• Refine Query
  • Source
  • Publication year
  • to
  • Language
  • 239
  • 96
  • 64
  • 56
  • 26
  • 24
  • 16
  • 11
  • 9
  • 3
  • 2
  • 2
  • 1
  • 1
  • 1
  • Tagged with
  • 670
  • 88
  • 74
  • 71
  • 69
  • 67
  • 67
  • 62
  • 59
  • 59
  • 58
  • 54
  • 51
  • 48
  • 43
  • 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.
71

Treating the changing face of Western medicine : pharmacological interventions on the Jak/STAT pathway in diabetic complications and its relationship to ageing

Hull, William John January 2017 (has links)
Ageing and diabetes are two major healthcare concerns that used to be regarded as problems of the Western world but are now of increasing concern in developing nations. Treating elderly patients with diabetes poses issues for clinicians due to often complex, preexisting drug regimes. Research targeted at the development of novel drugs that have multiple effects on diabetes could go some way towards reducing polypharmacy in these patients. Here I present evidence that the oral Jak1/3 inhibitor, baricitinib, has effects on multiple aspects of diabetes. Baricitinib has been suggested to be a strong anti-inflammatory given the role Jak plays in transducing cytokine signals to elicit immune cell activation and maturation. Baricitinib was found to reduce urinary albumin to creatinine ratio and mesangial expansion in mice on an experimental high-fat diet with a diabetic metabolic profile when compared with naïve, non-diabetic mice. This reduction in renal impairment from diabetes was not found with a large reduction in proinflammatory cytokines and instead appears to be as a result of a direct effect on the cells of the mesangium. Baricitinib also reduced the circulating levels of cholesterol with a positive effect on the LDL: HDL ratio of diabetic mice. This reduction in cholesterol appears to be because of the abolition of GLP- 1 signalling, initiating an increase in blood insulin, preventing lipid flux and inhibiting LDL formation. Both of these changes in key diabetic complications were not accompanied by an increase in sensitivity to insulin compared with vehicle treated diabetic mice. These results show that baricitinib has a beneficial effect on two key aspects of the diabetic condition but that it does not modify insulin sensitivity itself. Baricitinib may represent a potential treatment for these diabetes-associated pathologies but only in combination with traditional anti-diabetic treatments.
72

The induction and regulation of CD4 T cells following respiratory syncytial virus infection

Weiss, Kayla Ann 01 May 2014 (has links)
Respiratory syncytial virus (RSV) is the leading cause of lower respiratory tract infections in young children. RSV induces variable disease severities in infected children. Severe cases of RSV-induced disease result in bronchiolitis, with a subset of children going onto develop long-term airway morbidities. The host antiviral T cell response is believed to contribute to the severity of pulmonary disease following acute RSV infection. However recent work has questioned the relative proportion of T cells that migrate into the lung tissue following a respiratory virus infection. Using in vivo intravascular antibody labeling, >80% of antigen-specific effector T cells were found to remain in the pulmonary vasculature following an intratracheal infection with the systemic viral pathogen lymphocytic choriomeningitis virus (LCMV). Therefore, I determined the proportion of RSV-specific CD4 T cells located within the lung tissue following infection. In contrast to recent reports with LCMV-specific CD8 T cells, I found approximately 85% of RSV-specific CD4 T cells were located within the lung tissue, indicating that the vast majority of virus-specific effector CD4 T cells are located within the lung tissue and not in the pulmonary vasculature following an acute RSV infection. Genetic variations can occur in the circulating RSV strains both within and between infectious seasons. Therefore, I questioned if different RSV strains could induce differential CD4 T cell responses. I demonstrate that RSV strains induce differential CD4 T helper responses, which are associated with the differential activation of the innate immune response. The RSV line 19 strain induced the early production of the pro-inflammatory cytokines IL-1Β and IL-6 resulting in an increased Th17 response as compared to the RSV strains A2 and 2-20. Blockade and/or neutralization of IL-1Β and IL-6 inhibited the ability of RSV line 19 to induce a Th17 response. These results demonstrate that RSV strains can differentially activate innate immunity that subsequently influences the type of adaptive immune response. This in part may contribute to differential RSV pathogenesis and the development of long-term airway morbidities observed in humans. IL-10 is a pleotropic cytokine able to suppress the adaptive immune response. Because the host adaptive immune response is believed to contribute to RSV-induced pulmonary disease, I evaluated the role of IL-10 in modulating the RSV-specific immune response. I found that IL-10 protein levels in the lung were increased following acute RSV infection with maximum production corresponding to the peak of the virus-specific T cell response. Multiple populations of CD4 T cells accounted for the majority of IL-10 produced in the lung including Foxp3+ Tregs, Foxp3- CD4 T cells that co-produce IFN-Γ, and Foxp3- CD4 T cells that do not co-produce IFN-Γ. Furthermore, RSV-induced disease severity was increased in both the absence of IL-10 and following IL-10 receptor blockade as compared to control mice. I also observed an increase in the magnitude of the RSV-induced CD8 and CD4 T cell response that correlated with increased disease severity following IL-10 receptor blockade. IL-10 receptor blockade during acute RSV infection altered CD4 T cell subset distribution, resulting in a significant increase in IL-17A-producing CD4 T cells and a concomitant decrease in Foxp3+ regulatory T cells. These results demonstrate that IL-10 plays a critical role in modulating the adaptive immune response to RSV by limiting T-cell-mediated pulmonary inflammation and injury. Overall, my data demonstrate that RSV-specific CD4 T cells migrate into the lung tissue with their differentiation influenced by the strain-specific activation of innate immune response. IL-10 is then produced by CD4 T cells to regulate the RSV-specific T cell responses and inhibit virus-induced immunopathology. My data indicate that there are multiple targets for immunotherapy for individuals with severe RSV-induced disease.
73

