we observed the same effect due to inhibition of p38MAPK, an observation that was confirmed in experiments with T lymphocytes from mice deficient of MSK1. The change in the production of cytokines appears to be a result of altered expression of IL12R-<font face=\"symbol\">b2 and IL4R<font face=\"symbol\">a receptors of the cytokines IL-12 and IL-4, respectively. Taken together, our data suggest that the circuit p38MAPK/MSK1 plays a key role in the activation of human T cells maintained under Th1/2 differentiation conditions.
28

Genový polymorfismus Th1/Th2 cytokinů u pacientek s děložní myomatózou / Th1/Th2 cytokine gene polymorphisms in patients with urine fibroid

Sosna, Ondřej January 2011 (has links)
Background: Uterine fibriod (UF) or leiomyoma is the most frequent benign tumour upon lower genital tract and represents the most frequent indication for hysterectomy. The aetiology remains still unknown. The genetic factors contributing for the development of UF are being intensively investigated. The aim of our study was to look for possible genetic markers which could be used as prognostic tools for evaluation of an increased risk for development of UF. Methods: The study group enrolled 102 patients diagnosed with UF and 145 healthy controls. Ultrasonographic examination of the pelvis was performed and a single blood sample was taken in all women. Histological verification followed the surgery in the patient group. The principal of the cytokine gene polymorphisms detection is based on PCR reaction with sequence-specific primers. Results: A large spectrum of Th1/Th2 cytokine gene polymorphisms in patients with uterine fibroid was compared with control group. The frequencies of the majority of tested cytokine gene SNP in the patient cohort were not statistically different from the cytokine SNP in the control group. However, an intriguing association between polymorphisms of the IL-4 gene promotor at positions -590 C/T and -33 C/T, and the risk of leiomyoma was observed. The CC genotype of IL-4 at position...
29

Expressão de genes da resposta imune em bovinos infestados com carrapatos (Boophilus microplus)

Belo, Vanessa de Almeida 15 February 2008 (has links)
Submitted by Renata Lopes (renatasil82@gmail.com) on 2016-10-14T12:30:34Z No. of bitstreams: 1 vanessadealmeidabelo.pdf: 412659 bytes, checksum: 2be0607436379c3a9ca0f2415972f9be (MD5) / Approved for entry into archive by Adriana Oliveira (adriana.oliveira@ufjf.edu.br) on 2016-10-22T13:05:05Z (GMT) No. of bitstreams: 1 vanessadealmeidabelo.pdf: 412659 bytes, checksum: 2be0607436379c3a9ca0f2415972f9be (MD5) / Made available in DSpace on 2016-10-22T13:05:05Z (GMT). No. of bitstreams: 1 vanessadealmeidabelo.pdf: 412659 bytes, checksum: 2be0607436379c3a9ca0f2415972f9be (MD5) Previous issue date: 2008-02-15 / Nos países tropicais, as perdas causadas pela infestação de carrapatos em bovinos acarretam um grande impacto no sistema de produção animal. Recentes estudos têm mostrado a importância de fatores genéticos ligados a resistência a carrapato em Bos taurus indicus e Bos taurus taurus e que as citocinas têm um papel crítico na prevenção ou progressão de doenças. O objetivo desse trabalho foi avaliar os níveis de expressão dos genes IL-10 e IL-4 relacionados ao perfil imunológico Th2 associado à susceptibilidade ao carrapato e os genes IL-2 e IFN- relacionados ao perfil imunológico Th1 associado à resistência ao parasito. Além destes genes, analisou-se o perfil de expressão do gene TLR-2, importante no processo de reconhecimento de patógenos e os genes IL-8 e TNF-α importantes no processo inflamatório inicial. Seis animais mais resistentes e seis animais mais susceptíveis de uma população F2 de 332 animais, originária do cruzamento de animais F1(½ Holandês: ½ Gir), foram selecionados baseado na contagem de carrapatos e valor genético. Amostras de tecido foram coletadas de pele no 5° e 12° dias após a infestação para extração de RNA total. As PCRs em tempo real foram realizadas usando o gene GAPDH como controle endógeno. Os animais resistentes e susceptíveis apresentaram aumento de expressão do gene IL-10 no 5° (p<0,01) e 12 ° dias após a infestação (p<0,05). O gene IL-2, nos animais resistentes e susceptíveis, no 5° dia após a infestação não apresentou alteração da expressão sendo que 12° dia, em ambos os grupos de animais, este gene passou a ser mais expresso em relação ao animal controle sugerindo um perfil de resposta imunológica do tipo de Th2 nos animais resistentes e susceptíveis nos primeiros dias após a infestação. O gene IL-4 apresentou uma tendência ao aumento de expressão nos animais resistentes e susceptíveis em relação ao controle, sendo o perfil Th2 sugerido atribuído a IL-10 produzida por linfócitos T regulatórios (p>0,05). O gene TNF- apresentou aumento de expressão nos animais susceptíveis no 5° dia após a infestação com posterior diminuição no 12° dia após a infestação (p<0,05). Nos animais resistentes não foi observada alteração da expressão deste gene, isto sugere que ele possa estar mais atuante no início do processo inflamatório, logo após a fixação do carrapato. A mesma observação estende-se para o gene IL-8, em que não foi verificada alteração de expressão nos animais resistentes, embora nos animais susceptíveis este gene apresentou diminuição da expressão no 12° dia após a infestação (p<0,05). Quanto ao gene IFN-, não houve diferença de expressão entre os animais resistentes e susceptíveis, sendo que este gene parece não estar relacionado ao mecanismo de resistência. O gene TLR-2 apresentou diminuição da expressão em ambos os grupos de animais. Estes resultados sugerem que a resposta imune adquirida avaliada neste trabalho não apresenta papel preponderante no mecanismo de resistência e que resposta imune inata poderia está envolvida no mecanismo de resistência ao carrapato. Portanto, avaliação da resposta imunológica horas após a fixação do carrapato poderia nos fornecer resultados mais conclusivos. / In tropical countries losses caused by tick infestation in cattle lead to a major impact on animal production systems. Recent studies have shown the importance of genetic factors linked to tick resistance in Bos indicus and Bos taurus as well as the critical role in the prevention or progression of diseases mediated by cytokines. The aim of this work was to evaluate gene expression of IL-10 and IL-4 in relation to tick susceptibility associated with the Th2 profile and gene expression of IL-2 and IFN- in relation to tick resistance associated with the Th1 profile. In addition, the expression of TLR-2, important in the process the recognition of pathogens, and TNF-α and IL-8 genes, important in the initial inflammatory process, were evaluated. Six tick-resistant and six tick-susceptible animals from a F2 population of 332 animals, originated from the cross of F1 animals (½ Holstein: ½ Gir), were selected based on tick count and breeding value for tick resistance. Skin biopsies were collected in the 5th and 12th days after tick infestation. The GAPDH was used as endogenous control to normalize the amount of starting cDNA target in the real-time PCR assay. Both resistant and susceptible animals showed increased gene expression of IL-10 in the 5th and 12th days after infestation in relation to control animal (p<0.05). The IL-2 gene showed no change of expression in the 5th day after infestation for the resistant and susceptible animals. In the 12th post infestation, both resistant and susceptible animals showed increased gene expression in relation to control animal. These results suggest an enhancement of Th2 profile through the increase of IL-10 mRNA levels and a possible inhibition of the Th1 pattern in both groups (resistant and susceptible) starting 5 days after infestation and return to normal by day 12. Despite our results suggest the occurrence of the Th2 profile, the susceptible and resistant animals did not show variation on gene expression for IL-4 in relation to control animal. The susceptible animals showed increased expression of TNF-α in the 5th day after infestation. However, in the 12th day post infestation it was noted a decrease in the gene expression level. The resistant animals showed no change in the expression of this gene in relation to control animals suggesting that TNF-α could be more actively expressed in the early steps of the inflammatory process. Similarly, the resistant animals showed no variation in the expression of IL-8 while the susceptible animals showed increased expression in the 12th day post infestation. There were no differences of expression between resistant and susceptible animals in relation to IFN-γ what suggests that this gene might not be involved in the resistance mechanism. The TLR-2 gene showed decreased expression in both resistant and susceptible animals (p<0.05). Finally, there was no difference in expression between susceptible and resistant animals in relation to all selected genes in the 5th and 12th days after infestation. These results suggest that the acquired immunity evaluated in this work might not have preponderant role in the resistance mechanism. The innate immunity might be playing a major role in the bovine tick resistance/susceptibility mechanism in early hours after infestation.
30

