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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.
391

Insights Into the Regulatory Requirements for T Follicular Helper Cell Development

Powell, Michael D. 22 April 2019 (has links)
During the course of an immune response, CD4+ T helper cells differentiate into a number of subsets including: T helper 1 (TH1), TH2, TH17, and T follicular helper (TFH) populations. The functional diversity of CD4+ T effector cells results in a coordinated, pathogen-specific immune response. For example, the production of IFNγ by TH1 cells is vital for the clearance of intracellular pathogens, while TFH cell engagement with cognate B cells is required for germinal center (GC) formation and the generation of pathogen- and vaccine- induced antibody production. The development of CD4+ subsets is contingent on extracellular signals, in the form of cytokines, and downstream transcriptional networks responsible for promoting the unique gene expression profile for each subset while simultaneously suppressing alternative cell fates. However, the exact composition of, and stage-specific requirements for, these environmental cytokines and transcription factor networks in the governance of TFH cell differentiation remain incompletely understood. The work in this dissertation seeks to understand how cell-extrinsic cytokine signals and cell-intrinsic transcription factor activities are integrated to properly regulate TFH cell development. Here, we demonstrate that in response to decreased IL-2 and constant IL-12 signaling, T helper 1 (TH1) cells upregulate a TFH-like phenotype, including expression of the TFH lineage defining transcription factor Bcl-6. Intriguingly, our work established that signals from IL-12 were required for both the differentiation and function of this TFH-like population. Mechanistically, IL-12 signals are propagated through both STAT3 and STAT4, leading to the upregulation of the TFH associated genes Bcl6, Il21, and Icos, correlating with increased B cell helper activity. Conversely, exposure of these TFH-like cells to IL-7 results in the STAT5-dependent repression of Bcl-6 and subsequent inhibition of the TFH phenotype. Finally, we describe a novel regulatory mechanism wherein STAT3 and the Ikaros zinc finger transcription factors Ikaros and Aiolos cooperate to regulate Bcl-6 expression in these TFH-like cells. Collectively, the work in this dissertation significantly advances our understanding of the regulatory mechanisms that govern TFH cell differentiation, setting the basis for the rational design of novel immunotherapeutic strategies and increasingly effective vaccines. / Ph. D. / Specialized cells called T helper cells serve as a critical interface between the innate (first line of defense) and adaptive (specialized and long-term) immune systems. During the course of an infection, T helper cells are responsible for orchestrating the immune-mediated elimination of invading viruses, bacteria, and parasites. This wide breadth of functionality is achieved through the formation of distinct T helper subsets including T helper 1 (TH1), TH2, TH17, and T follicular helper (TFH) populations. Individual subsets have distinct developmental requirements and have unique functions within the immune system. For example, TFH cells are required for the production of effective antibodies that recognize invading pathogens, leading to their subsequent elimination. This naturally occurring process is the basis for a number of modern medical therapies including vaccination. Conversely, aberrant generation of antibodies that recognize host tissues can result in the onset of various autoimmune diseases including lupus, multiple sclerosis, and crohn’s disease. Due to the importance of TFH cells to human health, there is intense interest in understanding how these cells are formed. It is recognized that the generation of these therapeutically important immune cells is mediated by numerous cell-extrinsic andintrinsic influences, including proteins in their cellular environment called cytokines, and important proteins inside of the cell called transcription factors. However, as this is a complicated and multi-step process, many questions remain regarding the identity of these cytokines and transcription factors. The work in this dissertation seeks to understand how cellextrinsic cytokine signals and cell-intrinsic transcription factor activities are integrated to properly regulate TFH cell development. Collectively, this body of work significantly advances our understanding of the regulatory mechanisms that govern TFH cell differentiation, setting the basis for the rational design of novel immunotherapeutic strategies and increasingly effective vaccines.
392

Childhood Maltreatment is Associated with Adult Depression: Is Inflammation to Blame?

Lewis, Jasmine 12 December 2022 (has links)
By 2030 major depression is predicted to be the leading cause of disease burden in the world; as such, it is critical to understand factors that contribute to the development of depression. The social signal transduction theory of depression hypothesizes that adversity and social threat upregulate pro-inflammatory biomarkers leading to depression. The current study examined whether pro-inflammatory biomarkers (interleukin-6, interleukin-8, c-reactive protein, and tumor necrosis factor alpha) mediate the association between various types of childhood maltreatment (physical abuse, sexual abuse, emotional abuse, physical neglect, emotional neglect) and adult depression symptoms in a sample of 740 adults (372 female; Mage= 51.6 years, SD = 13.6) who provided retrospective report of childhood maltreatment as part of the Midlife in the United States (MIDUS) Refresher Biomarker study. Additionally, it explored whether these relations differ for males versus females. A series of linear regression analyses were run in SPSS; separate models were run for each form of childhood maltreatment and for interleukin-6, interleukin-8, c-reactive protein, and tumor necrosis factor-alpha. The results showed that childhood maltreatment is a robust predictor of adulthood depression; however, this association did not differ between biological sexes. In addition, only interleukin-6 was shown to partially mediate the association between childhood maltreatment and adulthood depression. These findings highlight the need to explore the use of interleukin-6 to screen for depression in youth. / M.S. / By 2030 major depression is predicted to be the leading cause of disease burden in the world; as such, it is critical to understand factors that contribute to the development of depression. It has been hypothesized that adversity and social threat activate pro-inflammatory biomarkers, which are proteins that can detect inflammation in the body, leading to depression. The current study examined whether several pro-inflammatory biomarkers explain the association between several types of childhood maltreatment (physical abuse, sexual abuse, emotional abuse, physical neglect, emotional neglect) and adult depression symptoms in a sample of 740 adults (372 female; Mage= 51.6 years, SD = 13.6) who provided report of past experiences of childhood maltreatment. Additionally, it explored whether these relations differ for males versus females. The results showed that childhood maltreatment is a robust predictor of adulthood depression for males and females. Of the inflammatory biomarkers examined, only interleukin-6 was shown to partially explain the association between childhood maltreatment and adulthood depression symptoms. These findings highlight the need to explore the use of interleukin-6 to screen for depression in youth.
393