Identification of Paclitaxel-induced Cytokines in Breast Carcinoma Cells

Yang, Jie 01 August 2019 (has links)
Inflammatory cytokines and chemokines are known to promote tumor cell survival, invasion, the formation of blood and lymphatic vessels, and hence, metastasis. We previously showed that a pro-inflammatory pathway regulated by Toll-like Receptor-4 (TLR4) can be activated in human breast cancer (BC) cell lines by a clinical chemotherapeutic drug, paclitaxel (PXL). Prior data showed that PXL treatment of TLR4+ tumors in vivo increased inflammation and tumor spread. Here, we used two BC models based on MDA-MB-231 and HCC1806 cell lines. Transcript expression of 123 cytokines in vitro and in vivo was determined by qRT-PCR. We found that 18 and 26 cytokines were upregulated by nanoparticle albumin-bound paclitaxel (nab-PXL) in 231TLR4+ cells and in 1806TLR4+ cells, respectively. Upregulation of cytokines was observed in cultured cells and in tumor models in vivo. Furthermore, fourteen cytokines (11.3% of total) were induced by nab-PXL in both tumor models suggesting that these targets are upregulated by PXL regardless of genetic makeup of tumor cells. We also confirmed the expression of these cytokines on protein level by ELISA. We found that expression of CCL20 and CXCL1 proteins is consistent with transcript expression detected by qRT-PCR. Taken together, CCL20 and CXCL1 can be the potential targets for further study, and they may have the capacity to recruit myeloid-derived lymphatic endothelial cell progenitors to the tumor site to promote lymphangiogenesis in breast cancer.
74

Zytokingenpolymorphismen bei Kindern mit akuter lymphatischer Leukämie / Genetic cytokine polymorphism in children with acute lymphoblastic leukamie

