Global ETD Search

41	Untersuchung Rezeptor-vermittelter Interaktionen zwischen Defensinen und Zellen des Immunsystems / Investigations of receptor-mediated interactions between defensins and cells of the immune system Grigat, Jasmin 07 November 2007 (has links) No description available. 570 Biowissenschaften, Biologie WHC 700 Zellrezeptoren Mathematics and Natural Science Chemotaxis Defensine Rezeptoren Makrophagen Mastzellen Lymphocyten dendritische Zellen chemoattraction defensins receptors macrophages mast cells Lymphocytes dendritic cells 42.15 Zellbiologie
42	Study of the modulation of innate immune responses in intestinal epithelial cells by Toxoplasma gondii and its correlation with parasite virulence / Etude de la modulation des réponses immunitaires innées dans les cellules épithéliales intestinales par Toxoplasma gondii, et sa corrélation avec la virulence du parasite Morampudi, Vijay 28 October 2010 (has links) Early innate response of intestinal epithelial cells is the first line defense against enteric pathogens. Toxoplasma gondii infections acquired naturally via the peroral route, encounter intestinal epithelial cells early post-infection. Although the population structure of T. gondii is known to be highly clonal, clinical strains of T. gondii have been classified into three genotypes based on their virulence. In this study we investigated whether human intestinal epithelial cell immune response to T. gondii is virulence dependent. We demonstrated distinct virulence of the three T. gondii genotype strains evaluated in human intestinal epithelial cells by their capacity to replicate and induce host cell cytotoxicity. The early host innate mechanisms such as activation of signaling pathways and induction of innate effectors were likewise differentially elicited by the three T. gondii strains. Low levels of TLR dependent NF-kB activation and a failure to rapidly up-regulate innate cytokine and chemokine genes was observed after virulent Type I strain infection. In contrast, early innate response to the less virulent Type II strain was rapid, efficient and led to high levels of IL-8 and IL-6 secretion, whereas response to Type III parasites was intermediate. Early expression of b-defensin 2 gene was suppressed specifically by virulent Type I strain and its activation prior to infection in intestinal epithelial cells led to decreased parasite viability. These findings provide evidence for T. gondii strain virulence dependent down-modulation of early human intestinal epithelial cell innate responses and highlight the importance of these cells in host defense against this infection. / Doctorat en Sciences biomédicales et pharmaceutiques / info:eu-repo/semantics/nonPublished Disciplines biomédicales diverses Toxoplasma Immune response Intestines -- Diseases Toxoplasma Réaction immunitaire Intestins -- Maladies virulent and avirulent strains innate immune genes Toll-like receptors NF-kB defensins Intestinal epithelial cells
43	Nové mechanismy T buněčně zprostředkované střevní autoimunity proti Panetovým buňkám / Novel mechanisms of T cell-mediated intestinal autoimmunity to Paneth cells Brabec, Tomáš January 2017 (has links) (En) Paneth cells are one of the major player in the maintenance of the homeostatic relationship between intestinal microbiota and the immune system. This function is largely achieved by their production of bactericidal enteric α-defensins (ED) and other antimicrobials. Disruption of Paneth cell functions is associated with severe human disorders such as Crohn's disease (CD) and Autoimmune Polyendocrinopathy- Candidiasis-Ectodermal Dystrophy (APECED). However, there is only a very limited information regarding the interactions and regulatory circuits operating between Paneth cells and intestinal immune system in either health or under pathological conditions. The previous study conducted in our laboratory described a new mechanism for the initiation and maintenance of Paneth cells targeted autoimmunity. The suggested model was that ED-specific T cells escape the selection in the thymus, infiltrate the intestine and diminish Paneth cell numbers through autoimmune destruction. This process also lead to the accumulation of inflammation- inducing bacteria, which were implied to exacerbate the inflammatory autoimmunity. Since this model of intestinal autoimmunity is of correlative nature, its intrinsic mechanism and functional relationships between immune system, Paneth cells and microbiota are largely...
