Chez les espèces aviaires, le stockage des spermatozoïdes s’étend sur plusieurs semaines principalement au niveau du réservoir de la jonction utéro-vaginale, contenant les tubules de stockage des spermatozoïdes (SST). Les mécanismes impliqués dans ce processus restent indéterminés. L’effet de l’insémination artificielle (IA) a été évalué sur le protéome du fluide utérin (FU), des protéines cibles et des glycanes dans les SST, provenant de poules possédant une longue (F+) ou courte (F-) durée de stockage. La longue durée de stockage est associée à une abondance relative dans le FU après IA des protéines exosomales (ANXA4, ANXA5), des protéoglycanes (TSKU), des protéines liant les protéoglycanes (HAPLN3, FN1, VTN), des transporteurs de lipides (VTG1, VTG2, APOA1, APOA4, APOH), et des protéines matricielles de la coquille (OCX32). Au contraire, la faible capacité de stockage est associée à la régulation après IA des protéines immunitaires (PIGR, immunoglobulines) ou pro-inflammatoire (LTA4H), des protéases (XPNPEP1), des chaperones (HSPA8), des mucines (MUC5AC, MUC5B), et de l’ovalbumine (OVALY). Au niveau des SST, les protéines matricielles de la coquille (OC-116, OCX36, OC-17) ont été identifiées dans l’épithélium et la lumière. La longue durée de stockage est associée à la sécrétion luminale de résidus Glc/GlcNAc, à la mobilisation apicale de protéines exosomales (ANXA4), et la non-activation des voies métaboliques impliquant les protéines PIGR, HSPA8, et ANXA5 dans les SST. En conclusion, la composition protéique du FU et des SST requièrent des régulations spécifiques après IA certainement pour garantir le stockage des spermatozoïdes. / In avian species, the sperm storage mainly takes place in uterovaginal sperm storage tubules (SST) during several weeks. Mechanisms implied in this process are not fully understood. The effect of artificial insemination (AI) has been evaluated on the uterine fluid (UF) proteomic composition, and on SST candidate proteins, from hens exhibiting long (F+) or short (F-) sperm storage duration. Long sperm storage duration was associated with the relative abundance in UF after AI of proteoglycans (TSKU), proteoglycan binding proteins (HAPLN3, FN1, VTN), lipid transporters (VTG1, VTG2, APOA1, APOA4, APOH), and eggshell matrix proteins (OCX32). In contrast, poor sperm storage ability was associated with the regulation of immune factors (PIGR, immunoglobulins), pro-inflammatory factors (LTA4H), proteases (XPNPEP1), chaperone (HSPA8), mucins (MUC5AC, MUC5B), and ovalbumin related protein Y (OVALY). At the level of SST, eggshell matrix proteins (OC-116, OCX36, OC-17) were identified in SST cells and lumen. Long sperm storage duration was associated in SST with the luminal secretion of Glc/GlcNAc residues, ANXA4 apical mobilization, and non-activation of metabolic pathway implying PIGR, HSPA8, and ANXA5. In conclusion, the proteomic composition of UF and SST require specific regulation after insemination, most probably to guarantee the success of sperm storage process.