Taschik, Julia January 2016 (has links) (PDF)
Die akute lymphatische Leukämie ist die häufigste maligne Erkrankung im Kindesalter. Trotz systematischer Erhebung und Auswertung von Daten im Rahmen der ALL-BFM-Studiengruppe und der damit verbundenen kontinuierlichen Verbesserung der Prognose hat man noch immer keine Ursache für eine ALL gefunden. Daher nimmt eine umfangreiche Risikostratifizierung eine zentrale Rolle in der Behandlungsplanung einer ALL ein. Basierend auf einer exakten Stratifizierung kann die Therapie risikoadaptiert und individualisiert werden, um eine Übertherapie zu vermeiden und letztlich die Heilungschancen zu verbessern. Pro- und antiinflammatorische Zytokine kommt in den komplexen Wirkungsmechanismen des Immunsystems eine Schlüsselrolle zu. Viele Infektions-, Auto-immun- oder Tumorerkrankungen werden durch das Produktionsprofil der Zyto-kine beeinflusst. Da genetisch determinierte Zytokingenpolymorphismen Krank-heitsverläufe beeinflussen und verändern, wurde untersucht, ob Zytokine einen Einfluss auf pädiatrische Patienten mit einer ALL haben. Im Zuge dieser Arbeit wurden 95 pädiatrische Patienten mit ALL auf Polymorphismen der Zytokine TNF-α, TGF-β1, IL-10, IL-6 und IFN-γ analysiert, die im Zeitraum vom 21.06.2004 bis zum 30.04.2014 an der Kinderklinik des Universitätsklinikums Würzburg behandelt wurden. Mittels DNA-Extraktion, sequenz-spezifischer PCR und Gelelektropherese wurden 35 Proben bei Erstdiagnose und 93 zum Zeitpunkt der Remission mit folgender zentralen Fragestellung untersucht: Gibt es genetische Risikofaktoren, die Einfluss auf • die Risikogruppe • die Art der Leukämie • die Genfrequenz • die Rezidivrate und • das Gesamtüberleben einer akuten lymphatische Leukämie im Kindesalter haben und sich zudem durch Einzelnukleotidpolymorphismen in pro- und antiinflammatorischen Zytokinen auszeichnen? Im Rahmen dieser Studie konnte festgestellt werden, dass das immunsuppressive Zytokin IL-10 einen Einfluss auf die Genfrequenz, die Risikogruppe, die Rezidivrate sowie die Prognose bei Kindern mit ALL hat. Patienten mit niedrigen Zytokinexpressionsraten (Genotypen ACC/ACC und ACC/ATA) wurden häufiger in der Hochrisikogruppe therapiert, hatten mehr Rezidive und eine schlechtere Prognose als Patienten mit hohen Zytokinexpressionsraten. Dar-über hinaus ist der Genotyp GCC/ACC signifikant häufiger bei ALL-Patienten anzutreffen als im gesunden Kollektiv. Beim immunsuppressiven IL-6 konnte festgestellt werden, dass der Genotyp C/C signifikant häufiger bei Patienten mit einer ALL auftritt als bei gesunden Patienten. Ferner zeigte sich, dass es so-wohl für IL-6 als auch für TNF-α eine Änderung des Genotyps zwischen Erstdiagnose und in Remission auftrat, die Hinweise auf einen blastenspezifischen „immune-escape“-Mechanismus geben. Ebenfalls konnte gezeigt werden, dass das immunmodulatorische Zytokin TGF-β1 einen Einfluss auf die Risikogruppe sowie die Rezidivrate hat. Patienten, die eine T/T Kombination am Codon 10 aufwiesen wurden häufiger im Hochrisikozweig therapiert als Patienten mit den Genotypen T/C oder C/C. Des Weiteren wurde demonstriert, dass Patienten mit einem C/C an Codon 25 häufiger an Rezidiven erkrankten als Patienten mit ei-nem G/C oder G/G. Für die TH1 Zytokine IFN-γ sowie TNF-α wurde kein Zusammenhang zwischen der Genfrequenz, der Risikogruppe, der Art der Leukämie, der Rezidivrate oder dem Gesamtüberleben gefunden. Auch wenn man bisher noch nicht genau weiß, wie Zytokingenpolymorphismen Einfluss auf pädiatrische ALL nehmen, wird anhand dieser Arbeit gezeigt, dass Zytokine einen Beitrag zur Pathogenese der ALL leisten und daher zukünftig für eine umfassendere Risikostratifizierung geeignet sind. Darüber hinaus können diese Ergebnisse dazu beitragen, dass Zytokine als biologische Marker etabliert werden, um eine weniger toxische immunmodulierende bzw. -suppressive Therapie zu gewährleisten. Dies führt dazu, dass eine Therapie anhand des Risikoprofils individuell und prognoseverbessernd abgestimmt werden kann. Je-doch wäre für eine nachfolgende Untersuchung eine größere multizentrische Stichprobe sowie eine prospektive Evaluation der