Qualidade de vida, qualidade de sono, transporte mucociliar, citocinas inflamatórias e endotipos na rinite alérgica e na rinossinusite crônica / Quality of life, sleep quality, mucociliary transport, inflammatory cytokines and endotypes in allergic rhinitis and chronic rhinosinusitis

Fonseca, Luciana Mazoti Lopes da 05 December 2018 (has links)
Introdução: A rinite alérgica (RA) e a rinossinusite crônica (RSC) são doenças inflamatórias nasais com prevalência alta e crescente. Estima-se que 15,5% dos norte-americanos tenham RSC, e estudo recente encontrou prevalência de 5,51% na cidade de São Paulo, enquanto a RA acomete entre 10 e 20% da população mundial. Apesar de terem mecanismos fisiopatológicos distintos, em ambas, há recrutamento de células de defesa, principalmente linfócitos T, e produção de citocinas inflamatórias. Esses mediadores variam não apenas entre as doenças, mas também entre as populações acometidas, e seu conhecimento é importante para o diagnóstico correto e direcionamento da terapia escolhida. Objetivos: Mapear os mediadores inflamatórios presentes no lavado nasal e no condensado do ar exalado na RSC e na RA, avaliando possíveis biomarcadores da doença, e analisar o endotipo inflamatório dos pacientes estudados. Além disso, avaliar a qualidade de vida, o nível de obstrução nasal, a qualidade do sono dos pacientes afetados, o transporte mucociliar e coletar material para análise de pH, contagem de células totais e seu diferencial. Pacientes e métodos: Estudo exploratório prospectivo em corte transversal, sendo os pacientes divididos em quatro grupos: 1) Grupocontrole com pacientes sem queixas; 2) Pacientes com RA com prick test positivo; 3) Pacientes com RSC com polipose; e 4) Pacientes com RSC sem polipose. Todos os pacientes responderam a quatro questionários: 20-Item Sino-Nasal Outcome Test (SNOT-20p), Nasal Obstruction Symptom Evaluation (NOSE), o Índice de Qualidade do Sono de Pittsburgh (Pittsburgh Sleep Quality Index - PSQI-BR) e o questionário para triagem e diagnóstico da asma da European Community Respiratory Health Survey (ECRHS). Foi realizado exame físico, incluindo endoscopia nasal (escore de Lund- Kennedy modificado) e, nos pacientes com RSC, avaliação da tomografia computadorizada (TC) de face (escore de Lund-Mackay). Foi também avaliado o transporte mucociliar por meio do teste da sacarina. Coletou-se o condensado do ar exalado para análise do pH e lavado nasal para avaliação do pH, da presença de citocinas e da celularidade (total e diferencial). Foi avaliada a presença de IL-4, IL-5, IL-8, IL-17A, IL-22, TNF-Alfa e IFN-Gama no lavado nasal e IL-5, IL-17A, IL-22 e IFN-Gama no condensado do ar exalado. Resultados: Os pacientes com RSC apresentaram escores significativamente piores nos questionários de obstrução nasal (NOSE, p < 0,01) e qualidade de vida (SNOT-20p, p < 0,01) quando comparados aos controles, e tanto os pacientes com RSC quanto com RA apresentaram pior qualidade do sono (PSQI-BR, p < 0,01). O escore de extensão de Lund- Mackay foi mais elevado nos pacientes com RSC com polipose (p < 0,02). O teste da sacarina apresentou tempo mais prolongado no grupo RSC com polipose (p < 0,01). O pH do condensado do ar exalado não diferiu entre os grupos. O grupo RSC com polipose apresentou tanto diferença do pH (p < 0,01) quanto da contagem de células totais do lavado nasal (p < 0,01) quando comparado ao grupo-controle, porém sem diferença na contagem diferencial. IFN? do condensado foi mais elevado no grupo RA em comparação ao grupo C (p=0,05), enquanto IL-5 foi mais alto no grupo RSC com polipose quando comparado ao grupo RSC sem polipose (p=0,02). Os pacientes foram, então, divididos em endotipos, segundo os grupos descritos por Tomassen et al., sendo que endotipos são os subtipos da doença definidos funcionalmente e patologicamente por mecanismos moleculares distintos. Conclusão: Pacientes com RSC apresentaram escores piores nos questionários de qualidade de vida (SNOT-20p e NOSE), o que, em parte, poderia ser atribuído à pior qualidade do sono apresentada tanto por estes pacientes quanto pelos portadores de RA. O teste da sacarina evidenciou pior transporte mucociliar nos pacientes com RSC com polipose. Não houve diferença do pH do condensado do ar exalado, sugerindo que, apesar de interessante na avaliação das vias aéreas inferiores, este pode não ser um bom teste para análise das vias aéreas superiores. Foram encontradas alterações significantes tanto do pH quanto da contagem de