L’ensemble des travaux psychiatriques actuels se concentre essentiellement sur l’aspect symptomatiquement de la dépression chez les sujets schizophrènes. A l’inverse, nous avons tenté d’étudier non pas la dépression clinique, mais les problématiques de perte dans les fonctionnements psychiques des sujets marqués par le processus schizophrénique. Autrement-dit, nous avons interrogé le rôle et les fonctions de la perte au sein d’un moi ayant perdu ses frontières et le sentiment de son existence, dans un fonctionnement psychique où les limites soi/non-soi sont aléatoires, les défenses narcissiques précaires ou inefficaces. A travers l’examen de la perte chez le schizophrène, c’est donc l’étude des diverses modalités de la relation d’objet et des affects associés dans cette pathologie que nous avons étudié. Il s’agissait donc de passer au-delà de l’aspect purement symptomatologique et phénoménologique de la dépression chez le sujet schizophrène pour interroger sa fonction au niveau métapsychologique. Nous nous sommes intéressés aux diverses opérations psychiques mises en œuvre par les sujets atteint de schizophrénie pour faire face aux divers problématiques de perte. Par problématiques de perte, nous entendons toutes les situations où le sujet a perdu un objet, ou doit y renoncer, que ce soit dans les problématiques de séparation d'avec l'objet primaire, l’abord de la position dépressive, de mélancolie, de deuil. Nous avons donc interrogé les articulations et intrications entre problématiques de perte et problématiques dissociatives.Notre recherche est animée par l’idée que la schizophrénie est un processus qui détruit les liens objectaux et les représentations d’objet mais surtout qui empêche d’en reconstruire de nouveaux, en cela il s’attaque à l’objectalité même. Persuadé que les schizophrénies procèdent d’une incapacité à utiliser le dipôle narcissisme-objet, nous souhaitions observer les diverses « constellations relationnelles » au sein des fonctionnements psychiques marqués par la schizophrénie, à travers leur représentations. Notre idée était que les différentes formes de schizophrénies témoignaient des différentes modalités d’approche de l’objet ou de la relation à l’objet.Notre première hypothèse postule que, plus les fonctionnements psychiques marqués par le processus schizophrénique sont habités par des représentations d'objet, même si ces objets sont partiels, persécuteurs, mal différenciés ou incestueux, plus la pensée reste « vivante » même si elle est désorganisée. Une seconde hypothèse postule que chez les sujets atteints par un processus schizophrénique il n'y a pas de possibilité d'élaborer les problématiques de perte, même si on observe de grandes différences individuelles. Cependant la présence d’éléments témoignant de problématiques de perte peut venir signer un assouplissement partiel des défenses psychotiques et révéler un fonctionnement de l’appareil psychique moins abrasé. Une sous-hypothèse propose l’idée que la reconnaissance de problématiques de perte est possible, chez certains sujets atteints de schizophrénie, le traitement de la perte diffère alors de celui du deuil ou de la mélancolie. Enfin une troisième hypothèse porte sur l’existence d’un processus mélancolique que nous pourrions repérer dans certaines formes de schizophrénies (les formes dysthymiques) qui ne peut pas se constituer véritablement pour autant. / Our thesis does not deal with clinical depression but with the issue of loss within the psychic functioning of patients marked by a schizophrenic process. By issues of loss we mean all situations in which the patient has lost something, but also separation, depression, melancholy and grief. In order to examine the standard metapsychological function and to observe the articulations and entanglements existing between issues of loss and dissociative problems we surveyed the functions of loss associated with a personality that had lost its sense of confines and existence beyond the purely symptomatic aspect of depression. Our first hypothesis is that the more psychic functions are marked by a schizophrenic process inhabited by object representations, even if these representations are partial, persecuting, poorly differentiated or incestuous, the more the thought remains " alive " even if it is disorganised. A second hypothesis is that in schizophrenic patients there is no possibility of developing issues of loss. The presence of depressive elements can however signal a partial easing of psychotic defenses. A sub-hypothesis is that the recognition of the problem of loss is possible in dysthymic patients but that the treatment differs from that aimed at grief and melancholy. A third hypothesis centres around the existence of a melancholic process in some schizophrenics (dysthymia). To test these hypotheses we studied the psychic functioning of twenty patients diagnosed as " schizophrenic "according to CIM 10. This was based on projective mediation tests (Rorschach and TAT) looking at differences and invariables associated with the treatment of loss and depression. We demonstrated the specificity of psychic functioning for each schizophrenic in terms of relationships, emotions and sensations relating to the issue of loss. Our results demonstrate that the functioning of patients affected by schizophrenia, far from remaining focused on one object tends instead to defend itself from the influence of the object upon the ego. Behind a more delusional and hallucinatory appearance the mental functioning of patients with paranoid schizophrenia and dysthymia is more disorganised, but paradoxically " more alive ", more driven by representations of objects that appear as an outward expression of less deadly psychic functioning, this despite the noisier symptoms in the form of simple undifferentiated or hebephrenic schizophrenia. Our work shows that if problems and depressive effects can be seen they lead to different defensive treatments which are invariably underpinned by denials. The presence of isolated depressive effects does not lead to recognisable problems associated with loss for the patient. We therefore conclude that if schizophrenics recognise situations of loss then that cannot be the work of psychic integration. This impossibility depends on the intensity of the destructive schizophrenic process and the capacity to implement a narcissistic reinvestment in itself, even if only transitory, albeit with significant individual differences. Finally, if we examine the outlines of the melancholy movements within our participants, they cannot be carried through to the end because of the inconsistency of the object lost, its potentially persecuting character and the absence of self/non-self limits.