Daten erstrebenswert. Gera-de bei hereditären Erkrankungen haben einzelne Gene nur einen geringen Einfluss auf das Gesamtrisiko, sodass größere Fallzahlen erforderlich wären, um auch schwache Effekte zu detektieren. / Acute lymphoblastic leukaemia (ALL) is the most common malignant disease in childhood. Although survival rates in paediatric patients with ALL have greatly improved since effective drug combinations and risk-adapted therapy protocols were introduced, possible causes for ALL are yet to be determined. The incomplete information on the pathogenesis of ALL heightens the need for extensive risk stratification in order to develop and improve treatment methods. Exact stratification helps to continuously improve and develop risk-adapted and individual therapy approaches to minimise over- or under-treatment. Based on the empirical finding that cytokines play a decisive role in immune responses and that many autoimmune and malignant diseases are influenced by cytokine production, this study hypothesized that genetically determined cy-tokine gene polymorphisms might have an impact on children with ALL. 95 pediatric ALL patients were examined between June 2004 and April 2013 at the Children’s Hospital of the University of Würzburg with regard to cytokine gene polymorphisms in TNF-α, TGF-β1, IL-10, IL-6 and IFN-γ. Applying DNA extraction, sequence-specific PCR and gel electrophoresis, 35 samples at initial diagnosis and 93 samples in remission were obtained in order to find an answer to the following question: Are there any genetic risk factors, which influence the • risk group • type of leukaemia • gene frequency • relapse rate • overall survival with acute lymphoblastic leukaemia in childhood? Within the scope of this study the immunosuppressive IL-10 has an influence on gene frequency, risk group, relapse rate and overall survival. IL-10 high-producer-haplotypes were reduced in ALL-patients compared with healthy controls and resulted in a reduced relapse rate, a superior overall survival and resulted more often in the low risk group compared with IL-10 low producer haplotypes. By analysing immunosuppressive IL-6, it was demonstrated, that the genotype C/C is significantly more frequent in ALL-patients in comparison to healthy patients. Interestingly, with regard to IL-6 as well as to TNF-α genotypes a change in the genotype from initial diagnosis to remission was found in some patients, which may indicate a blast specific immune-escape mechanism. Moreover, the immune-modulatory cytokine TGF-β1 has an influence on risk group and relapse rate. Patients with a C/C in Codon 10 suffered more often from relapses than patients with G/C or G/G. TGF-β1 high producer haplotypes were correlated with a high initial blast-count (Codon 25 G/G) and were elevated in high-risk ALL-patients (Codon 10 T/T). For the TH1 cytokines IFN-γ and TNF-α no correlation between frequencies, risk group, type of leukaemia, re-lapse rate or overall survival could be found. Even though the mechanisms by which the cytokine polymorphisms influence the outcome of paediatric ALL remain to be determined, the data of the present study suggest an important contribution of cytokines to the pathogenesis of ALL and demonstrate their potential applicability in the clinical evaluation of prognosis in paediatric patients. Confirmatory studies correlating cytokine alleles with disease markers will support the concept of cytokine-mediated immune surveil-lance in humans as well as the importance of the genetic background of the patient for strong anti-tumour immunity and responses to therapy. These data can finally help to establish biomarkers for therapy stratification as well as immune-therapeutic tools in childhood ALL for a more risk-adapted therapy, in order to adapt the therapy intensity. However, for further studies an increase in sample size and a prospective multicentre evaluation would be desirable. Especially in hereditary diseases, single genes have only a small influence on the overall risk. That is why it is crucial to have a sufficiently high number of cases to detect even small effects.
75