44	Duplicacions segmentàries a la regió cromosòmica humana 8P23.1: evolució i expansió d'una nova família gènica Bosch Pages, Nina 19 December 2008 (has links) Les duplicacions segmentàries (DSs), o també anomenades duplicons o Low copy Repeats (LCRs), són regions de coma mínim 1 kb amb un alt nivell d'identitat (>90%), que estan presents almenys dues vegades en el genoma. La regió 8p23.1 consta de 6.5 Mb a la part distal del braç curt del cromosoma 8 i està flanquejada per duplicacions segmentàries. Degut a la seva arquitectura genòmica aquesta regió és susceptible a patir reordenaments mediats per recombinació homòloga no al·lèlica entre les DSs, com per exemple la inversió polimòrfica de 8p23.1 [inv(8)(p23)], present en un de cada quatre individus de la població general europea i japonesa, així com d'altres reorganitzacions menys corrents.El treball realitzat en aquesta tesi doctoral pretén aprofundir en la caracterització de la complexa arquitectura genòmica d'aquesta regió. En la nostra primera aproximació a l'estudi de les DSs que flanquegen la regió cromosòmica 8p23.1, es va identificar una nova família gènica específica de primats, la família gènica FAM90A.Així, bona part d'aquesta tesi doctoral està centrada en l'anàlisi de l'origen, formació, evolució i expansió de FAM90A en els homínids. Per altra banda també s'ha analitzant en detall la variabilitat de FAM90A com a variant en número de còpia (CNV) en diferents poblacions humanes.Finalment, s'ha establert la freqüència de la inversió que afecta a 8p23.1 en població espanyola. També s'ha procedit a genotipar diversos individus homozigots per la inversió i s'ha predit l' estatus de la inversió en 150 individus del projecte HapMap i s'ha analitzat l'efecte que té aquesta reorganització sobre els nivells d'expressió dels gens de la regió. / Segmental duplications (SDs), also known as duplicons or Low Copy Repeats (LCRs), are regions of a minimum of 1 kb with a high sequence identity level (>90%), which are present at least two times in the genome. The 8p23.1 region extends 6.5 Mb at the distal part of the short arm of chromosome 8 and it is flanked by segmental duplications. Due to its genomic architecture the region is prone to suffer rearrangements mediated by non-allelic homologous recombination between these SDs, such as the polymorphic inversion of 8p23.1 [inv(8)(p23)], which is present in one out of every four of European and Japanese general population individuals, as well as other less frequent rearrangements.The aim of the work presented in this doctoral thesis is to get insights in the characterization of the genomic architecture of this complex region. Our first approach to study the SDs flanking 8p23.1 region resulted in the identification of a novel gene family which is primate specific, the FAM90A gene family. Thus, this doctoral thesis is mainly focused on the analysis of the origins, formation, evolution and expansion of FAM90A in hominoids. It has also been analyzed in detail the variability of FAM90A as a copy number variant (CNV) in different human populations.Finally, it has been established the frequency of the inversion affecting 8p23.1 region in the Spanish population. Several homozygous inverted individuals have been genotyped and the status for the inversion has been predicted for 150 HapMap individuals, as well as the effect of this rearrangement on the gene expression levels of the genes contained in the region. NAHR Chromosomal rearrangements 8p23.1 Defensins Correlation Gene fusion Gene expansion Mosaicism Inversions Primates Structural variant Copy number variant or CNV Gene family FAM90A Segmental duplicactions Illumina SNPassoc WGS Real time- PCR FISH Ka/Ks Polimorfisme Trastorn genòmic NAHR Reordenaments cromosòmics 8p23.1 Defensines Correlació Fusió gènica Expansió gènica Mosaicisme Inversions Primats Variant estructural Variant en número de còpia o CNV Família gènica FAM90A Duplicacions segmentàries Genomic disorder Polymorphism Ka/Ks FISH Real time PCR WGS SNPassoc Illumina 57

Page generated in 0.046 seconds