Plasma membrane of T cells is abundant in diverse receptors and other molecules orchestrating immune responses. Numerous studies demonstrate that the localisation of proteins in the cell is non-random and that mislocalisation either in the context of plasma membrane at nanoscale or with respect to the cell interior can lead to the protein malfunction and subsequent aberrant T- cell response. In my first Ph.D. project we focused mainly on the role of the transmembrane domain length and amino acid composition, proximal sequences and the presence or absence of palmitoylation on the localisation of transmembrane adaptor proteins LAT, PAG and NTAL in T cells. We showed that plasma membrane localisation of PAG and NTAL is controlled by the amino acid composition of their TMD and is palmitoylation independent. We propose that NTAL localisation to the plasma membrane is, despite its suboptimal length, facilitated by the electrochemical asymmetry of its TMD. Among transmembrane adaptor proteins, LAT was the most interesting one. Dependency of LAT plasma membrane localisation on palmitoylation in combination with unusual amino acid composition of its TMD led us to investigate it in a separate project. My first author Ph.D. project was thus to elucidate the role of highly conserved helix-breaking amino acids,...

<p>Disertacija je posvećena re&scaron;avanju jednačina distributivnosti gde&nbsp;nepoznate funkcije pripadaju nekim poznatim klasama operacija agregacije&nbsp;i primeni dobijenih re&scaron;enja u teoriji korisnosti. Dobijeni rezultati se generalno mogu podeliti u tri grupe. Prvu grupu čine rezultati iz Glave 2 dobijeni re&scaron;avanjem jednačina distributivnosti između GM-operacija agregacije i&nbsp;oslabljenih uninormi, GM-operacija agregacije i oslabljenih nulanormi, kao i&nbsp;GM-operacija agregacije i operacija agregacije bez neutralnog i absorbujućeg&nbsp;elementa. Druga grupa rezultata, takođe iz Glave 2, je dobijena re&scaron;avanjem&nbsp;jednačina uslovne (oslabljene) distributivnosi neprekidne nulanorme u odnosu&nbsp;na neprekidnu t-konormu, i neprekidne nulanonorme u odnosu na uninorme iz&nbsp;<br />klasa U_min &cup;U_max. Treća grupa rezultata (Glava 3) je proistekla iz primene dobijenih rezultata o uslovoj distributivnosti nulanorme u odnosu na t-konormu&nbsp;u teoriji korisnosti.</p> / <p>This dissertation is devoted to solving distributivity equations involving some well-known classes of aggregation operators, and application&nbsp;the obtained results to utility theory. In general, the obtained results can&nbsp;be divided into three groups. The first group are results from Chapter 2 obtained by solving distributivity equations between GM-aggregation operators&nbsp;and relaxed nullnorm, GM-aggregation operators and relaxed uninorms, as&nbsp;well as GM-aggregation operators and aggregation operators without neutral&nbsp;and absorbing element. The second group are results, also from Chapter 2,&nbsp;obtained by solving conditional (relaxed) distributivity of continuous nullnorm with respect to &nbsp;continuous t-conorm, as well as continuous nullnorm&nbsp;with respect to uninorms from the classes U_min &cup; U_max. The third group are&nbsp;results (Chapter 3) arising from the application results on conditional distributivity of nullnorm with respect to t-conorm in utility theory.</p>