A la suite des catastrophes nucléaires d’importantes quantités de radionucléides ont été rejetés dans l’environnement. Le Strontium 90 (90Sr) fait partie de ces rejets. Du fait de sa demi-vie de 29 ans, c’est un polluant persistant qui conduit à la contamination des populations vivant autour des territoires contaminés via l’ingestion chronique de faibles quantités de ce radionucléide. Les études épidémiologiques ont mis en évidence des effets au niveau du système immunitaire, du système hématopoïétique et de la physiologie osseuse chez l’homme. Le 90Sr qui s’incorpore principalement dans l’os pourrait contribuer à l’apparition de ces effets. Le but de ce travail a été de comprendre quels sont les mécanismes d’action du 90Sr qui permettent d’expliquer de tels effets. Un premier modèle in vitro utilisant une lignée de cellules stromales murines (MS5) contaminées par le milieu de culture à 1 ou 10 kBq.ml-1 a été utilisé. Il a permis de montrer que le 90Sr était capable d’induire des cassures double-brin de l’ADN dès 30 minutes d’exposition avec une induction de la senescence et une altération de la fonction de support aux progéniteurs hématopoïétiques. Dans le deuxième modèle in vivo d’effet dose, des souris Balb/c ont été contaminées durant 24 semaines à des concentrations de 90Sr de 4, 20 et 100 kBq.l-1 dans l’eau de boisson. Cette expérience a permis d’observer une augmentation des marqueurs de la résorption osseuse en fonction de la contamination au 90Sr ainsi et une augmentation de l’expression génique des enzymes impliquées dans la défense antioxydante. Une augmentation de p21, marqueur de la senescence et une diminution d’IL-6 ont également été observées. Les implications de ces résultats sur la physiologie osseuse, le système immunitaire et hématopoïétiques sont discutées. Globalement, l’ensemble de ce travail complète les données déjà existantes sur le 90Sr et permet de mieux comprendre les mécanismes d’action du 90Sr sur les cellules stromales médullaires qui sont au centre de la régulation immuno-hématopoïétique. / Abstract : After nuclear disasters, large amounts of radionuclides were released into the environment. Strontium 90 (90Sr) is part of these wastes. Because of its half-life of 29 years, it is a persistent pollutant which leads to the contamination of surrounding populations through the chronic ingestion of low quantities of this radioelement. Epidemiologic studies have demonstrated some effects on immune system, hematopoietic system and bone physiology in humans. 90Sr accumulates mostly in bones and could contribute to the appearance of such effects. The aim of this work is to understand the action mechanisms which could explain the previous observations. In the first in vitro model, a murine stromal cell line (MS5) contaminated through the culture medium with 1 or 10 kBq.ml-1 of 90Sr was used. Thank to this model, an increased number of DNA double-strand breaks in cells after 30 minutes of exposure, a senescence induction and a modification in the support of hematopoietic progenitors were observed. In the second model, Balb/c mice were contaminated during 24 weeks through drinking water containing 90Sr at 4, 20 and 100 kBq.l-1. Both an increase in genic expression of bone resorption markers and in antioxydative enzymes were observed. An increase in p21 expression, marker of senescence, and a decrease in IL-6 were also seen. The implications of these results on bone physiology, immune and hematopoietic systems are discussed. As a whole, all this work completed the preexistent data about 90Sr and contributes to a better understanding of the action mechanisms of 90Sr on marrow stromal cells which have a pivotal function in the regulation of the immune and hematopoietic system.

Pancreatic cancer is known to be one of the most life-threatening cancers characterized by aggressive local invasion and distant metastasis. The high basal level of autophagy in pancreatic cancer may be responsible for the low chemotherapeutic drug response rate and poor disease prognosis. However, the clinical application of autophagy inhibitors was unsatisfactory due to their toxicity and minimal single-agent anticancer efficacy. Hence, oncologists begin to consider the tumor microenvironment when exploring new drug targets. In the present study, the anti-tumorigenic mechanisms of two major phytochemicals derived from Chinese medicinal herbs had been investigated against pancreatic cancer development. Calycosin is a bioactive isoflavonoid of the medicinal plant Astragalus membranaceus. Our results have shown that calycosin inhibited the growth of various pancreatic cancer cells both in vitro and in vivo by inducing cell cycle arrest and apoptosis. Alternatively, calycosin also facilitated MIA PaCa-2 pancreatic cancer cell migration in vitro and increased the expression of epithelial-mesenchymal transition (EMT) biomarkers in