Disruptions in memory are a hallmark feature of several psychiatric diseases. These illnesses are often marred by an inability to recognize that a stimulus or event as been previously experienced, a phenomenon known as recognition memory. Previous study has demonstrated that cognitive disruptions reflect aberrant signaling, including disruptions in synaptic plasticity, in key regions of the brain, such as prefrontal cortex (PFC), hippocampus, and perirhinal cortex (PRh). However, in the case of recognition memory, how these disruptions arise and what specific plasticity mechanisms are involved is less clear. An understanding of the etiological factors underlying disruption and the synaptic processes involved in recognition will greatly advance the treatment and prevention of psychiatric disorders. As a result, the present thesis examined recognition memory in rodents in two experiments. In the first experiment, we blocked the endocytosis of AMPA receptors during the encoding, consolidation, or retrieval phase of object recognition memory using local PRh infusions of the cell membrane permeable Tat-GluA23Y interference peptide. Tat-GluA23Y infusion before the encoding and consolidation phases did not alter memory. In contrast, Tat-GluA23Y infusion prior to the retrieval phase significantly disrupted memory. These results indicate a distinct role for AMPA receptor endocytosis during a specific phase (retrieval) of visual recognition memory. In the second experiment, pregnant dams were treated with PolyI:C (4mg/kg, i.v.) on gestational day (GD) 15, and both the male and female offspring of these rats were tested as young adults in three different recognition memory tests: spontaneous novel object recognition, novel object location recognition, and object-in-place recognition. Male, but not female, rats were impaired in an object-in-place memory test that depends on processing between medial temporal lobe and PFC. However, neither male nor female rats were impaired on tests of simpler discriminations dependent on the medial temporal lobe. These findings support clinical studies demonstrating impaired object location binding in clinical populations and further demonstrate the plausibility of prenatal immune activation as an etiological factor in neurodevelopmental disease. Taken together, these results highlight the importance of a specific form of synaptic plasticity during the recognition of familiar stimuli and demonstrate that early life adversity can disrupt recognition memory processes.

Disruptions in memory are a hallmark feature of several psychiatric diseases. These illnesses are often marred by an inability to recognize that a stimulus or event as been previously experienced, a phenomenon known as recognition memory. Previous study has demonstrated that cognitive disruptions reflect aberrant signaling, including disruptions in synaptic plasticity, in key regions of the brain, such as prefrontal cortex (PFC), hippocampus, and perirhinal cortex (PRh). However, in the case of recognition memory, how these disruptions arise and what specific plasticity mechanisms are involved is less clear. An understanding of the etiological factors underlying disruption and the synaptic processes involved in recognition will greatly advance the treatment and prevention of psychiatric disorders. As a result, the present thesis examined recognition memory in rodents in two experiments. In the first experiment, we blocked the endocytosis of AMPA receptors during the encoding, consolidation, or retrieval phase of object recognition memory using local PRh infusions of the cell membrane permeable Tat-GluA23Y interference peptide. Tat-GluA23Y infusion before the encoding and consolidation phases did not alter memory. In contrast, Tat-GluA23Y infusion prior to the retrieval phase significantly disrupted memory. These results indicate a distinct role for AMPA receptor endocytosis during a specific phase (retrieval) of visual recognition memory. In the second experiment, pregnant dams were treated with PolyI:C (4mg/kg, i.v.) on gestational day (GD) 15, and both the male and female offspring of these rats were tested as young adults in three different recognition memory tests: spontaneous novel object recognition, novel object location recognition, and object-in-place recognition. Male, but not female, rats were impaired in an object-in-place memory test that depends on processing between medial temporal lobe and PFC. However, neither male nor female rats were impaired on tests of simpler discriminations dependent on the medial temporal lobe. These findings support clinical studies demonstrating impaired object location binding in clinical populations and further demonstrate the plausibility of prenatal immune activation as an etiological factor in neurodevelopmental disease. Taken together, these results highlight the importance of a specific form of synaptic plasticity during the recognition of familiar stimuli and demonstrate that early life adversity can disrupt recognition memory processes.

