• Refine Query
  • Source
  • Publication year
  • to
  • Language
  • 15
  • 4
  • 4
  • 2
  • 1
  • Tagged with
  • 32
  • 11
  • 9
  • 6
  • 6
  • 6
  • 5
  • 5
  • 5
  • 5
  • 5
  • 5
  • 5
  • 4
  • 4
  • 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.
11

Tracking the Humoral Immune Response In Type 1 Diabetes

January 2015 (has links)
abstract: Type 1 diabetes (T1D) is a chronic autoimmune disease characterized by progressive autoimmune destruction of insulin-producing pancreatic β-cells. Genetic, immunological and environmental factors contribute to T1D development. The focus of this dissertation is to track the humoral immune response in T1D by profiling autoantibodies (AAbs) and anti-viral antibodies using an innovative protein array platform called Nucleic Acid Programmable Protein Array (NAPPA). AAbs provide value in identifying individuals at risk, stratifying patients with different clinical courses, improving our understanding of autoimmune destructions, identifying antigens for cellular immune response and providing candidates for prevention trials in T1D. A two-stage serological AAb screening against 6,000 human proteins was performed. A dual specificity tyrosine-phosphorylation-regulated kinase 2 (DYRK2) was validated with 36% sensitivity at 98% specificity by an orthogonal immunoassay. This is the first systematic screening for novel AAbs against large number of human proteins by protein arrays in T1D. A more comprehensive search for novel AAbs was performed using a knowledge-based approach by ELISA and a screening-based approach against 10,000 human proteins by NAPPA. Six AAbs were identified and validated with sensitivities ranged from 16% to 27% at 95% specificity. These two studies enriched the T1D “autoantigenome” and provided insights into T1D pathophysiology in an unprecedented breadth and width. The rapid rise of T1D incidence suggests the potential involvement of environmental factors including viral infections. Sero-reactivity to 646 viral antigens was assessed in new-onset T1D patients. Antibody positive rate of EBV was significantly higher in cases than controls that suggested a potential role of EBV in T1D development. A high density-NAPPA platform was demonstrated with high reproducibility and sensitivity in profiling anti-viral antibodies. This dissertation shows the power of a protein-array based immunoproteomics approach to characterize humoral immunoprofile against human and viral proteomes. The identification of novel T1D-specific AAbs and T1D-associated viruses will help to connect the nodes in T1D etiology and provide better understanding of T1D pathophysiology. / Dissertation/Thesis / Doctoral Dissertation Biological Design 2015
12

Anti-fumarase Antibody Promotes the Dropout of Photoreceptor Inner and Outer Segments in Diabetic Macular Oedema / 抗フマラーゼ抗体は糖尿病黄斑浮腫における視細胞内節および外節の脱落を促進する

Yoshitake, Shin 23 May 2019 (has links)
京都大学 / 0048 / 新制・課程博士 / 博士(医学) / 甲第21954号 / 医博第4496号 / 新制||医||1037(附属図書館) / 京都大学大学院医学研究科医学専攻 / (主査)教授 渡邉 大, 教授 伊佐 正, 教授 椛島 健治 / 学位規則第4条第1項該当 / Doctor of Medical Science / Kyoto University / DFAM
13

Anti-Hexokinase 1 Antibody as a Novel Serum Biomarker of a Subgroup of Diabetic Macular Edema / 糖尿病黄斑浮腫の一部症例における新規血清バイオマーカーとしての抗ヘキソキナーゼ1抗体

Yoshitake, Tatsuya 23 March 2020 (has links)
京都大学 / 0048 / 新制・課程博士 / 博士(医学) / 甲第22320号 / 医博第4561号 / 新制||医||1041(附属図書館) / 京都大学大学院医学研究科医学専攻 / (主査)教授 椛島 健治, 教授 大森 孝一, 教授 森田 智視 / 学位規則第4条第1項該当 / Doctor of Medical Science / Kyoto University / DFAM
14

OPTIMERING AV EN INDIREKT ELISA FÖR DETEKTION AV AUTOANTIKROPPAR VID JUVENIL IDIOPATISK ARTRIT / OPTIMIZATION OF AN INDIRECT ELISA FOR THE DETECTION OF AUTOANTIBODIES IN JUVENILE IDIOPATHIC ARTHRITIS