células totais do lavado nasal do grupo com RSC com polipose, sem, no entanto, haver diferença na contagem diferencial. Dos 17 pacientes com RSC com perfil completo de citocinas, 12 se encaixam em endotipos já descritos, sendo que, dos cinco restantes, dois apresentam o mesmo perfil, podendo indicar um novo subgrupo / Introduction: Allergic rhinitis (AR) and chronic rhinosinusitis (CRS) are nasal inflammatory diseases with high and increasing prevalence. It is estimated that 15.5% of Americans have CRS, and a recent study found a prevalence of 5.51% in the city of São Paulo, while AR affects between 10 and 20% of the world population. Although they have distinct pathophysiological mechanisms, in both there is recruitment of defense cells, mainly T lymphocytes, and production of inflammatory cytokines. These mediators vary not only between diseases but also among affected populations, and their knowledge is important for the correct diagnosis and targeting of the therapy chosen. Objectives: To map the inflammatory mediators present in the nasal wash and the exhaled breath condensate in the CRS and AR, evaluating possible biomarkers of this diseases, and to analyze the inflammatory endotype of the patients studied. In addition, assess quality of life, level of nasal obstruction, sleep quality of affected patients, mucociliary transport and collect samples for pH analysis, total cell count and its differential. Patients and Methods: Prospective cross-sectional exploratory study, divided into four groups: 1) Control group with patients without complaints 2) Patients with AR with prick test positive 3) Patients with CRS with polyps 4) Patients with CRS without polyps. All patients responded to four questionnaires: 20-Item Sino-Nasal Outcome Test (SNOT-20p), Nasal Obstruction Symptom Evaluation (NOSE), Pittsburgh Sleep Quality Index (PSQI-BR) and European Community Respiratory Health Survey (ECRHS) questionnaire for screening and diagnosis of asthma. A physical examination was performed, including nasal endoscopy (modified Lund-Kennedy score) and, in patients with CRS, a computerized tomography (Lund-Mackay score) evaluation. The mucociliary transport was also evaluated through the saccharin test. The exhaled breath condensate was collected for pH analysis and the nasal wash for evaluation of pH, cytokines and cellularity (total and differential). The presence of IL-4, IL-5, IL-17, IL-17A, IL-22, TNF-Alfa and IFN-Gama in the nasal wash and IL-5, IL-17A, IL-22 and IFN-Gama in the exhaled breath condensate. Results: Patients with CRS had significantly worse scores in the nasal obstruction questionnaire (NOSE, p < 0.01) and quality of life questionnaire (SNOT-20p, p < 0.01) when compared to controls, and both patients with CRS and AR presented worse sleep quality (PSQI-BR, p < 0.01). The Lund-Mackay extension score was higher in patients with CRS with polyps (p < 0.02). The saccharin test showed longer time in the CSR group with polyps (p < 0.01). The pH of the exhaled breath condensate did not differ between groups. The CRS with polyps group presented both pH difference (p < 0.01) and higher total nasal wash cell count (p < 0.01) when compared to the control group, but with no difference in the differential count (p = 0.05), while IL-5 was higher in the CRS group with polyps when compared to the RSC without polyps group (p = 0.02). Patients were then divided into endotypes according to the groups described by Tomassen et al, Endotypes are the subtypes of the disease defined functionally and pathologically by distinct molecular mechanisms. Conclusions: Patients with CRS presented worse scores on quality of life questionnaires (SNOT-20p and NOSE), which could be attributed in part to the poorer quality of sleep presented by both patients with CRS and AR. The saccharin test evidenced worse mucociliary transport in patients with CRS with polyps when compared with control group. There was no difference in the pH of the exhaled breath condensate, suggesting that, although interesting in the evaluation of the lower airways, this may not be a good test for analyzing the upper airways. Significant alterations were found in both pH and total nasal wash cell count in the CSR group with polyposis, but there was no difference in the differential count. Of the 17 patients with CRS with complete cytokine profile, 12 fit into already described endotypes, and of the remaining five, two have the same profile, which may indicate a new subgroup
394