vivo. Further mechanistic study suggests that induction of the Raf/MEK/ERK pathway and facilitated polarization of M2 tumor-associated macrophage in the tumor microenvironment both contribute to the pro-metastatic potential of calycosin in pancreatic cancer. These events appear to be associated with calycosin-evoked activation of TGF-β signaling, which may explain the paradoxical drug actions due to the dual roles of TGF-β as both tumor suppressor and tumor promoter in pancreatic cancer development under different conditions. Isoliquiritigenin (ISL) is a chalcone obtained from the medicinal plant Glycyrrhiza glabra, which can be a precursor for chemical conversion to form calycosin. Results have shown that ISL decreased the growth and EMT of pancreatic cancer cells in vitro, probably due to modulation of autophagy. ISL-induced inhibition of autophagy subsequently promoted reactive oxygen species (ROS) production, leading to induction of apoptosis in pancreatic cancer cells. Such phenomenon also contributed to the synergistic growth-inhibitory effect in combined treatment with the orthodox chemotherapeutic drug 5-fluorouracil. In addition, ISL-induced tumor growth inhibition in vivo was further demonstrated in a tumor xenograft mice model of pancreatic cancer. ISL promoted apoptosis and inhibited autophagy in the tumor tissues. Study on immune cells indicates that ISL could reduce the number of myeloid-derived suppressor cells (MDSCs) both in tumor tissue and in peripheral blood, while CD4+ and CD8+ T cells were increased correspondingly. In vitro test has revealed that ISL inhibited the polarization of M2 macrophage along with its inhibition of autophagy in M2 macrophage. These immunomodulating effects of ISL had reversed the pro-invasive role of M2 macrophage in pancreatic cancer.In conclusion, calycosin acts as a "double-edged sword" on the growth and metastasis of pancreatic cancer, which may be related to the dual roles of TGF-β and its influence on the tumor microenvironment. Alternatively, ISL consistently inhibited the growth and metastatic drive of pancreatic cancer through regulation of autophagy and reprogramming of the immune system. The differential modes of action of these compounds have provided new insights in the development of effective pancreatic cancer treatment adjuvants.

Actualmente el mundo nos ha demostrado que se encuentra en constante cambios. Cambios a los que miles de personas no nos encontramos preparados y que nos ha enseñado a valorar los recursos que la naturaleza nos provee. El Perú al igual que muchos países no es ajeno a la falta de cultura del cuidado del medio ambiente y a la tendencia de consumo de alimentos saludables. El presente trabajo se centra en este último punto, ya que a raíz de la actual pandemia que seguimos atravesando se ha identificado que la obesidad es un factor de riesgo que agrava a pacientes con COVID-19. En base a dicha premisa surge la idea de emplear un alimento alto en propiedades nutritivas y que fortalezcan el sistema inmunológico. Asimismo, se busca colaborar con agricultores peruanos y promover de esta manera el consumo de la alcachofa. Con la finalidad de medir el impacto de esta propuesta se realizó el siguiente trabajo de investigación. Se realizaron encuestas, entrevistas, generación de landing page y creación de post para obtener información. Dichos resultados, permitieron delimitar el tamaño del mercado, público objetivo y las estrategias a desarrollar para incursionar con un producto a base de alcachofa en el mercado peruano. Por otro lado, para el financiamiento que requiere el proyecto se tomarán dos inversiones, cuya tasa será menor al de los bancos, debido a que se encuentra en la fase de gestación y despegue. Para iniciar el desarrollo del proyecto se necesita un importe de 5895 nuevos soles, cuyo recupero se ve favorable, debido al mercado potencial identificado extraída de los experimentos realizados en el desarrollo del proyecto, permitió observar un desarrollo favorable con las acciones financieras y operativas para el proceso productivo y de venta de “Alcapulp”. Las proyecciones y los análisis financieros del proyecto demuestran flujos descontados del proyecto positivos, a la vez que permiten visualizar una buena relación entre costo y beneficio. De la misma manera, se exhibirá que los ratios financieros y períodos de recuperación de la inversión resultan favorables para la viabilidad del negocio. / Today, the world has shown us that it is constantly changing. Changes to which thousands of people are not prepared and that has taught us to value the resources that nature provides us. Peru, like many countries, is not unaware of the lack of a culture of environmental care and the tendency to consume healthy foods. This paper focuses on the latter point, since as a result of the current pandemic that we continue to experience, obesity has been