Der Einfluss von Zytokingenpolymorphismen auf die Entwicklung von Osteonekrosen unter ALL-und Lymphom-Therapie bei Kindern und Jugendlichen / The influence of polymorphisms in cytokin genes on the development of osteonecrosis in children and teenagers with therapy for ALL and lymphomas

Henn, Diana January 2018 (has links) (PDF)
Jedes Jahr erkranken in Deutschland circa 1800 Kinder erstmalig an Krebs. Die akute lymphoblastische Leukämie ist dabei mit knapp einem Drittel die häufigste maligne Erkrankung im Kindesalter, Non-Hodgkin-Lymphome tragen mit 7 % und das Hodgkin-Lymphom mit 5 % bei. Die Prognose der genannten Erkrankungen bei Kindern und Jugendlichen ist sehr gut. Jedoch ist die Therapie intensiv und langwierig. Speziell bei Kindern spielen Spätschäden eine große Rolle, da diese natürlicherweise viel häufiger erlebt werden als von Erwachsenen. Eine dieser langfristigen Komplikationen ist die Entwicklung von Osteonekrosen. Da Schmerzen und Einschränkungen in der Mobilität die Folge sind, ist es wichtig, diese Komplikation besonders zu beachten. Die genaue Ursache der Entstehung von Osteonekrosen ist allerdings bislang unklar. Die vorliegende Arbeit soll durch statistische Auswertung klinischer Patientendaten und Laborparameter, sowie Analyse von Zytokingenpolymorphismen dazu beitragen, Risikofaktoren für die Entwicklung von Osteonekrosen besser abschätzen zu können. / This dissertation contributes to assess the risk of developing osteonecrosis with therapy for ALL and lymphomas. The aim was to evaluate patient data, data from the laboratory and polymorphisms in cytokin genes with the question if these data could be risk factors for developing osteonecrosis. At the end a statistical analysis was performed. The results showed that the cytokin gene polymorphism of interleukin 6 has a signifikant influence of developing osteonecrosis with therapy for ALL and lymphomas in children and teenagers
76

Development of self-adjusting cytokine neutralizer cells as a closed-loop delivery system of anti-inflammatory biologicals / Entwicklung von selbstregulierenden Zytokin-Neutralisierer-Zellen als Closed-Loop Abgabesystem von anti-inflammatorischen Biologikals