Qualidade de vida, qualidade de sono, transporte mucociliar, citocinas inflamatórias e endotipos na rinite alérgica e na rinossinusite crônica / Quality of life, sleep quality, mucociliary transport, inflammatory cytokines and endotypes in allergic rhinitis and chronic rhinosinusitis

Luciana Mazoti Lopes da Fonseca 05 December 2018 (has links)
Introdução: A rinite alérgica (RA) e a rinossinusite crônica (RSC) são doenças inflamatórias nasais com prevalência alta e crescente. Estima-se que 15,5% dos norte-americanos tenham RSC, e estudo recente encontrou prevalência de 5,51% na cidade de São Paulo, enquanto a RA acomete entre 10 e 20% da população mundial. Apesar de terem mecanismos fisiopatológicos distintos, em ambas, há recrutamento de células de defesa, principalmente linfócitos T, e produção de citocinas inflamatórias. Esses mediadores variam não apenas entre as doenças, mas também entre as populações acometidas, e seu conhecimento é importante para o diagnóstico correto e direcionamento da terapia escolhida. Objetivos: Mapear os mediadores inflamatórios presentes no lavado nasal e no condensado do ar exalado na RSC e na RA, avaliando possíveis biomarcadores da doença, e analisar o endotipo inflamatório dos pacientes estudados. Além disso, avaliar a qualidade de vida, o nível de obstrução nasal, a qualidade do sono dos pacientes afetados, o transporte mucociliar e coletar material para análise de pH, contagem de células totais e seu diferencial. Pacientes e métodos: Estudo exploratório prospectivo em corte transversal, sendo os pacientes divididos em quatro grupos: 1) Grupocontrole com pacientes sem queixas; 2) Pacientes com RA com prick test positivo; 3) Pacientes com RSC com polipose; e 4) Pacientes com RSC sem polipose. Todos os pacientes responderam a quatro questionários: 20-Item Sino-Nasal Outcome Test (SNOT-20p), Nasal Obstruction Symptom Evaluation (NOSE), o Índice de Qualidade do Sono de Pittsburgh (Pittsburgh Sleep Quality Index - PSQI-BR) e o questionário para triagem e diagnóstico da asma da European Community Respiratory Health Survey (ECRHS). Foi realizado exame físico, incluindo endoscopia nasal (escore de Lund- Kennedy modificado) e, nos pacientes com RSC, avaliação da tomografia computadorizada (TC) de face (escore de Lund-Mackay). Foi também avaliado o transporte mucociliar por meio do teste da sacarina. Coletou-se o condensado do ar exalado para análise do pH e lavado nasal para avaliação do pH, da presença de citocinas e da celularidade (total e diferencial). Foi avaliada a presença de IL-4, IL-5, IL-8, IL-17A, IL-22, TNF-Alfa e IFN-Gama no lavado nasal e IL-5, IL-17A, IL-22 e IFN-Gama no condensado do ar exalado. Resultados: Os pacientes com RSC apresentaram escores significativamente piores nos questionários de obstrução nasal (NOSE, p < 0,01) e qualidade de vida (SNOT-20p, p < 0,01) quando comparados aos controles, e tanto os pacientes com RSC quanto com RA apresentaram pior qualidade do sono (PSQI-BR, p < 0,01). O escore de extensão de Lund- Mackay foi mais elevado nos pacientes com RSC com polipose (p < 0,02). O teste da sacarina apresentou tempo mais prolongado no grupo RSC com polipose (p < 0,01). O pH do condensado do ar exalado não diferiu entre os grupos. O grupo RSC com polipose apresentou tanto diferença do pH (p < 0,01) quanto da contagem de células totais do lavado nasal (p < 0,01) quando comparado ao grupo-controle, porém sem diferença na contagem diferencial. IFN? do condensado foi mais elevado no grupo RA em comparação ao grupo C (p=0,05), enquanto IL-5 foi mais alto no grupo RSC com polipose quando comparado ao grupo RSC sem polipose (p=0,02). Os pacientes foram, então, divididos em endotipos, segundo os grupos descritos por Tomassen et al., sendo que endotipos são os subtipos da doença definidos funcionalmente e patologicamente por mecanismos moleculares distintos. Conclusão: Pacientes com RSC apresentaram escores piores nos questionários de qualidade de vida (SNOT-20p e NOSE), o que, em parte, poderia ser atribuído à pior qualidade do sono apresentada tanto por estes pacientes quanto pelos portadores de RA. O teste da sacarina evidenciou pior transporte mucociliar nos pacientes com RSC com polipose. Não houve diferença do pH do condensado do ar exalado, sugerindo que, apesar de interessante na avaliação das vias aéreas inferiores, este pode não ser um bom teste para análise das vias aéreas superiores. Foram encontradas alterações significantes tanto do pH quanto da contagem de células totais do lavado nasal do grupo com RSC com polipose, sem, no entanto, haver diferença na contagem diferencial. Dos 17 pacientes com RSC com perfil completo de citocinas, 12 se encaixam em endotipos já descritos, sendo que, dos cinco restantes, dois apresentam o mesmo perfil, podendo indicar um novo subgrupo / Introduction: Allergic rhinitis (AR) and chronic rhinosinusitis (CRS) are nasal inflammatory diseases with high and increasing prevalence. It is estimated that 15.5% of Americans have CRS, and a recent study found a prevalence of 5.51% in the city of São Paulo, while AR affects between 10 and 20% of the world population. Although they have distinct pathophysiological mechanisms, in both there is recruitment of defense cells, mainly T lymphocytes, and production of inflammatory cytokines. These mediators vary not only between diseases but also among affected populations, and their knowledge is important for the correct diagnosis and targeting of the therapy chosen. Objectives: To map the inflammatory mediators present in the nasal wash and the exhaled breath condensate in the CRS and AR, evaluating possible biomarkers of this diseases, and to analyze the inflammatory endotype of the patients studied. In addition, assess quality of life, level of nasal obstruction, sleep quality of affected patients, mucociliary transport and collect samples for pH analysis, total cell count and its differential. Patients and Methods: Prospective cross-sectional exploratory study, divided into four groups: 1) Control group with patients without complaints 2) Patients with AR with prick test positive 3) Patients with CRS with polyps 4) Patients with CRS without polyps. All patients responded to four questionnaires: 20-Item Sino-Nasal Outcome Test (SNOT-20p), Nasal Obstruction Symptom Evaluation (NOSE), Pittsburgh Sleep Quality Index (PSQI-BR) and European Community Respiratory Health Survey (ECRHS) questionnaire for screening and diagnosis of asthma. A physical examination was performed, including nasal endoscopy (modified Lund-Kennedy score) and, in patients with CRS, a computerized tomography (Lund-Mackay score) evaluation. The mucociliary transport was also evaluated through the saccharin test. The exhaled breath condensate was collected for pH analysis and the nasal wash for evaluation of pH, cytokines and cellularity (total and differential). The presence of IL-4, IL-5, IL-17, IL-17A, IL-22, TNF-Alfa and IFN-Gama in the nasal wash and IL-5, IL-17A, IL-22 and IFN-Gama in the exhaled breath condensate. Results: Patients with CRS had significantly worse scores in the nasal obstruction questionnaire (NOSE, p < 0.01) and quality of life questionnaire (SNOT-20p, p < 0.01) when compared to controls, and both patients with CRS and AR presented worse sleep quality (PSQI-BR, p < 0.01). The Lund-Mackay extension score was higher in patients with CRS with polyps (p < 0.02). The saccharin test showed longer time in the CSR group with polyps (p < 0.01). The pH of the exhaled breath condensate did not differ between groups. The CRS with polyps group presented both pH difference (p < 0.01) and higher total nasal wash cell count (p < 0.01) when compared to the control group, but with no difference in the differential count (p = 0.05), while IL-5 was higher in the CRS group with polyps when compared to the RSC without polyps group (p = 0.02). Patients were then divided into endotypes according to the groups described by Tomassen et al, Endotypes are the subtypes of the disease defined functionally and pathologically by distinct molecular mechanisms. Conclusions: Patients with CRS presented worse scores on quality of life questionnaires (SNOT-20p and NOSE), which could be attributed in part to the poorer quality of sleep presented by both patients with CRS and AR. The saccharin test evidenced worse mucociliary transport in patients with CRS with polyps when compared with control group. There was no difference in the pH of the exhaled breath condensate, suggesting that, although interesting in the evaluation of the lower airways, this may not be a good test for analyzing the upper airways. Significant alterations were found in both pH and total nasal wash cell count in the CSR group with polyposis, but there was no difference in the differential count. Of the 17 patients with CRS with complete cytokine profile, 12 fit into already described endotypes, and of the remaining five, two have the same profile, which may indicate a new subgroup
395