identified as a risk factor that aggravates patients with COVID-19. Based on this premise, the idea of using a food high in nutritional properties and that strengthens the immune system arises. Also, it seeks to collaborate with Peruvian farmers and thus promote the consumption of artichokes. In order to measure the impact of this proposal, the following research work was carried out: Surveys, interviews, generation of landing pages and creation of posts to obtain information were carried out. These results made it possible to define the size of the market, the target audience and the strategies to be developed to enter the Peruvian market with an artichoke-based product. On the other hand, for the financing required by the project, two investments will be taken, whose rate will be lower than that of the banks, because it is in the gestation and take-off phase. To start the development of the project, an amount of 5,895 nuevos soles is needed, the recovery of which is favorable, due to the identified potential market extracted from the experiments carried out in the development of the project, it allowed to observe a favorable development with the financial and operational actions for the production and sale process of "Alcapulp". In addition, the financial forecasts show a positive cash flow and let us know the project has a good benefit cost ratio. Also, it will be demonstrated that the business has favorable financial ratios as well as a good recover time. / Trabajo de investigación

Previously, our lab demonstrated that heterologous immunity could result in either gain or loss of protective immunity and alteration in immune pathology following infection by a second un-related pathogen. One of the prototypical models to study T cell-mediated heterologous immunity involves two distantly related arenaviruses, namely lymphocytic choriomeningitis virus (LCMV) and Pichinde virus (PV). Each virus encodes a cross-reactive CD8 epitope that has six out of eight in amino acid (aa) similarity with respect to its counterpart at the position 205-212 of the nucleoprotein (NP205). Heterologous challenge between LCMV and PV results in 1) expansion of the cross-reactive NP205-specific CD8 T cell responses and alteration of the immunodominance hierarchy and 2) partial protective immunity (heterologous immunity). Our lab showed that cross-reactive NP205-specific CD8 T cell receptor (TCR) repertoires become extremely narrowed following a heterologous challenge between LCMV and PV. Therefore, I questioned if LCMV NP205 epitope escape variants could be isolated during a dominant but narrowed crossVI reactive NP205-specific CTL response. In the first part of my thesis, I describe the isolation of a LCMV NP-V207A CTL escape variant in vivo using PV-immune animals challenged with LCMV clone 13. The LCMV NP-V207A variant contains a point mutation, which results in the switching of valine to alanine at the third non-anchoring residue of the LCMV NP205 CD8 epitope. Immunization of mice with the LCMV NP-V207A variant results in a significantly diminished cross-reactive NP205-specific CD8 T cell response. This suggests that the point mutation is responsible for the loss in the immunogenicity of the LCMV NP205 CD8 epitope. In addition, an in vitrorescued(r) recombinant LCMV variant (r/V207A) that encodes the original mutation also induces a highly diminished cross-reactive NP205-specific CD8 T cell response in mice. In agreement with the result obtained from the intracellular cytokine assays (ICS), MHC-Ig dimers loaded with the LCMV NP205 (V-A) peptide could only detect a minute population of cross-reactive NP205-specific CD8 T cells in mice infected with r/V207A variant virus. All the data indicate that the point mutation results in a significant loss in immunogenicity of the LCMV NP205 CD8 epitope. So far, no direct link between the cross-reactive NP205-specific CD8 T cells and heterologous immunity had been established in this system. Therefore, we immunized mice with either LCMV WT or the LCMV NP-V207A variant virus and showed that a significant loss of heterologous immunity is associated with the group immunized with LCMV NP-V207A variant virus. Again, r/V207Aimmune animals also displayed a significant loss in heterologous immunity following PV challenge. This suggests that the cross-reactive NP205-specific CD8 T cells mediate the majority of heterologous immunity between LCMV and PV in vivo. In comparison to the PV-immune control group, PV clearance kinetics mediated by the cross-reactive NP205-specific CD8 T cells were significantly delayed. Finally, these data also suggest that bystander activation plays very little role in heterologous immunity between LCMV and PV. Many studies in murine systems and humans suggest that cross-reactive T cells are often associated with immune pathology. We showed that in mice that were sequentially immunized