T-cell activation is a complex process crucial for a proper function of immune system. It has been extensively studied and its main features are well understood. However, some of the events involved in T-cell signalling are still unclear. After T-cell receptor stimulation, Src-family kinase Lck drives the initiation of signalling by tyrosine phosphorylation. Phosphorylation of several downstream targets is dependent on the redistribution of Lck to the different compartment of the plasma membrane, called lipid rafts. In lipid rafts, active Lck is juxtaposed and activates raft-resident substrates which then trigger downstream signalling. The critical in this process is the mechanism of Lck translocation to lipid rafts which has not been studied so far and represents the topic of great academic and clinical interests. Previously, we identified the adaptor protein RACK1 as a candidate protein mediating the redistribution of Lck to lipid rafts by linking it to the microtubular network. In this thesis, we analysed the structural features and functional role of RACK1 in its interaction with Lck. We show here, using the SYF cell lines expressing the wild type and various mutated forms of Lck, that intact SH3 or SH2 domains of Lck are required for an effective RACK1-Lck complex formation. We also documented...

Diss. (sammanfattning) Stockholm : Karol. inst., 2007. / Härtill 3 uppsatser.

Thesis (Ph.D. in Immunology) -- University of Colorado Denver, 2007. / Typescript. Includes bibliographical references (leaves 133-156). Free to UCD affiliates. Online version available via ProQuest Digital Dissertations;

Thesis (Ph. D.)--University of Washington, 2000. / Vita. Includes bibliographical references (leaves 139-193).

Submitted by Ana Paula Macedo (ensino@ioc.fiocruz.br) on 2013-10-03T12:26:40Z No. of bitstreams: 1 Carolina Valença Messias.pdf: 1326403 bytes, checksum: adde2666bf9c1e45634b4ea4926b6090 (MD5) / Made available in DSpace on 2013-10-03T12:26:40Z (GMT). No. of bitstreams: 1 Carolina Valença Messias.pdf: 1326403 bytes, checksum: adde2666bf9c1e45634b4ea4926b6090 (MD5) Previous issue date: 2012 / Fundação Oswaldo Cruz. Instituto Oswaldo Cruz. Rio de Janeiro, RJ, Brasil / A leucemia linfoblástica aguda de células T (LLA-T) e o linfoma linfoblástico de células T (LL-T) são proliferações malignas de precursores de células T em diferentes estágios de maturação. LLA-T e LL-T são considerados atualmente duas formas de uma mesma doença, a leucemia/linfoma linfoblástico de células T (LLL-T), por compartilharem características morfológicas, imunofenotípicas e genéticas. Como os blastos de LLL-T apresentam características similares às de timócitos normais, moléculas envolvidas na migração destas células podem também estar envolvidas na migração ou homing dos linfoblastos no curso da doença. Neste sentido, foi demonstrado recentemente que o receptor 1 de esfingosina-1-fosfato (S1P1) é essencial para a saída de timócitos do timo. No presente estudo, decidimos avaliar a expressão e o papel do S1P1 na migração de quatro linhagens celulares de LLA-T (HPB-ALL, MOLT-4, CEM e JURKAT) em resposta ao seu ligante fisiológico, a esfingosina-1-fosfato (S1P). Observamos que a linhagem HPB-ALL apresentou baixa expressão de RNAm de S1P1, enquanto MOLT-4 e JURKAT apresentaram uma expressão mediana e CEM apresentou altos níveis de expressão de RNAm para este receptor. Em ensaios funcionais de migração celular observamos que a capacidade migratória das linhagens frente a S1P foi diretamente relacionada ao nível de expressão gênica do receptor. A S1P induziu a migração das linhagens analisadas em diferentes concentrações até 100 nM, e inibiu a migração quando aplicada em altas concentrações (1000 nM). As respostas migratórias foram acompanhadas pela modulação do citoesqueleto de actina. Dependendo da concentração de S1P utilizada, observamos polimerização (menores concentrações) ou despolimerização (maiores concentrações) da actina. Além disso, o prétratamento das células com W146 (inibidor de S1P1) bloqueou a migração das linhagens frente à S1P em menores concentrações e induziu a migração frente à S1P em altas concentrações, sugerindo que a migração seja especificamente mediada por S1P1. Nossos resultados sugerem que as interações mediadas por S1P/S1P1 modulam a migração não apenas de precursores de células T normais, mas também de linfoblastos de LLL-T. Desta forma, a interação S1P/S1P1 pode ser considerada como alvo para possíveis estratégias terapêuticas frente a estas neoplasias. / T-cell acute lymphoblastic leukemia (T-ALL) and T-cell lymphoblastic lymphoma (TLBL) are malignant proliferations of T cell precursors at different stages of normal development. T-ALL and T-LBL are presently believed to represent two different forms of a single disease, the T-cell lymphoblastic leukemia/lymphoma (T-LLL), as they share morphological, immunophenotypic and genetic features. As T-LLL lymphoblasts present similar characteristics of normal T cell precursors, molecules involved on the migration of these cells might also be associated with migration and homing of T-ALL/LBL. In this context, the sphingosine-1-phosfate receptor 1 (S1P1), has been described as essential for mouse thymocyte migration and thymic egress. Herein, we evaluated the expression and role of S1P1 in four T-ALL cell lines (HPBALL, MOLT-4, CEM e JURKAT) in response to its physiological ligand, the sphingosine-1-phophate (S1P). We observed that HPB-ALL cells presented low expression levels of S1P1 mRNA, whereas MOLT-4 and JURKAT had medium levels and CEM showed high levels of S1P1 expression. In functional migration assays, we observed that the migratory response of the cells towards S1P was directly related with their expression levels of the receptor. S1P induced the migration of the cell lines analyzed in different concentrations up to 100 nM and inhibited cell migration at higher concentrations (1000 nM). Moreover, migratory responses were accompanied by the modulation of actin cytoskeleton. Depending on S1P concentrations, we observed actin polymerization (lower concentrations) or depolymerization (higher concentrations). Pre-treatment of the cells with W146 (a S1P1 inhibitor) blocked S1Pinduced migration at lower concentrations but induced migration towards S1P at high concentrations, suggesting that the migration is specifically mediated by S1P1. Our results suggest that interactions mediated by S1P/S1P1 can modulate cell migration of T-LLL blasts similarly to their normal T cell precursor counterparts. Accordingly, immune intervention upon this ligand/receptor interaction may be envisioned as a potential therapeutic strategy for these malignancies.