Friberg, Viktor January 2023 (has links)
Juvenil idiopatisk artrit (JIA) är en autoimmun reumatisk sjukdom som drabbar barn före 16 års ålder. Den vanligaste varianten är oligoartikulär JIA, vilket innebär att den påverkar två till fyra leder med symptom så som svullnad, ömhet, stelhet, rodnad eller nedsatt motorik. Oligoartikulär JIA är även associerad med uveit, vilket är en autoimmun ögonsjukdom som förstör synen. Sjukdomen är i nuläget dåligt förstådd och forskning behövs för att kunna identifiera markörer som kan användas för diagnostik. Enzymkopplad immunadsorberande analys (ELISA) är inom vårdens laborativa arbete en mycket vanlig metod för att undersöka patienters serum och identifiera specifika markörer som tyder på sjukdom. En ELISA kan utföras på olika sätt beroende på om den letar efter antigen eller antikroppar. Syftet med denna studie var att optimera en indirekt ELISA för detektion av autoantikroppar och genomföra en metodjämförelse med en redan väl undersökt kulbaserad autoantikroppsmetod. Studien omfattar 14 serumprov från olika patienter och använder sig av rekombinant framställda protein epitope signature tag (PrEST)-antigener för att identifiera autoantikroppar. PrEST-antigener består av ett humant variabelt proteinsegment och en protein-tag som består av ett albuminbindande protein (ABP) med en N-terminal HIS-tag (His6ABP). För att förhindra ospecifik inbindning till His6ABP-delen av PrEST-antigenerna så framställdes His6ABP, med vilket serum inkuberades innan de undersöktes med ELISA. Då resultatet tolkades binärt kunde stor likhet ses mellan de två olika metoderna för samtliga PrEST-antigener som undersöktes, vilket innebär att metoden kan fortsätta utforskas. Resultatet visade också att His6ABP-delen skulle kunna orsaka korsreaktivitet, vilket dock inte är något negativt för metodens validitet. / Juvenile idiopathic arthritis (JIA) is an autoimmune rheumatic disease that affects children before the age of 16. The most common variant is oligoarticular JIA, which means it affects two to four joints with symptoms such as swelling, tenderness, stiffness, redness, or reduced mobility. Oligoarticular JIA is also associated with uveitis, an autoimmune eye disease which damage eyesight. The disease is currently poorly understood, and research is needed to identify markers that can be used for diagnostics. Enzyme-linked immunosorbent assay (ELISA) is a very common method in healthcare laboratory work to examine patients' serum and identify specific markers that indicate disease. An ELISA method can be performed in different ways depending on whether it is looking for antigen or antibodies. The aim of this study was to optimize an indirect ELISA for detection of autoantibodies and conduct a method comparison with an already well established bead-based autoantibody array method. The study included 14 sera samples from different patients and used recombinantly produced protein epitope signature tag (PrEST) antigens to identify autoantibodies. PrEST antigens consist of a human variable protein segment and a protein tag consisting of albumin binding protein (ABP) with an N-terminal HIS-tag (His6ABP). To prevent non-specific binding to the His6ABP portion of the PrEST antigens, His6ABP were recombinantly produced and used for pre-absorption of serum before being examined by ELISA. When the result was interpreted binary, great similarity could be seen between the two different methods for all PrEST antigens examined, which calls for further exploring of the method. The result also showed that the His6ABP part could possibly cause cross-reactivity, which is interesting but doesn’t affect the validity of the method.
15