with PV and LCMV (PV+LCMV WT double immune mice), there was a development of a high incidence and high level of immune pathology known as acute fatty necrosis (AFN) following a final PV challenge. The data suggest that these cross-reactive NP205-specific CD8 T cells might play an important role in immune pathogenesis. Therefore, we asked if the cross-reactive NP205-specific CD8 T cells play a role in immune pathogenesis by comparing the incidence of AFN between the (PV+LCMV WT) and the (PV+LCMV NP-V207A) double immune mice following a final PV challenge. In agreement with our hypothesis, the result showed the (PV+LCMV NP-V207A) double immune mice developed a significantly lower incidence of AFN compared to the (PV+LCMV WT) double immune mice. However, linear correlation studies comparing the frequency of different antigen-specific CD8 T cell populations within the (PV+LCMV WT) double immune mice before challenge and the severity of AFN following the PV challenge suggest that two opposing antigen-specific CD8 T cell populations are involved in determining the final outcome of the immune pathology. The PV NP38-45-specific CD8 T cell response (PV NP38) appears to be more protective than the cross-reactive NP205-specific CD8 T cell response. In addition, a positive linear correlation between the ratio of cross-reactive NP205 to PV NP38 and the severity of AFN seem to suggest that these cross-reactive populations are important contributors to immune pathogenesis. Peptide titration studies examining the functional avidities to different antigenic specificities suggest that both populations consist of high avidity TCR and peptide MHC (TCR:pMHC) interactions. However, skewing within the cross-reactive NP205 specific CD8 T cell response towards the LCMV NP205 epitope response in one of the (PV+LCMV WT) double immune mice suggests that cross-reactive NP205 specific CD8 T cells could constitute a sub-optimal response to a PV challenge. In summary, I questioned what might be some of the immunological consequences of heterologous immunity in this model. First of all, we have established a direct link between the cross-reactive NP205-specific CD8 T cell response and heterologous immunity in LCMV and PV. Second of all, I demonstrated that a LCMV NP205 epitope escape variant could be selected in vivo under the conditions of heterologous immunity. In addition, I showed that PV clearance kinetic was significantly delayed in cross-reactive NP205-mediated heterologous immunity as compared to homologous challenge. Finally, we demonstrated that cross-reactive NP205-specific CD8 T cells could play an important role in immune pathogenesis in this model. However, correlation data indicate that two opposing antigen-specific CD8 T cell populations could ultimately decide the outcome and magnitude of immune pathology in each individual mouse. All the data presented above strongly suggest that the cross-reactive NP205 CD8 T cells play a crucial role in immune pathology in this model system by 1) interfering with the regular establishment of immunodominance hierarchy orders, or 2) exhibiting a sub-optimal protective immunity due to the nature of the cross-reactive epitope.

Vitiligo is an autoimmune disease in which CD8+ T cells selectively destroy melanocytes, leading to a patchy, disfiguring depigmentation of the skin. Our group and others have highlighted the central role of IFN-γ-dependent chemokines in the progression of disease; however, IFN-γ is also reported to have pleiotropic effects on melanocyte biology. We examined whether IFN-γ has a direct role in melanocyte killing. We tested the T-cell effector functions IFN-γ, Fas ligand and perforin by deleting them from autoreactive T cells used to induce vitiligo in mice. We found that disease incidence, disease severity and T cell accumulation in the skin was reduced in mice receiving adoptive transfer of either IFN-γ deficient or Fas ligand deficient gp100-specific T cells; however, perforin was dispensable and led to increased disease scores and T cell accumulation. To determine how melanocytes are affected by IFN-γ signaling during vitiligo, we performed single-cell RNA-sequencing on suction blister biopsies obtained from vitiligo and healthy subjects. We discovered that integrin expression and TGFb2 signaling was decreased only in lesional melanocyte transcriptomes. Moreover, melanocytes appear to participate in their own demise by increasing HLA expression and recruiting effector cells through the chemotactic ligand CCL18. The loss of melanocyte retention factors may explain their clean disappearance from the skin during keratinocyte turnover. Taken together, we believe IFN-γ production by autoreactive T cells in the skin leads to clean loss of melanocytes by downregulation of melanocyte retention factors and by increasing their potential to be detected by effector cells during vitiligo.