Hell, Dennis January 2019 (has links) (PDF)
The current treatment strategies for diseases are assessed on the basis of diagnosed phenotypic changes due to an accumulation of asymptomatic events in physiological processes. Since a diagnosis can only be established at advanced stages of the disease, mainly due to insufficient early detection possibilities of physiological disorders, doctors are forced to treat diseases rather than prevent them. Therefore, it is desirable to link future therapeutic interventions to the early detection of physiological changes. So-called sensor-effector systems are designed to recognise disease-specific biomarkers and coordinate the production and delivery of therapeutic factors in an autonomous and automated manner. Such approaches and their development are being researched and promoted by the discipline of synthetic biology, among others. Against this background, this paper focuses on the in vitro design of cytokine-neutralizing sensor-effector cells designed for the potential treatment of recurrent autoimmune diseases, especially rheumatoid arthritis. The precise control of inducible gene expression was successfully generated in human cells. At first, a NF-κB-dependent promoter was developed, based on HIV-1 derived DNA-binding motives. The activation of this triggerable promoter was investigated using several inducers including the physiologically important NF-κB inducers tumor necrosis factor alpha (TNFα) and interleukin 1 beta (IL-1β). The activation strength of the NF-κB-triggered promoter was doubled by integrating a non-coding RNA. The latter combined expressed RNA structures, which mimic DNA by double stranded RNAs and have been demonstrated to bind to p50 or p65 by previous publications. The sensitivity was investigated for TNFα and IL-1β. The detection limit and the EC50 values were in in the lower picomolar range. Besides the sensitivity, the reversibility and dynamic of the inducible system were characterized. Hereby a close correlation between pulse times and expression profile was shown. The optimized NF-κB-dependent promoter was then coupled to established TNFα- and IL-1-blocking biologicals to develop sensor-effector systems with anti-inflammatory activity, and thus potential use against autoimmune diseases such as rheumatoid arthritis. The biologicals were differentiated between ligand-blocking and receptor-blocking biologicals and different variants were selected: Adalimumab, etanercept and anakinra. The non-coding RNA improved again the activation strength of NF-κB-dependent expressed biologicals, indicating its universal benefit. Furthermore, it was shown that the TNFα-induced expression of NF-κB-regulated TNFα-blocking biologics led to an extracellular negative feedback loop. Interestingly, the integration of the non-coding RNA and this negative feedback loop has increased the dynamics and reversibility of the NF-κB-regulated gene expression. The controllability of drug release can also be extended by the use of inhibitors of classical NF-κB signalling such as TPCA-1. The efficacy of the expressed biologicals was detected through neutralization of the cytokines using different experiments. For future in vivo trials, first alginate encapsulations of the cells were performed. Furthermore, the activation of NF-κB-dependent promoter was demonstrated using co-cultures with human plasma samples or using synovial liquids. With this generated sensor-effector system we have developed self-adjusting cytokine neutralizer cells as a closed-loop delivery system for anit-inflammatory biologics. / Die derzeitig üblichen Behandlungsstrategien von Krankheiten werden auf Basis diagnostizierter phänotypischer Veränderungen erhoben, die auf eine Ansammlung asymptomatischer Ereignisse in physiologischen Vorgängen zurückzuführen sind. Da die Feststellung einer Diagnose bislang erst in fortgeschrittenen Krankheitsstadien, vor allem aufgrund unzureichender Früherkennungsmöglichkeiten von physiologischen Störungen, erfolgen kann, sehen sich Ärzte gezwungen, Krankheiten vornehmlich zu behandeln anstatt ihnen vorzubeugen. Daher ist es erstrebenswert, wenn zukünftige therapeutische Interventionen bereits an die Früherkennung von physiologischen Veränderungen gekoppelt werden könnten. Sogenannte Sensor-Effektor Systeme sollen krankheitsspezifische Biomarker erkennen und die Produktion und Bereitstellung von therapeutischen Faktoren in einer selbstständigen und automatisierten Art und Weise koordinieren. Solche Ansätze und deren Entwicklung werden unter anderem durch die Disziplin der synthetischen Biologie erforscht und vorangetrieben. Die vorliegende Arbeit konzentriert sich vor diesem Hintergrund auf das in vitro Design von Zytokin-neutralisierenden Sensor-Effektor Zellen, die für die potentielle Behandlung wiederkehrender Autoimmunerkrankungen, insbesondere der rheumatoiden Arthritis, konstruiert wurden. Die gezielte Ansteuerung zur induzierbaren Genexpression konnte in humanen Zellen erfolgreich generiert werden. In der vorliegenden Arbeit wurde zunächst ein NF-κB abhängiger Promoter zur induzierbaren Genexpression auf der Grundlage von HIV-1 abgleitenden DNA-Bindemotiven entwickelt. Die Aktivierbarkeit dieses Promoters wurde durch verschiedene Induktoren, insbesondere auch durch die physiologisch wichtigen NF-κB Aktivatoren Tumornekrosefaktor alpha (TNFα) und Interleukin 1 beta (IL-1β) überprüft. Die Aktivierungsstärke des NF-κB abhängigen Promoters wurde durch die Integration einer nicht-kodierenden RNA verdoppelt. Diese RNA kombiniert Strukturelemente, die im RNA-Doppelstrang DNA-Strukturen imitieren, und für die in Vorarbeiten die Bindung an p50 oder p65 nachgewiesen werden konnten. Für TNFα und IL-1β lagen das Detektionslimit und die EC50 Werte der NF-κB getriggerten Genexpression im unteren pikomolaren Bereich. Neben der Sensitivität wurde das induzierbare System bezüglich seiner Reversibilität und Dynamik charakterisiert. Dabei konnte eine enge Korrelation zwischen Pulszeiten und Expressionsmustern aufgezeigt werden. Ferner wurde der NF-κB abhängige Promoter an etablierte TNFα- und IL-1-blockierende Biologicals gekoppelt, um Sensor-Effektor Systeme mit anti-entzündlicher Aktivität zu erhalten, die potentiell zur Behandlung von Autoimmunerkrankungen, wie beispielsweise der rheumatoiden Arthritis, eingesetzt werden könnten. Bei den Biologicals wurde zwischen Ligand-blockierenden und Rezeptor-blockierenden Biologicals differenziert und unterschiedliche Varianten ausgewählt: Adalimumab, Etanercept und Anakinra. Erneut verbesserte die zusätzliche Integration der nicht-kodierenden RNA die Aktivierungsstärke der NF-κB abhängig exprimierten Biologicals, das die universelle Nutzbarkeit des hier entwickelten optimierten NF-κB-Promoters unterstreicht. Ferner wurde gezeigt, dass die TNFα-induzierte Expression von NF-κB-regulierten TNFα-blockierenden Biologika zu einem extrazellulären negativen Feedback Loop führte. Interessanterweise hat die Integration der nicht-kodierender RNA und dieser negative Feedback Loop die Dynamik und Reversibilität der NF-κB-regulierten Genexpression erhöht. Die Kontrollierbarkeit der Wirkstoffabgabe kann zudem durch den Einsatz von Inhibitoren der klassischen NF-κB-Signalisierung wie z.B. TPCA-1 erweitert werden. Die Wirksamkeit der exprimierten Biologicals wurde durch Neutralisation der Zytokine in verschiedenen Experimenten nachgewiesen. Für zukünftige in vivo Versuche konnten erste Alginat-Verkapselungen der Zellen durchgeführt werden. Die Aktivierbarkeit des NF-κB abhängigen Promoters wurde ferner durch Ko-Kultivierung mit humanen Plasmaproben und Synovialflüssigkeiten nachgewiesen. Mit diesem generierten Sensor-Effektor-System haben wir selbstregulierende Zytokin-Neutralisierer-Zellen als Closed-Loop Abgabesystem von anit-inflammatorischen Biologikals entwickelt.
77