Glycine receptor antibodies : pathogenic mechanisms and clinical correlates

Carvajal González, Alexander January 2014 (has links)
Glycine receptor antibodies have been identified in a few patients with progressive encephalomyelitis with rigidity and myoclonus (PERM), a highly disabling disorder characterised by rigidity, spasm and brainstem symptomatology. The clinical characteristics of patients with glycine receptor antibodies have not yet been fully described and it is not clear whether GlyR-Abs are pathogenic or just an epiphenomenon. This study examined the clinical features and immunotherapy responses of 45 patients; characterised the GlyR-Ab pathogenicity, subunit specificity and binding to different brain region in vitro, and examined mice injected with GlyR-Abs to model the disease in vivo. Most of the patients were classified as PERM but some patients had symptomatology beyond the classical motor manifestations and there were four patients with tumours (thymomas and lymphomas). GlyR-Ab titres were varied in serum and CSF, but there was intrathecal synthesis in the six patients with suitable samples. Most patients were very disabled but almost all showed excellent responses to immunotherapies. The antibodies were mainly IgG1 and IgG3 subclasses, activated complement on glycine receptor-transfected HEK cells at room temperature, and caused internalisation and lysosomal degradation of the glycine receptors at 37°C. GlyR-Abs bound to rodent spinal cord and brainstem co-localising with monoclonal antibodies to GlyRα1 on the surface of neurons. GlyR-IgG injected intra-peritoneally led to impairment in forced walking ability, sensorimotor function and coordination. Analysis of the brain showed that animals injected with patients' IgG, but not control IgG, had antibodies bound to the brainstem, spinal cord, cerebellum and caudate, co-localising with GlyRα1 monoclonal antibody. Intra-cerebroventricular injection of GlyR-IgG caused an anxiety-like behaviour in mice but no evident motor disturbances. These results provide the first evidence of in vitro and in vivo pathogenicity of the GlyR-Abs, supporting the use of long term immunosuppression in these patients to provide them with a good prognosis.
16

Profiling the autoantibody repertoire in systemic sclerosis

Pohjanen, Emmie January 2021 (has links)
Systemisk skleros (SSc) är en autoimmun rheumatisk sjukdom som kännetecknas av fibros i huden och/eller de interna organen, vaskulopati och en autoimmun reaktion från immunförsvaret, med eller utan specifika autoantikroppsprofiler. Diagnostisering och sjukdomsbehandling försvåras av sjukdomens heterogena natur. Det finns därför ett behov av pålitliga autoantikroppsbiomarkörer som kan bistå vid diagnostisering av patienter. Autoantikroppar som förekommer i serum kan avslöja sjukdomstillståndet hos patienter samt indikera en prognos om de korreleras till ett specifikt klinisk symtom. Syftet med denna studie var att identifiera autoantikroppar som kanditater till nya biomarkörer inom systemisk skleros i hopp om att dessa ska kunna förbättra stratifiering av patienter, samt att addera kunskap om autoantikroppsreaktivitet inom sjukdomen. Autoantikroppsprofilerna i 107 serumprover, där 55 tillhörde SSc-patienter och 52 tillhörde inflammatoriska kontroller, analyserades i två faser med en planar antigen array för en initial objektiv identifiering av möjliga autoantikroppskandidater, som sedan verifierades i en suspension bead array. Resultaten konfirmerar reaktivitet mot kända autoantigen, så som centromer protein B (CENPB) och DNA topoisomeras I (TOP1), samt identifierar fosfatidylinositol-5-fosfat 4-kinas typ 2 beta (PIP4K2B) som en ny, potentiellt specifik, autoantikroppskandidat för sjukdomen. Tripartite motif containing 21 (TRIM21) som är ett känt autoantigen hos flera systemiska autoimmuna sjukdomar visar potential för att kunna stratifiera sjukdomen. Resultaten i denna studie adderar ny information till kontexten inom autoantikroppsreaktivitet hos patienter med systemisk skleros som efter en mer omfattande dataanalys förhoppningsvis kommer att vara användbar inom diagnostisering av patienter samt för att skräddarsy behandling av sjukdomen. / Systemic sclerosis (SSc) is a highly heterogeneous rheumatic autoimmune disease that is characterized by fibrosis of the skin and/or visceral organs, vasculopathy, and an irregular immune response with or without specific autoantibody profiles. The heterogenic nature of the disease creates a challenge in diagnosis and clinical management of patients. There is thus a need for reliable autoantibody biomarkers that could aid in patient stratification. Serum autoantibodies are indicative of the disease state and may reveal prognosis if correlated to a specific clinical feature. This study aimed to discover novel autoantibody biomarker candidates with the hopes of improving patient stratification and to provide additional knowledge on the autoantibody reactivity in systemic sclerosis. By using a two-phase study design, an autoantibody profiling of 107 serum samples, consisting of 55 SSc samples and 52 inflammatory controls, was performed using the planar antigen array for initial discovery and a suspension bead array for verification. Resulting data confirms reactivity to known targets such as centromere protein B (CENPB) and DNA topoisomerase I (TOP1), while also identifying phosphatidylinositol-5-phosphate 4-kinase type 2 beta (PIP4K2B) as a potential novel target that is specific to the disease. Tripartite motif containing 21 (TRIM21), a known target among several systemic autoimmune diseases, show potential as a target for patient stratification. The results of this study add new information to the context of autoantibody reactivity in systemic sclerosis, which after more extensive data analysis, could be useful in improving the stratification of patients and in tailoring treatment.
17