The primary purposes of this dissertation were to explore relationship between cell free DNA (cf-DNA), creatine kinase (CK), C-reactive protein (CRP), vertical jump testing delayed onset muscle soreness (DOMS) in response to a high-volume resistance training protocol, and to assess the sensitivity of cf-DNA to different resistance training volume loads. The secondary purpose was to examine the relationship between cf-DNA and relative strength. Study 1 was an exploratory attempt to discover relationships between cf-DNA, CK, CRP, delayed onset muscle soreness, and performance variables. Seventeen resistance trained males were recruited, 9 were randomly assigned to receive BCAAs while 8 received a placebo. Participants performed a high-volume resistance training session consisting of the back squat and bench press. Blood was drawn to measure serum cf-DNA, CK, and CRP levels prior to the training session, with cf-DNA collected immediately post, and CK and CRP at 24hr and 48hrs post. Self-reported DOMS on a scale of 1 to 10 was collected prior to training on day 2, day 3, and day 4. SJH, CMJH, and BOSCO were collected on day 1, day 3, and day 4. Fifty-seven correlations were run to explore the relationships between variables. Only the correlation between %Δ DOMS 48hr and %Δ CRP 48hr in the non-supplement group was significant (p = 0.02). The second study, designed to assess the sensitivity of cf-DNA to different resistance training volume loads, consisted of a high-volume resistance training protocol. Blood was drawn immediately before the resistance training session (T1), immediately after the third lifting set (T2), and immediately after the sixth lifting set (T3). cf-DNA increased significantly from T1 to T2 (p < 0.01) and T1 to T3 (p < 0.01). The linear regression model used to examine the capabilities of relative strength to predict %Δ cf-DNA from T1 to T3 was significant (p = 0.04). The results of this study demonstrate the short response time of cf-DNA in relation to variations in resistance training volume-load, suggesting it may be a valuable marker in monitoring the immune response to volume-load. Results also demonstrated the positive relationship between relative strength and %Δ cf-DNA.

Heavy chain isotype switch recombination is preceded by the appearance of RNA initiating 5' of the specific switch region which will undergo recombination. In an effort to understand the potential function of germline transcripts in switch recombination and the degree to which the regulation of germline transcripts correlates with the regulation of switching, we studied this process in the murine B-lymphoma cell line I.29μ, which in the presence of bacterial lipopolysaccharide (LPS) switches primarily to IgA and less frequently to IgE. Levels of α-germline transcripts initiating upstream of α switch (Sα) sequences are elevated in clones of this line which switch well as compared to clones which switch less frequently. TGFβ1 has been shown to increase α-germline transcripts and switching to IgA expression in LPS-stimulated murine splenic B-cells. We now demonstrate in I.29μ cells that TGFβ also increases switching to IgA and increases the level of α-germline transcripts 5 to 9 fold. Nuclear run-on analysis shows that this increase is at the level of transcription. Thus, TGFβ appears to direct switching to IgA by inducing transcription from the unrearranged Sα- CαDNA segment. Germline α RNA is quite stable in I.29μ cells, having a half life of about 3 to 5 hours, and we find only slight stabilization in the presence of TGFβ. Levels of ε-germline transcripts are not increased by TGFβ . IL-4, which modestly increases switching to IgA in I.29μ cells, slightly increases trancription of α-germline RNA. However, we present evidence suggesting that endogenously produced IL-4 may also act at additional levels to increase switching to IgA. IFNγ, which reduces IgA expression in these cells, also reduces the level of α-germline transcripts. IFNγ also reduces the level of ε-germline transcripts induced by IL-4. Our results support the hypothesis that the regulation of transcription of particular switch sequences by cytokines in turn regulates the specificity of recombination. In studies aimed at identifying other signalling pathways that promote class switching, we discovered that inhibitors of the nuclear enzyme poly(ADP-ribose) polymerase (PARP) increase lipopolysaccharide (LPS)-induced switching to IgA in the B cell lymphoma I.29μ and to IgG1 in LPS + IL-4-treated splenic B cells. PARP, which binds to and is activated by DNA strand breaks, catalyzes the removal of ADP-ribose from NAD+ and poly(ADP-ribosylation) of chromatin-associated acceptor proteins. This enzyme is believed to function in cellular processes involving DNA strand breaks as well as in modulating chromatin structure. In I.29μ cells, PARP inhibitors increase IgA switching by day 2 and cause a 5-fold average increase in switching on day 3 as assayed by immunofluorescence microscopy. The PARP inhibitor, nicotinamide, also causes a reduced intensity of hybridization of Cμ and Cα specific probes to genomic DNA fragments containing the expressed VDJ-Cμ and the unrearranged Sα - Cα segments, respectively, indicating that PARP inhibition increases rearrangment of these fragments. Induction of switching by PARP inhibitors is not mimicked by treatment with cAMP analogs or reduced by inhibitors of protein kinase A (PKA). Induction of switching by PARP inhibitors does not appear to involve increased levels of transcription of the unrearranged Cα gene, although TGFβ is required for optimal induction by PARP inhibitors, consistent with a requirement for transcription of the unrearranged CH gene. PARP inhibitors do not overcome the requirement for endogenously produced IL-4.