Étude du rôle de l'interleukine-32 dans l'infection à VIH-1

Kouassi, N'Guessan Pascale F. 07 1900 (has links)
Les progresseurs lents du VIH-1 sont de rares sujets asymptomatiques pendant plusieurs années sans thérapie antirétrovirale. Parmi ces sujets à progression lente vers le SIDA, il est possible qu’un sous-groupe perde le contrôle de leur infection après plusieurs années de contrôle. Notre laboratoire a analysé l’expression différentielle de différentes protéines et voies moléculaires associées à la perte de contrôle de l’infection: l’interleukine-32 (IL-32) est une cytokine pro-inflammatoire dont le niveau des isoformes alpha et delta a significativement diminué chez les progresseurs lents lors de la perte de contrôle. Par ailleurs, des études antérieures ont attribué, de façon intrigante, à l’IL-32 aussi bien des propriétés anti-VIH-1 que des propriétés immunosuppressives induisant un environnement propice à la réplication du VIH-1. Ce projet de maitrise s’est penché sur l’implication de l’IL-32 dans la progression de l’infection à VIH-1 avec un accent particulier sur les progresseurs lents. Nous avons principalement mesuré les niveaux d’IL-32 des sujets séropositifs comparativement aux sujets VIH négatif et estimé les fonctions de cette cytokine à travers des études longitudinales et de corrélation. Nous avons observé que l’IL-32 total demeure plus élevé chez les séropositifs comparativement aux sujets VIH négatif. Également, l’infection par le VIH-1 entraine une augmentation du niveau d’IL-32 total. De plus, après une année de thérapie antirétrovirale, les taux plasmatiques d’IL-32 total demeurent significativement plus élevés que ceux des sujets VIH négatif. Comme attendu, le taux d’IL-32 total augmente lors de la perte de contrôle de l’infection chez les progresseurs lents. Une forte concentration plasmatique d’IL-32 total coïncide avec: 1) une augmentation du taux plasmatique de sCD14 et de la cytokine pro-inflammatoire IL-6, 2) une baisse du compte cellulaire CD4 et une augmentation de la charge virale. Un taux plasmatique élevé de CCL5 pourrait prédire une faible concentration d’IL-32 total. L’isoforme alpha de l’IL-32 est plus élevée dans le plasma des sujets VIH négatif tandis que l’IL-32 gamma semble induire un environnement pro-inflammatoire et immunosuppressif. Il ressort à l’issue de ces observations que l’augmentation de l’IL-32 total est associée à la progression de l’infection à VIH-1 et pourrait constituer un biomarqueur permettant d’apprécier le pronostic de cette infection. / HIV-1 slow progressors constitute a rare population of subjects who remain asymptomatic for many years without antiretroviral therapy. Among this population, some individuals will lose control of their infection after several years of immunological control. Our laboratory has analyzed the differential expression profile of various proteins and molecular pathways associated with the loss of control of HIV infection. The pro-inflammatory cytokine interleukin-32 alpha and delta isoforms significantly decreased in slow progressors as they were losing control of their infection. Furthermore, previous studies have attributed to IL-32 both antiviral property against HIV-1 and immunosuppressive properties that can induce an environment conducive to HIV-1 replication. This project addresses the role of IL-32 in HIV-1 disease progression with a particular emphasis on slow progressors. We compared the levels of IL-32 in HIV-1 positive versus HIV-1 negative subjects and evaluated the role of this cytokine using longitudinal studies. We observed that levels of IL-32 remains higher in HIV-positive compared to HIV-negative subjects. Also, HIV-1 infection leads to increased level of IL-32. In addition, after one year of antiretroviral therapy, IL-32 plasma levels remain significantly higher than those of HIV-negative subjects. As expected, the levels of IL-32 increased as slow progressors lost control of their infection. A high plasma concentration of IL-32 predicts: 1) an increase in plasma levels of sCD14 as well as pro-inflammatory cytokine IL-6, 2) a decrease in CD4 cell count and an increase in viral load. High plasma CCL5 predicted a low concentration of IL-32. The alpha isoform of IL-32 is elevated in the plasma of HIV negative subjects while IL-32 gamma appears to induce a pro-inflammatory and immunosuppressive environment. We conclude that increased IL-32 levels are associated with progression of HIV-1 disease and could be used as a biomarker for assessing HIV-1 prognosis.
396

Étude sur le rôle de SIGIRR chez les cas pédiatriques dans la maladie de Crohn

Sagala, Patrick 01 1900 (has links)
No description available.
397

Efeito do tratamento com IL-3, IL-7 OU IL-9 em camundongos experimentalmente infectados com Trypanosoma cruzi