PROTEIN EXPRESSION AND CHARACTERIZATION OF THE MAJOR AUTOANTIGEN (TITIN DOMAIN) ASSOCIATED WITH AUTOIMMUNERIPPLING MUSCLE DISEASE

Zelinka, Lisa M. 20 April 2015 (has links)
No description available.
18

THE DEVELOPMENT AND OPTIMIZATION OF A HUMAN MEGAKARYOCYTE CULTURE FROM HEMATOPOIETIC PROGENITOR CELLS ISOLATED FROM NORMAL PERIPHERAL BLOOD FOR IN VITRO INVESTIGATION OF PLATELET DISORDERS

Jafari, Reza 25 September 2014 (has links)
<p>Megakaryocyte cultures are a strong tool for the in vitro investigation of platelet production in platelet disorders. Peripheral blood derived hematopoietic progenitor cells (PB-HPCs) are the most accessible source of HPCs with high potential to produce mature megakaryocytes in vitro; however, they are present in low numbers making peripheral blood an inefficient source. Additionally, a megakaryocyte culture with an optimized thrombopoietin (TPO) concentration is required which can reliably allow the investigation of suppressive effects of antibodies/plasma from immune thrombocytopenia (ITP) patients. In this study, we developed a megakaryocyte culture with the utilization of human PB-HPCs in an efficient fashion resulting in the production of high purity megakaryocytes in a TPO-dependent manner.</p> <p>The mononuclear fraction was collected from 180 mL of peripheral whole blood and CD34+ cells were isolated by a positive selection yielding the average of 5.5 x 105 ± 2.5 x 105 CD34+ cells (n = 18). Using 96-well tissue-culture plates and seeding 10,000 CD34+ cells/well, the average of 13 experiments in triplicate can be set up utilizing isolated CD34+ in an efficient manner. Capitalizing on a TPO dose-dependent megakaryocyte production experiment, 20 ng/mL was established as the TPO concentration which resulted in the production of mature megakaryocytes without reaching the plateau in megakaryopoiesis response. On day 11 of culture, the expression of megakaryocytic lineage (CD41/61+) and maturation (CD41/61+CD42+) markers peaked at 90.65% and 76.10%. In conclusion, this culture system has broad application for investigation of platelet disorders and drug discovery which can be accessible to all researchers.</p> / Master of Science (MSc)
19

Adhäsionsmoleküle auf zirkulierenden humanen Monozyten bei essentieller Hypertonie