Le mélanome métastatique reste un enjeu majeur de santé publique. Les avancées fulgurantes de ces dernières années ont permis d’améliorer la prise en charge thérapeutique, notamment avec l’arrivée des anticorps bloquant ou agonistiques ciblant les molécules de co-inhibition ou de co-stimulation. Cependant, certains patients sont réfractaires à tout traitement. Il est donc nécessaire de mettre en évidence l’importance de certains paramètres immunologiques permettant d’améliorer le suivi des patients de stade III à haut risque de récidive. De plus, il est primordial de découvrir des marqueurs prédictifs associés à la réponse à ces différents traitements immunomodulateurs. Nous avons identifié une association entre une fréquence élevée de CD45RA+CD4+ et de CD3-CD56- au sein des métastases ganglionnaires avec la survenue d’une récidive anticipée.Une forte expression de NKG2D à la surface des lymphocytes T CD8+, une faible proportion de Tregs ou une faible expression de PD-L1 à la surface des T circulants sont associées à une meilleure survie. Aussi, la mise en place d’un test in-vitro étudiant les réactivités fonctionnelles des lymphocytes infiltrant les tumeurs a permis de dégager l’importance de l’expression de CD95/Fas sur les T CD4+ circulants et de CD137/4-1BB sur les T CD8+ circulants dans la prédiction de la réponse à l’ipilimumab (anti-CTLA-4) et à la combinaison ipilimumab + nivolumab (anti-PD-1). Par ailleurs, le pattern d’expression des récepteurs de chimiokines à la surface des lymphocytes T périphériques permet de détecter les localisations métastatiques de mélanome. Cette étude a révélé également l’importance biologique de l’axe CCR9/CCL25 dans l’immunosurveillance naturelle anti-tumorale. / Metastatic melanoma (MM) is an unmet medical need. The development of immune checkpoint blockers (ICB) improved patient’s clinical outcomes. However, some patients still do not respond to these therapies. To adress these issues, we must find some immunological parameters which predict the relapse of high risk resected stage III melanoma patients. Moreover, it is an urgent need to identify some predicting parameters to these ICB. In our studies, high frequencies of CD45RA+CD4+ and CD3-CD56- in metastatic lymph nodes are associated with a short relapse-free survival. Higher expression of NKG2D on CD8 T cells, low Tregs and low PD-L1 expression on circulating T cells are associated with a prolonged overall survival.Furthermore, we designed an in-vitro test to assess intratumor lymphocytes reactivities to ICB and cytokines (IL-2 and IFNα2a). Low expression of CD95/Fas on CD4+ circulating T cells and high expression of CD137/4-1BB on circulating CD8+ T cells are associated with the response to ipilimumab (anti-CTLA-4) and to the combination ipilimumab + nivolumab (anti-PD-1), respectively. In addition, the chemokine receptor pattern expressed at the surface of circulating lymphocytes could predict the metastatic spreading of melanoma. In this last study, we demonstrated the critical role of CCR9/CCL25 pathway in the natural anti-cancer immune surveillance.

Antimicrobial proteins contained in the albumen represent maternal effects, including the non- genetic component allocated into the egg during its oogenesis. Especially for species, whose broods are exposed to environmental influences until completation, these proteins play a crucial role in the viability of embryos due to their potential to influence the risk of microbial infection, which is considered one of the main causes of reduced hatchability. Also, it is assumed that these proteins, beacause of their specific traits, may influence phenotype of chicks, especially its size and immunity in the early postembryonal stage. In my thesis I focused on three antimicrobial proteins of avian egg white - avidin, lysozyme and ovotransferrin, which vary in their antimicrobial activity. For a better understanding of causal relationships between the concentrations of these proteins in the albumen and their effect on hatching success or offspring phenotype, a series of manipulation experiments and correlative measurements were performed. These experiments were held on the eggs of two precocial species - Japanese Quail (Coturnix japonica) and Mallard (Anas platyrhynchos). Our results indicate a crucial role of antimicrobial proteins in reducing the risk of bacterial infection and their natural concentration...