Alves, Rosiane Nascimento 17 September 2015 (has links)
Fundação de Amparo a Pesquisa do Estado de Minas Gerais / Chagas disease, caused by the protozoan Trypanosoma cruzi, is ranked as the most serious parasitic disease in Latin America and has become a worldwide problem. A bulk of studies substantiates that Th1-associated cytokines are essential elements in early resistance against the parasite and are associated with the development of the chronic cardiac form. Although cytokines have a key role in the immune response against T. cruzi, little is known about IL-3, IL-7 and IL-9 in this context. Then the aim of this study was to analyze the role of IL-3, IL-7 and IL-9 in the acute phase of T. cruzi experimental infection. For this purpose, parameters indicative of improvement in clinical status of the animals both infected and treated as just treated were studied, such as: morbidity, mortality and histopathology. The amount of cardiac mast cells and the serum cytokines profile were also evaluated. Our data revealed that the treatment with IL-3, IL-7 or IL-9 did not alter the clinical parameters analyzed or the amount of cardiac mast cells in mice infected with T. cruzi. However the treatment with IL-3 decreased the cardiac T. cruzi-induced inflammation and the treatment with IL-7 increased serum levels of IL-5 in infected animals. In addition, the treatment with IL-9 increased the serum levels of Th1 cytokine profile (IL-2, IFN-y and TNF-α) and decreased cardiac fibrosis in infected animals, suggesting a possible protective role of this cytokine in this context. Taken together, our results underline the importance of these cytokines in modulation of T. cruzi infection. Since studies involving IL-3, IL-7 and IL-9 activity during Chagas disease are critical in understanding the parasite control process and the protective and/or harmful action of these cytokines in the host. In addition, understanding of the immunological mechanisms mediated by these cytokines that are involved in disease development may contribute to the establishment of new therapeutic interventions to prevent Chagas disease and treat their symptomatic forms. / A Doença de Chagas, causada pelo protozoário Trypanosoma cruzi, é classificada como a doença parasitária mais grave da América Latina e tornou-se um problema mundial. A maior parte dos estudos confirma que as citocinas de perfil Th1 são elementos essenciais na resistência precoce contra o parasita e estão associadas ao desenvolvimento da forma cardíaca crônica. Embora as citocinas tenham um papel chave na resposta imune contra T. cruzi, pouco se sabe a respeito da função de IL-3, IL-7 e IL-9 neste contexto. Assim, o objetivo deste estudo foi analisar o papel destas citocinas na fase aguda da infecção experimental com T. cruzi. Para isto, parâmetros indicativos de melhora clínica dos animais tanto infectados e tratados como apenas tratados foram estudados, tais como: morbidade, mortalidade e histopatologia. A quantidade de mastócitos cardíacos e o perfil de citocinas séricas também foram avaliados. Os dados revelaram que o tratamento com IL-3, IL-7 ou IL-9 não alterou os parâmetros clínicos analisados nem a quantidade de mastócitos cardíacos nos camundongos infectados com T. cruzi. No entanto, o tratamento com IL-3 diminuiu a inflamação cardíaca T. cruzi-induzida e o tratamento com IL-7 aumentou os níveis séricos de IL-5 nos animais infectados. Além disso, o tratamento com IL-9 aumentou os níveis séricos das citocinas de perfil Th1 (IL-2, IFN-y e TNF-α) e diminuiu a fibrose cardíaca nos animais infectados, sugerindo um possível papel protetor desta citocina neste contexto. Em suma, os nossos resultados demonstram a importância destas citocinas na modulação da infecção por T. cruzi. Já que estudos envolvendo a atividade de IL-3, IL-7 e IL-9 durante a doença de Chagas são fundamentais na compreensão sobre o processo de controle parasitário e da ação protetora e/ou prejudicial dessas citocinas no hospedeiro. Além disso, o entendimento dos mecanismos imunológicos mediados por estas citocinas que estão envolvidos no desenvolvimento da doença pode contribuir para o estabelecimento de novas intervenções terapêuticas a fim de prevenir a doença de Chagas e tratar suas formas sintomáticas / Doutor em Imunologia e Parasitologia Aplicadas
398

Efeito da via de sinalizaÃÃo slam sobre cÃlulas t na resposta in vitro à leishmania braziliensis / Immune cells activation is modulated by balancing the signals triggered by a variety of cell surface receptors, including receptor activators, co-stimulating receptors and inhibitory receptors. Receptor-related signaling molecule in lymphocyte activation (SLAM) influences the immune cell activation. In this study we investigated the role of SLAM in immune response of cutaneous leishmaniasis caused by L. braziliensis, as well as if the response of individuals high (HP) or low (LP) IFN-&#947; producers is modulated by SLAM signaling pathway. Peripheral blood monocuclear cells (PBMC) isolated from 43 health individuals were cultured in vitro with anti-SLAM, rIFN-&#947;, rIL-12 and phytohemagglutinin in the presence or in the absence of L. braziliensis. It was found that L. braziliensis promoted a significantly reduced SLAM expression in T cells, after 120 h of cultured, possibly indicating activation of this pathway in the initial immune response. SLAM expression behaved differently in HP and LP groups. In LP group, L. braziliensis did not modify SLAM expression in T cells in early immune response. The effect of anti-SLAM on SLAM pathway reduced the expression of this protein in the early stages of the immune response of PBMC stimulated with L. braziliensis. After 120 h the effect of anti-SLAM did not alter CD3+SLAM+ expression in both groups. The proinflammatory cytokines, rIFN-&#947; and rIL-12, present in the microenvironment with L. braziliensis, reduced SLAM expression only in HP group after 6 h of culture and did not change this response after 120 h. Anti-SLAM at a concentration of 10 &#956;g/ml presented no effect on production of cytokines IFN-&#947; and IL-13 in both groups, but significantly increased IL-10 production in the HP group. Furthermore anti-SLAM associated with L. braziliensis and rIFN-&#947; simultaneously did not modify IFN-&#947;, IL-13 and IL-10 productions. Anti-SLAM associated with L. braziliensis and rIL-12 simultaneously induced an increase of IFN-&#947; in LP group, and increased IL-13 in HP group. These results suggest that in vitro immune response of PBMC exposed to L. braziliensis, the SLAM signaling pathway acts in modulating Th1 response in HP group and induces a condition of temporary immunosuppression in LP group, not previously described in literature.