O circuito p38MAPK/MSK1 influencia o período inicial de diferenciação Th1/2. / The p38MAPK/MSK1 circuit influences the early stages of activation and differentiation of Th1/2 cells.

Cíntia Raquel Bombardieri 12 December 2007 (has links)
O sistema imune dos mamíferos forma uma complexa rede de populações celulares especializadas e vias de sinalização extremamente reguladas. Linfócitos T naïve podem diferenciar-se após encontro com o antígeno em pelo menos duas sub-populações distintas, Th1 ou Th2, sendo que o papel do circuito p38MAPK/MSK1 durante este período inicial de ativação não é completamente entendido. Linfócitos T CD4+ naïve humanos foram estimulados in vitro em condições não-polarizantes (Tnp), Th1 ou Th2, na presença de inibidor específico da p38MAPK. As células ativadas e mantidas em condições diferenciadoras Th1 ou Th2 na presença do inibidor SB203580, apresentaram menor produção de IFN-<font face=\"symbol\">g e maior produção de IL-4. Através do bloqueio do RNAm da MSK1 por siRNA, observamos o mesmo efeito resultante da inibição da p38MAPK, fato que foi confirmado em experimentos com linfócitos T de camundongos MSK1-deficientes. A alteração da produção das citocinas características de cada população parece ser decorrente da alteração da expressão da IL12R<font face=\"symbol\">b2 e IL4R-<font face=\"symbol\">a dos receptores de citocinas da IL-12 e IL-4, respectivamente. Desta forma, os nossos dados sugerem que o circuito p38MAPK/MSK1 participa do processo de ativação dos linfócitos T mantidos em condições diferenciadoras Th1/2. / The mammalian immune system form a complex network of highly regulated signaling pathways and populations of specialized cells. After meeting with the antigen naïve T cells differentiate into at least two distinct sub-populations, Th1 or Th2, and the role of the circuit p38MAPK/MSK1 during this initial period of activation is not completely understood. Human CD4+ T lymphocytes were stimulated in vitro under non-polarized, Th1 or Th2 conditions, in the presence of a specific p38MAPK inhibitor. The cells activated and differentiated under Th1 or Th2 condition in the presence of inhibitor SB203580, had decreased production of IFN-<font face=\"symbol\">g and increased IL-4. By silencing MSK1 through siRNA, we observed the same effect due to inhibition of p38MAPK, an observation that was confirmed in experiments with T lymphocytes from mice deficient of MSK1. The change in the production of cytokines appears to be a result of altered expression of IL12R-<font face=\"symbol\">b2 and IL4R<font face=\"symbol\">a receptors of the cytokines IL-12 and IL-4, respectively. Taken together, our data suggest that the circuit p38MAPK/MSK1 plays a key role in the activation of human T cells maintained under Th1/2 differentiation conditions.

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