Differential cytokine mRNA expression induced by binding of virulent and avirulent molecularly cloned equine infectious anemia viruses to equine macrophages

Lim, Wah-Seng 15 November 2004 (has links)
Equine infectious anemia virus (EIAV) causes rapid development of acute disease followed by recurring episodes of fever, thrombocytopenia and viremia, termed chronic EIA. Most infected horses control the virus by immune mechanisms and become inapparent carriers. To further our understanding of the equine immune response to EIAV, a multi-probe ribonuclease protection assay (RPA) was developed to quantitate equine-specific cytokine mRNAs. Eleven template plasmids specific to ten equine cytokine genes and the ?-actin gene were generated, from which radiolabeled anti-sense RNA probes were produced. The RPA simultaneously quantitated mRNA levels of interleukin (IL)-1, IL-1, IL-6, IL-8, IL-10, IL-12 p35, IL-12 p40, interferon (IFN)-, transforming growth factor (TGF)-1 and tumor necrosis factor (TNF)- in equine peripheral blood mononuclear cells and equine monocyte-derived macrophages (EMDM). The assay detected as few as 5105 RNA molecules and displayed coefficients of variation of 0.03-0.08 when normalized to -actin expression. Using this RPA, cytokine expression in EMDM infected with 2 molecularly cloned viruses (EIAV17 and EIAV19) was determined. EIAV17 varies from EIAV19 only in env, rev and LTR and causes fatal disease in Shetland ponies. When added to EMDM cultures, virulent EIAV17 stimulated expression of IL-1, IL-1, IL-6, IL-10 and TNF-. These cytokine mRNAs were significantly elevated by 0.5 to 1 hr post infection (hpi) and returned to basal levels by 12 to 24 hpi, indicating modulation by early event(s), such as receptor binding. In contrast to EIAV17, EIAV19 is avirulent in vivo and failed to induce any of the tested cytokines in EMDM. These data show a direct correlation between the virulence of the EIAV clone and the induction of cytokines. The cytokines stimulated by EIAV17 may contribute to EIA-associated symptoms, enhance viral replication in the host, and regulate the host immune response. To determine whether cytokine induction requires EIAV17 replication, EMDM cultures were exposed to UV-inactivated EIAV17 and cytokine induction was monitored. UV-inactivation did not block cytokine induction by EIAV17, suggesting dispensability of viral replication. Given that EIAV17 induces cytokines in a rapid and replication-independent manner, the activation of cytokine expression is likely mediated by binding of EIAV17 to equine macrophage receptor(s).
78