Zirlane Castelo Branco Coelho 28 May 2011 (has links)
nÃo hà / A ativaÃÃo das cÃlulas do sistema imunolÃgico à modulada atravÃs dos sinais acionados por uma diversidade de receptores de superfÃcie celular, incluindo os receptores ativadores, receptores coestimuladores e receptores inibidores. Receptores relacionados à molÃcula sinalizadora na ativaÃÃo do linfÃcito (SLAM) tÃm influÃncia na ativaÃÃo imunolÃgica celular. Neste trabalho, investigou-se a funÃÃo de SLAM na resposta imunolÃgica à Leishmania braziliensis, e se a resposta de indivÃduos alto (AP) ou baixo (BP) produtores de IFN-&#947; seria modulada pela via de sinalizaÃÃo SLAM. CÃlulas monocucleadas do sangue perifÃrico (CMSP) de 43 indivÃduos foram bloqueadas com &#945;-SLAM, rIFN-&#947;, rIL-12 e fitohemaglutinina, apÃs estimulaÃÃo com L. brazilensis. Verificou-se que L. braziliensis promoveu uma significante reduÃÃo da expressÃo de SLAM nas cÃlulas T, com 120h de cultivo, possivelmente indicando ativaÃÃo desta via na resposta imunolÃgica inicial. A expressÃo de SLAM se comportou de modo diferenciado nos indivÃduos AP e BP. Nos indivÃduos BP, L. braziliensis nÃo alterou a expressÃo de SLAM nas cÃlulas T, na fase inicial da resposta imunolÃgica. O bloqueio da via de SLAM com &#945;-SLAM reduziu significativamente a expressÃo desta proteÃna nos primeiros momentos da resposta imunolÃgica das CMSP estimuladas com L. braziliensis. O bloqueio com &#945;-SLAM, avaliado com 120 horas, nÃo alterou a expressÃo de CD3+SLAM+, em ambos os grupos. As citocinas proinflamatÃrias, rIFN-&#947; e rIL-12, presentes no microambiente com L. braziliensis, reduziram a expressÃo de SLAM apenas em indivÃduos AP com 6h de sensibilizaÃÃo e nÃo modificaram esta resposta com 120h de cultivo, na presenÃa do antÃgeno. O bloqueio com &#945;-SLAM, na concentraÃÃo de 10&#956;g/ml, nÃo interferiu na produÃÃo das citocinas IFN-&#947; e IL-13, em ambos os grupos, entretanto aumentou de forma significativa a produÃÃo de IL-10 em indivÃduos AP. O bloqueio da via de SLAM associado à L. braziliensis e rIFN-&#947; nÃo modificou a produÃÃo de IFN-&#947;, IL-13 e IL-10. O bloqueio da via de SLAM associado à L. braziliensis e rIL-12 induziu aumento de IFN-&#947;, nos indivÃduos BP, e aumento de IL-13, nos indivÃduos AP. Os resultados deste trabalho sugerem que, na resposta in vitro de CMSP, sensibilizadas com L. braziliensis, a via de sinalizaÃÃo SLAM atua na modulaÃÃo da resposta Th1 em indivÃduos AP e induz uma condiÃÃo de imunossupressÃo temporÃria nos indivÃduos BP, nÃo descrita anteriormente na literatura. / Immune cells activation is modulated by balancing the signals triggered by a variety of cell surface receptors, including receptor activators, co-stimulating receptors and inhibitory receptors. Receptor-related signaling molecule in lymphocyte activation (SLAM) influences the immune cell activation. In this study we investigated the role of SLAM in immune response of cutaneous leishmaniasis caused by L. braziliensis, as well as if the response of individuals high (HP) or low (LP) IFN-&#947; producers is modulated by SLAM signaling pathway. Peripheral blood monocuclear cells (PBMC) isolated from 43 health individuals were cultured in vitro with anti-SLAM, rIFN-&#947;, rIL-12 and phytohemagglutinin in the presence or in the absence of L. braziliensis. It was found that L. braziliensis promoted a significantly reduced SLAM expression in T cells, after 120 h of cultured, possibly indicating activation of this pathway in the initial immune response. SLAM expression behaved differently in HP and LP groups. In LP group, L. braziliensis did not modify SLAM expression in T cells in early immune response. The effect of anti-SLAM on SLAM pathway reduced the expression of this protein in the early stages of the immune response of PBMC stimulated with L. braziliensis. After 120 h the effect of anti-SLAM did not alter CD3+SLAM+ expression in both groups. The proinflammatory cytokines, rIFN-&#947; and rIL-12, present in the microenvironment with L. braziliensis, reduced SLAM expression only in HP group after 6 h of culture and did not change this response after 120 h. Anti-SLAM at a concentration of 10 &#956;g/ml presented no effect on production of cytokines IFN-&#947; and IL-13 in both groups, but significantly increased IL-10 production in the HP group. Furthermore anti-SLAM associated with L. braziliensis and rIFN-&#947; simultaneously did not modify IFN-&#947;, IL-13 and IL-10 productions. Anti-SLAM associated with L. braziliensis and rIL-12 simultaneously induced an increase of IFN-&#947; in LP group, and increased IL-13 in HP group. These results suggest that in vitro immune response of PBMC exposed to L. braziliensis, the SLAM signaling pathway acts in modulating Th1 response in HP group and induces a condition of temporary immunosuppression in LP group, not previously described in literature.
399

Makropinozytose und Interleukin-1β-Sekretion nach Kalziumstimulation von Monozyten und Makrophagen von Patienten mit rheumatoider Arthritis und Kontrollprobanden