Virtual memory (VM) CD8+ T cells represent a population of antigen-inexperienced T cells with an apparent memory phenotype. In lymphoreplete germ-free mice VM CD8+ T cells represent 10-20% of all peripheral CD8+ T cells. Their origin correlates with the levels of self-reactivity where the main factor that determinates the T-cell fate decision is the strength of homeostatic signals. In the first part of this thesis, we demonstrated that VM CD8+ T cells and naïve CD8+ T cells had distinct TCR repertoire and T-cell subsets contained different clonotypes. Moreover, 'VM clones' were enriched among VM T cells and were also present in naïve T cells. In contrast, 'naïve clones' were almost exclusively detected in naïve T cells. Next, we characterized the signaling of particular OVA-reactive TCRs from both naïve and VM subsets. We confirmed that 6 out of 8 tested TCRs were responsive to Kb-OVA. In the last part of the thesis, we developed and optimized a qPCR-based method for the relative quantification of specific T-cell clonotypes prior to and during the immune response. This method will serve as a tool for studying the biology of particular VM and naïve T-cell subsets and their role during the immune response. Keywords: T-cell receptor, homeostatic signaling, self-reactivity, virtual memory cells, T cells

Chimeric antigen receptors (CARs) are artificial molecules composed of an antibody derived antigen recognition domain which is fused with the signal transduction domain derived from the physiological TCR. CAR technology used to transduce patients T-cells and endow them with the specificity to a certain surface antigen, has been a major breakthrough in cancer immunotherapy in the last decade. This strategy has been most successful for treating hematologic malignancies. Various CAR approaches and applications are currently tested mainly in the United States where many clinical trials have been launched. In contrast, in the Czech Republic, there are only a few teams focused on this topic with no clinical trials going on. During my work on this diploma thesis and in close collaboration with MUDr. Pavel Otáhal, PhD., who is working on implementation of CAR technology into the Czech clinics for the treatment of B-cell malignancies, individual functional CARs were prepared and tested. CAR expressing Jurkat T-cell lines were generated using a lentiviral vector transduction system. CAR functionality was determined by two different assays. We have shown that individual CARs are able to recognize the B-cell lineage specific antigens CD19 and CD20 and significantly up-regulate the activation molecule CD69 upon...