L’asthme sévère de l’enfant est une pathologie respiratoire chronique dont le traitement est difficile. L’épithélium bronchique à l’interface de l’organisme et de l’environnement, est un pivot central dans la maladie asthmatique. Le but de ce travail a donc été d’étudier l’épithélium bronchique de l’enfant asthmatique sévère.Dans un premier temps, j’ai développé un modèle de reproduction d’épithélium bronchique in vitro obtenu à partir de cellules épithéliales bronchiques issues de biopsies bronchiques d’enfants asthmatiques sévères. J’ai comparé ces épithélia obtenus chez l’enfant à ceux obtenus chez l’adulte. Nous avons spécifiquement étudié un marqueur inflammatoire important dans l’asthme sévère, le TSLP. J'ai montré 2 isoformes de TSLP ayant un rôle contraire, anti inflammatoire et proinflammatoire. Dans un deuxième temps, j’ai mis au point un modèle d’exacerbation d’asthme viro-induite. J’ai utilisé le modèle de culture et soumis les cellules à une stimulation Poly I:C. Les différentes cytokines sécrétées lors d’une exacerbation asthmatique virale ont été retrouvées augmentées dans notre modèle : CXCL8, CXCL10, CCL2, CXCL9 et RANTES. Enfin, j’ai étudié le propionate de fluticasone dans le modèle d’exacerbation asthmatique. Nous avons montré que l’effet de la fluticasone est différent entre les cellules épithéliales bronchiques issues de témoins et celles issues d’asthme sévère. Le modèle de stimulation viro-induite a permis d’étudier l’effet des corticoïdes inhalés sur l’épithélium bronchique et va permettre d’étudier les voies mécanistiques en jeu dans les exacerbations viro-induites, de tester d’autres molécules et proposer d’autres pistes thérapeutiques. / Severe childhood asthma is a chronic respiratory disease difficult to control despite treatment. Bronchial epithelium, at the interface between the body and the environment, is a central pivot in the asthmatic disease. The aim of this study was to examine the bronchial epithelium of severe asthmatic children. Initially, I developed a bronchial epithelium in vitro reproduction model obtained from bronchial epithelial cells from bronchial biopsies of severe asthmatic children. I compared these epithelia obtained in children with those obtained in adults. We specifically studied an important inflammatory marker in severe asthma,TSLP. I have highlighted the presence of two isoforms of TSLP which have an opposite role, anti-inflammatory for the short form and the long form for proinflammatory.Secondly, I developed an asthma exacerbation model of virus-induced. I used the culture model and challenged bronchial cells with poly I:C to. Different cytokines secreted upon viral asthma exacerbation were found increased in our model: CXCL8, CXCL 10, CCL2, RANTES and CXCL9.Finally, I have studied fluticasone propionate in the exacerbation asthmatic model. I studied cells from asthmatic and from non asthmatic children. Interestingly, we have shown that the effect of fluticasone is different between bronchial epithelial cells from non asthmatic children and those from severe asthma.The model of virus-induced stimulation was used to study the effect of inhaled corticosteroids on bronchial epithelium and will allow studying the mechanistic pathways involved in virus-induced exacerbations, testing other molecules and propose other therapeutic approaches.

V ANGLICKÉM JAZYCE Immunotherapy of ovarian carcinoma with dendritic cells Anticancer immunotherapy is a therapeutical strategy aimed at elicitation and maintenance of immune responses against cancer cells. In this study we have focused on immunotherapy of ovarian cancer, because it is one of the most common gynaecological tumors with poor prognosis and high mortality. Our immunotherapy protocol involves preparing dendritic cells (DC) from monocytes isolated from patient's peripheral blood, which are subsequently pulsed with irradiated cells of established ovarian cancer cell line. These immature pulsed DC are maturated and subsequently co-cultivated with autologous T lymphocytes. The aim of this study was to demonstrate, that DC are able to elicit specific immune response after addition of suitable mature agens in combination with apoptotic ovarian tumor cells. Our observations indicate that 24 hours are sufficient for induction of tumor cells apoptosis. Additionally, we have shown that DC successfully ingested most of the apoptotic tumor cells after 4 hours of co-incubation. Furthermore, we have found out that ingestion of apoptotic cells by dendritic cells, which are stimulated with polyI:C, inhibits maturation of DC and consequently also production of cytokines IL-12p70, IL-6 and TNF-α. Whereas...

<p>Sexually transmitted infections (STIs), especially HIV/AIDS and HSV-2, continue to be a devastating burden on societies around the world. The close link between HSV-2 and HIV-1, the role of inflammation in driving these infections, and the limited success and availability of prophylactic and therapeutic measures underscore the need for continued search of alternative means of protection. Characterization of endogenous antimicrobials, especially those local to the female genital tract and actively regulating inflammatory and antiviral responses, could be beneficial for microbicidal trials. Although regulators of mucosal immunity, such as serine antiproteases, trappin-2 and elafin (Tr/E), have been associated with resistance to HIV-1, their antiviral activity remains poorly understood. Thus, the research presented in this thesis centers on characterization of antiviral properties of Tr and E individually and their potential mechanisms in defense against HSV-2 and HIV-1 in the female genital mucosa. Chapter 2 examines Tr/E contribution to antiviral host defense responses elicited by a synthetic mimic of viral dsRNA, polyI:C. Chapter 3 documents the presence and characteristics, including potential mechanisms, of antiviral activity of Tr/E against in vitro and in vivo HSV-2 infection. Chapters 4 and 5 determine the contribution of Tr/E to the natural anti-HIV-1 protection of CVL and structural characteristics, mode(s) of action, and cellular distribution/localization of antiviral Tr/E proteins. Therein, we present novel properties of each Tr/E by demonstrating their inhibitory and multiple effects against both HSV-2 and HIV-1. These effects appear to be mediated either through virus or cells and be associated with altered viral attachment/entry, transcytosis and infection, innate viral recognition, modulated inflammation and increased antiviral protection of cells. Reported antiviral activity of Tr/E was also contextual and exerted, at least in HEC-1A cells, via autocrine/paracrine mode and depended on elafin’s nuclear localization and its unmodified N-terminus. Tr/E may represent viable candidates for further studies in the field of STIs.</p> / Doctor of Philosophy (PhD)