Hahn, Magdalena 04 February 2020 (has links)
Monocytes and macrophages are mediator cells of cartilage and bone erosion in the synovia of rheumatoid arthritis (RA) patients due to secretion of the inflammatory cytokine Interleukin-1β (IL-1β). Calcium, phosphate and fetuin are liberated from the affected bone matrix, and the formation of calciproteinparticles (CPPs) is likely. IL-1β production in monocytes in vitro is stimulated by high concentrations of extracellular calcium. Additionally, the rise of extracellular calcium concentrations leads to increased macropinocytosis in mononuclear phagocytes. Flow cytometry analyses in this study show that peripheral blood monocytes from patients with RA perform more calcium stimulated macropinocytosis of the fluorescent dye calcein than monocytes from healthy donors. Stimulation of monocytes with calcium and preformed CPPs leads to more IL-1β production, quantified using ELISA, by monocytes from RA patients. Experiments with macrophages show similar results. Furthermore calcium-stimulated macropinocytosis and IL-1β secretion are significantly positively correlated. However, there was no connection of in vitro findings and the severity of RA in patients.:Abbildungsverzeichnis IV Tabellenverzeichnis VI Abkürzungsverzeichnis VII 1 Einleitung 1 1.1 Rheumatoide Arthritis 1 1.1.1 Epidemiologie und Klinik der rheumatoiden Arthritis 1 1.1.2 Ätiopathogenese der rheumatoiden Arthritis 1 1.2 Monozyten und Makrophagen 3 1.2.1 Inflammasomaktivierung und Interleukin-1β-Sekretion in Monozyten und Makrophagen 4 1.2.2 Makropinozytose in Monozyten und Makrophagen 6 1.2.3 Beitrag der Monozyten und Makrophagen zur rheumatoiden Arthritis 7 1.3 Kalzium – lokale Dysregulation trotz systemischer Regulation 9 1.3.1 Entstehung von Kalziumproteinpartikeln 10 1.3.2 Kurzportrait des G-Protein-gekoppelten Kalziumrezeptors CaSR 11 2 Fragestellungen 13 3 Forschungsdesign, Material und Methoden 15 3.1 Forschungsdesign 15 3.2 Materialien 15 3.2.1 Laborgeräte 16 3.2.2 Verbrauchsmaterialien 17 3.2.3 Materialien und Chemikalien 17 3.2.4 Medien, Lösungen und Puffer 19 3.2.5 Stimulanzien und Inhibitoren 20 3.2.6 Fluoreszenzfarbstoffe 20 3.2.7 Software 20 3.3 Methoden 21 3.3.1 Separation von PBMCs mittels Ficolldichtegradientenzentrifugation 21 3.3.2 Separation von Monozyten mittels negativer Magnetseparation 22 3.3.3 Differenzierung von Monozyten zu Makrophagen in Zellkulturbeuteln 23 3.3.4 Makropinozytose von Monozyten und Makrophagen in der Durchflusszytometrie 23 3.3.4.1 Makropinozytose von Calcein in Monozyten 24 3.3.4.2 Makropinozytose fluoreszenzgefärbter Kalziumproteinpartikel in Monozyten und Makrophagen 25 3.3.4.3 Inhibition der Makropinozytose in Monozyten 26 3.3.4.4 Auswertung der am Durchflusszytometer generierten Rohdaten mit FlowJo 26 3.3.5 Makropinozytose von Monozyten in der Fluoreszenzmikroskopie 28 3.3.6 Bestimmung der Interleukin-1β-Produktion von Monozyten und Makrophagen mittels ELISA 29 3.3.7 Erhebung des DAS28 33 3.3.8 Bestimmung von Laborparametern 33 3.4 Statistische Auswertung 33 4 Ergebnisse 35 4.1 Charakterisierung der Kohorten 35 4.2 Vorversuche zur Auswahl eines geeigneten Fluoreszenzfarbstoffes für die Detektion der Makropinozytose 37 4.3 Stimulation von Monozyten mit Kalzium zur Makropinozytose und Interleukin-1β-Produktion 39 4.3.1 Kalziumstimulierte Calceinaufnahme von Monozyten 39 4.3.2 Kalziumstimulierte Interleukin-1β-Produktion von Monozyten 44 4.4 Stimulation von Monozyten mit Kalzium zur Makropinozytose und Interleukin-1β-Produktion unter Zugabe von Kalziumproteinpartikeln 47 4.4.1 Kalziumstimulierte Aufnahme fluoreszierender Kalziumproteinpartikel 47 4.4.2 Kalziumstimulierte Interleukin-1β-Produktion in Monozyten unter Zugabe von Kalziumproteinpartikeln 51 4.5 Stimulation von Makrophagen mit Kalzium zur Makropinozytose und Interleukin-1β-Produktion 53 4.5.1 Kalziumstimulierte Makropinozytose von fluoreszierenden Kalziumproteinpartikeln in Makrophagen 53 4.5.2 Kalziumstimulierte Interleukin-1β-Produktion mit und ohne Zugabe von Kalziumproteinpartikeln in Makrophagen 54 4.5.3. Visualisierung von Monozyten und Makrophagen nach 16 Stunden Inkubation 57 4.6 Korrelation zwischen kalziumstimulierter Makropinozytose und Interleukin-1β-Sekretion 59 5 Diskussion 61 5.1 Kalziumstimulierte Makropinozytoseaktivität von Monozyten und Makrophagen 61 5.2 Kalziumstimulierte Interleukin-1β-Sekretion von Monozyten und Makrophagen 64 5.2.1 Auswirkung der Phosphatkonzentration im Zellkulturmedium auf die kalziumstimulierte Interleukin-1β-Sekretion von Monozyten und Makrophagen 65 5.2.2 Kalziumstimulierte Interleukin-1β-Sekretion von Monozyten und Makrophagen von RA-Patienten und Kontrollprobanden 66 5.3 Zusammenhang von kalziumstimulierter Makropinozytose und Interleukin-1β-Sekretion in Monozyten und Makrophagen von RA-Patienten und Kontrollprobanden 70 5.4 Ausblick und offene Fragen 71 6 Zusammenfassung der Arbeit 73 8 Erklärung über die eigenständige Abfassung der Arbeit 88 9 Danksagung 89
400

Periplasmic Delivery of Biologically Active Human Interleukin-10 in Escherichia coli via a Sec-Dependent Signal Peptide

Pöhlmann, Christoph, Brandt, Manuela, Mottok, Dorothea S., Zschüttig, Anke, Campbell, John W., Blattner, Frederick R., Frisch, David, Gunzer, Florian 18 March 2014 (has links) (PDF)
Interleukin-10 (IL-10) is a potent anti-inflammatory cytokine, with therapeutic applications in inflammatory bowel disease. For the in situ delivery of IL-10 by Escherichia coli as carrier chassis, a modified transporter was designed with the ability to secrete biologically active IL-10. De novo DNA synthesis comprised a 561-bp fragment encoding the signal sequence of the E. coli outer membrane protein F fused in frame to an E. coli codon-optimized mature human IL-10 gene under control of a T7 promoter. The construct was overexpressed in E. coli laboratory strains, E. coli BL21 (DE3) and E. coli MDS42:T7. The mean concentrations of human IL-10 in the periplasm and culture supernatant of E. coli BL21 (DE3) were 355.8 ± 86.3 and 5.7 ± 1.7 ng/ml, respectively. The molecular mass of the recombinant E. coli-derived human IL-10 was 19 kDa, while under non-reducing conditions the native IL-10 dimer could be demonstrated. Reduction of tumor necrosis factor-α secretion in lipopolysaccharide-stimulated mouse macrophages and detection of the activated form of the transcription factor signal transducer and activator of transcription protein 3 proved the biological activity of the bacteria-produced human IL-10. / Dieser Beitrag ist mit Zustimmung des Rechteinhabers aufgrund einer (DFG-geförderten) Allianz- bzw. Nationallizenz frei zugänglich.

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