Lau, Susan Katrin 10 December 2004 (has links)
HINTERGRUND: Das Ziel dieser Studie bestand darin, die mögliche Rolle von zirkulierenden humanen Monozyten in der Pathologie der essentiellen Hypertonie zu untersuchen. Wir verglichen die Expressionsmuster unterschiedlicher Adhäsionsmoleküle auf isolierten Monozyten des peripheren Blutes von Normalkontrollen und Hypertonikern. Wir bestimmten die Veränderungen durch Stimulation mit Lipopolysaccharide (LPS), Angiotensin II (AT) und agonistische Angiotensin Rezeptor Typ I-Autoantikörper (AT1-AK) sowie den Einfuß des AT1-Rezeptor-Antagonist Losartan und des auch an MAC-1 bindenden Glykoprotein IIb/IIIa Rezeptor-Antikörper Abciximab. METHODIK: Blutproben von 18 Patienten mit essentieller Hypertonie und 20 gesunden Normalkontrollen wurden verglichen. Die Monozyten wurden mittels Dynabead-Negativ-Isolierung gewonnen. Die Adhäsionsmolekül-Expression wurden nach Färbung mit fluoreszenzgekoppelten Antikörpern gegen CD11a, CD11b, CD29, CD31, CD44, CD49d, CD54 und CD62L mittels FACS Messung bestimmt. ERGEBNISSE: Auf Monozyten hypertensiver Patienten ist die Expression von CD11a, CD11b und CD54 signifikant erhöht. Mit Inkubation erhöht sich die Expression von CD54 und CD44, während CD11b, CD31 und CD49d erniedrigt werden und CD11a konstant bleibt. LPS-Stimulation führt zu einer signifikanten Erhöhung der CD11b und CD54 Expression. Ausdruck der Aktivierung durch AT-Stimulation ist eine erhöhte CD11b Expression. AT1-AK erhöhen die Expression von CD11b, CD54 und CD49d signifikant. Losartan verringert nur tendenziell und teilweise die AT und AT1-AK bedingten Expressionsveränderungen. Der LPS bedingte Anstieg der CD11b Expression auf Monozyten wird durch Abciximab vermindert. SCHLUSSFOLGERUNG: Wir demonstrieren die Bedeutung voraktivierten Monozyten bei Hypertonie in der Pathogenese der Arteriosklerose. / BACKGROUND: The purpose of this study was to investigate the possible involvement of human peripheral blood monocytes in the pathology of hypertensive disease. We determined the in vitro expression patterns of adhesion molecules on isolated peripheral blood monocytes from normal controls and from hypertensive patients. We investigated and compared the ability of lipopolysaccharide (LPS), angiotensin II (Ang II) and Agonistic AT1 receptor autoantibodies (AT1-AA) to stimulate monocytes and the influence of preincubation with an Ang II type 1 receptor antagonist (losartan) or Glykoprotein IIb/IIIa rezeptor-antibody Abciximab. METHODS: Blood samples were obtained from 18 patients with essential hypertension and from 20 normotensive healthy individuals used as a control group. Peripheral blood monocytes were isolated by negative Dyna Bead Isolation. Adhesion molecules were measured using immunofluorescence of monocytes labelled with antibody against CD11a and b, CD29, CD31, CD44, CD49d, CD54 and CD62L by flow cytometry. RESULTS: The expression of CD11a, CD11b and CD54 was significantly higher in hypertensive patients versus healthy individuals directly after isolation. With incubation the expression of CD44 and CD54 was increased and the expression of CD 11b, CD31 and CD49d was decreased, whereas CD11a shows a constant expression. Monocytes showed increased expression of CD11b and CD54 after LPS stimulation. CD11b expression was significantly increased after stimulation with Ang II, after stimulation with AT1-AA Monocytes showed an increased expression of CD11b, CD54 and CD49. Losartan was partially but not significantly effective in blocking the effects of Ang II or AT1-AA stimulation. Incubation with Abciximab was reducing the LPS induced CD11b Epression. CONCLUSIONS: These data indicate that preactivated monocytes from hypertensives may be of pathogenic importance in atherosclerosis.
20

Charakterisierung von Autoantikörpern gegen Protease-aktivierte Rezeptoren 1 und 2 und gegen Endothelin-Rezeptor ET(A)