Cannabinoids as neuroprotective agents : a mechanistic study

Nilsson, Olov January 2006 (has links)
Glucose and oxygen supply to the brain is critical for its proper function and when it is restricted as during a stroke, neurons and glial cells quickly become necrotic leading to structural damage as well as functional impairment and even death. To date there are few effective therapies that inhibit the neurodegenerative process and improves the outcome for the affected individual. One possible target is the cannabinoid system. Cannabinoid receptor agonists reduce ischemic volume, endogenous cannabinoid levels are elevated during neurodegenerative insults and mice devoid of the central cannabinoid receptor are more seriously affected by experimental stroke than wild type mice. The cannabinoids are also ascribed anti-inflammatory properties and post ischemic inflammation has been proposed to contribute to the evolution of the ischemic damage. In this thesis mechanisms that can contribute to cannabinoid neuroprotection have been studied. In papers I and II the chick was used as a model species, since preparation of embryonic primary neuronal cultures from chick is relatively simple and time efficient compared to rodent primary cultures. Both adult and embryonic chick brain membranes contain functional CB1 receptors and in the cultures they are coupled to inhibition of cAMP production. In embryonic primary cultures, neurons were not protected from glutamate toxicity by preincubation with CB receptor agonists suggesting that postsynaptic cannabinoid mediated neuroprotection is not effective in this system. The effect of cannabinoid agonists on neutrophil chemotaxis and transmigration was investigated in paper III. The CB1/CB2 agonist WIN 55,212-2 inhibited TNF-α-induced transmigration across ECV304 cell monolayers. The effect of WIN 55,212-2 on this process which was mediated by a reduction of IL-8 release from the ECV304 cells rather than a direct effect upon the migratory response to IL-8 was not possible to abolish with CB1 or CB2 agonists suggesting a mechanism distinct from the cannabinoid receptors is operative. In paper IV the photothrombotic ring stroke model was evaluated to determine if it is suitable in intervention studies targeting the cannabinoid system. Three major endpoints were of interest, ischemic volume, neutrophil infiltration and CB1 receptor function. Consistent with previous studies the ischemic volume peaked at 48 hours after irradiation. Neutrophil infiltration was quantified using a myeloperoxidase activity assay. The assay revealed an increase in myeloperoxidase activity 48 hours after irradiation, albeit at a modest level. The function of the CB1 receptor was assessed by radioligand binding and there was no change in either total binding or functional G-protein coupling following photothrombosis. Taken together these results indicate that it is feasible to undertake cannabinoid intervention studies in this model.
79

Patterns of Cytokine Response in Patients Undergoing Curative Radiotherapy for Prostate Cancer

Christensen, Eva 24 February 2009 (has links)
Ionizing radiation induces specific proteins involved in DNA repair, cell death, inflammation and tissue injury. The radiation response of proteins within a uniform prostate cancer (PCa) radiotherapy (RT) population has been studied to a limited extent. In this thesis, the proteomic responses of patients undergoing curative RT for intermediate-risk PCa were determined for a panel of pro-inflammatory cytokines from pre-RT baseline to last treatment (39 vs. 33 fractions depending on whether the cohort received primary or post-prostatectomy RT respectively). Longitudinal proteomic research is feasible at our institution based on the study design presented herein. Interferon (IFN)-g and interleukin (IL)-6 were significantly increased during RT and these changes followed consistent patterns modeled by linear and quadratic functions respectively. Furthermore, acute gastrointestinal (GI) and genitourinary (GU) toxicities were significantly associated with IL-2 and IL-1 levels respectively during RT. Taken together this research supports cytokines as potential biomarkers of normal tissue radiation response.
80

Patterns of Cytokine Response in Patients Undergoing Curative Radiotherapy for Prostate Cancer

Christensen, Eva 24 February 2009 (has links)
Ionizing radiation induces specific proteins involved in DNA repair, cell death, inflammation and tissue injury. The radiation response of proteins within a uniform prostate cancer (PCa) radiotherapy (RT) population has been studied to a limited extent. In this thesis, the proteomic responses of patients undergoing curative RT for intermediate-risk PCa were determined for a panel of pro-inflammatory cytokines from pre-RT baseline to last treatment (39 vs. 33 fractions depending on whether the cohort received primary or post-prostatectomy RT respectively). Longitudinal proteomic research is feasible at our institution based on the study design presented herein. Interferon (IFN)-g and interleukin (IL)-6 were significantly increased during RT and these changes followed consistent patterns modeled by linear and quadratic functions respectively. Furthermore, acute gastrointestinal (GI) and genitourinary (GU) toxicities were significantly associated with IL-2 and IL-1 levels respectively during RT. Taken together this research supports cytokines as potential biomarkers of normal tissue radiation response.

Page generated in 0.0192 seconds