Freier, Jeannette 09 January 2008 (has links)
Einige Patienten mit Raynaud-Syndrom, Urtikaria, koronarer Herzkrankheit, Angina pectoris, oder Pulmonaler Hypertonie haben funktionelle Autoantikörper gegen die Thrombin-Rezeptoren PAR1/2 und/oder gegen den Endothelin-Rezeptor ET(A). In dieser Arbeit wurde die Wirkung solcher Patienten-IgG-Präparate auf Funktionen von Ventrikel-Kardiomyozyten neonataler Ratten; humanen, glatten Muskelzellen aus Coronararterien (hCASMC), frisch isolierten, humanen Thrombozyten sowie von Monozyten untersucht. Zum Vergleich wurden die PAR-Agonisten Thrombin und das stimulierende Peptid SFLLRN sowie Endothelin-1 verwendet. Während aufgereinigte ET(A)-Autoantikörper ERK1/2 in Kardiomyozyten nicht aktivierten, bewirkten IgG-Präparate mit PAR-Autoantikörpern hier eine ähnliche Aktivierung wie das Peptid SFLLRN. Überraschenderweise bewirkte Kontroll-IgG eine starke Aktivierung von ERK1/2. Die Coinkubation der Kardiomyozyten mit Antikörper-Präparaten und IL-1beta erhöhte die Phosphorylierung von ERK1/2 in allen Fällen. In hCASMCs bewirkten IgG-Präparate mit PAR-Autoantikörpern und Kontroll-IgGs eine Aktivierung von ERK1/2, ET(A)-Autoantikörper nicht. Die Ergebnisse der Thrombozytenaktivierung durch Patienten-IgG waren unterschiedlich. Versuche mit vorstimulierten Thrombozyten zeigten, dass ein stimulierender Einfluss der Autoantikörper auf präaktivierte Thrombozyten nicht ausgeschlossen werden kann. Ohne Vorstimulation jedoch schien Patienten-IgG eher einen hemmenden Einfluss auf die Thrombozytenfunktion zu haben. Eine Vorinkubation von Monozyten mit Patienten-IgG hatte keinen Einfluss auf die PMA-induzierte Produktion von Superoxidanion im Vergleich zu Kontroll-IgG. Nur bei zwei von fünf Patienten-IgGs konnte eine stimulierende Wirkung anhand der monozytären ERK1/2-Phosphorylierung gefunden werden. Die Schlussfolgerung aus dieser Arbeit liegt darin, dass PAR1/2- und ET(A)-Autoantikörper keine allgemeine Wirkung auf die Funktion von glatten Gefäßmuskelzellen, Thrombozyten und Monozyten zeigten. Die Unterscheidung von Autoantikörper-positiven und -negativen IgG-Präparaten war nur über die Bestimmung der Pulsationsrate von Kardiomyozyten möglich. / Some patients with Raynaud’s syndrome, urticaria, coronary artery disease, Angina or pulmonary hypertension have functional autoantibodies against thrombin receptors PAR1/2 and/or against endothelin receptor ET(A). In this work the effects of such patients’ IgG preparations on functions of ventricular cardiomyocytes of neonatal rats, human smooth muscle cells from coronary arteries (hCASMC); freshly isolated, human platelets as well as monocytes were investigated. For comparison, the PAR agonists thrombin and the stimulating peptide SFLLRN as well as endothelin-1 were used. While purified autoantibodies against ET(A) did not activate ERK1/2 in cardiomyocytes, IgG preparations with autoantibodies against PAR1/2 resulted in a similar activation as the peptide SFLLRN. Surprisingly, control IgG also caused a strong activation of ERK1/2. Coincubation of cardiomyocytes with antibody preparations and IL-1beta increased the phosphorylation of ERK1/2 in all cases. In hCASMCs, IgG preparations with PAR-autoantibodies and control IgGs caused activation of ERK1/2, whereas ET(A)-autoantibodies did not. The results of platelet activation with patients’ IgG were varying. Tests with prestimulated platelets showed, that a stimulating effect of the autoantibodies on preactivated platelets can not be excluded. However, without prestimulation patients’ IgG rather seemed to have an inhibiting effect on platelet function. Preincubation of monocytes with patients’ IgG had no influence on PMA-induced production of superoxide anion compared with control IgG. Only two of five patients’ IgGs showed a stimulating effect on monocytic ERK1/2 phosphorylation. In conclusion, PAR1/2- and ET(A)-autoantibodies showed no common effects on the function of vascular smooth muscle cells, platelets and monocytes. The differentiation of autoantibody-positive and -negative preparations of IgG only was possible by determining the beating rate of cardiomyocytes.

Page generated in 0.0391 seconds