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1

Betz, Christine [Verfasser], and Oliver [Akademischer Betreuer] Einsle. "Structural characterization of the metal-binding ligands S100A8/S100A9 and S100B of the receptor for advanced glycation end products = Strukturelle Charakterisierung der metallbindenden Liganden S100A8/S100A9 und S100B des Rezeptors für Advanced Glycation End Products." Freiburg : Universität, 2013. http://d-nb.info/1115813455/34.

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2

Leukert, Nadja. "Molekulare Charakterisierung verschiedener Komplexformen der Calcium-bindenden Proteine S100A8 und S100A9." [S.l. : s.n.], 2003. http://deposit.ddb.de/cgi-bin/dokserv?idn=967777062.

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3

van, Hummel Annika Elise. "The Roles of S100A8 and S100A9 in Cartilage: Degradation and Formation." Thesis, The University of Sydney, 2014. http://hdl.handle.net/2123/11521.

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Osteoarthritis (OA) is a debilitating joint disease that increases in prevalence with age, with latest figures show that around 2.4 million Australians suffer from OA. There are currently no disease-modifying drugs available and due to poor management options, the number of joint replacement surgeries is increasing by nearly 10% per annum in Australia. S100A8 and S100A9 calcium-binding proteins are expressed by immune cells, and are involved in inflammatory situations, including inflammatory diseases such as rheumatoid arthritis, where there is an increase in circulating and local (synovial fluid) levels of S100A8 and S100A9. They are present in the body preferentially as a heterodimer (S100A8/S100A9) or less commonly as homodimers. Recently, S100A8 and S100A9 were found in bone and cartilage cells; however their roles in these tissues are still unknown. The aim of this research therefore was to determine the role(s) of S100A8 and S100A9 in cartilage degeneration and OA. The results presented in this thesis have provided insight into the role(s) of S100A8 and S100A9 in cartilage and in OA. S100A8 and S100A9 act as primers of cartilage degradation, through TLR4 and MAPK signalling pathways, but require a second messenger in order to achieve full biochemical breakdown. S100A8 is abundant in chondrocytes of human OA joints, but does not appear to be involved in non-inflammatory mouse models. S100A8, and to a lesser degree S100A9, are also abundant at joint margins and in osteophytes from human OA patients, and may play a role in chondrogenesis. The results presented in this thesis have determined some of the mechanisms of action of S100A8 and S100A9 in cartilage, however, the exact role of S100A8 and S100A9 in OA remain unclear, and further work will need to be performed to fully determine the significance of S100A8 and S100A9 in OA.
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4

Baker, Jonathan Richard. "S100A8 in development." Thesis, University College London (University of London), 2008. http://discovery.ucl.ac.uk/1444146/.

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S100 proteins are a family of Ca2+ binding EF-hand proteins. S100A8 is a cytosolic protein expressed in myeloid cells and epithelia where it forms a stable heterodimer with another S100 protein family member, S100A9. The S100A9 null mouse is viable and has no gross defect whereas the S100A8 null mouse is embryonic lethal. It was originally proposed that the S100A8 null mouse is lethal at E 9.0 in development due to lack of expression at E 6.5 in ectoplacental cone cells. This thesis shows that the S100A8 null phenotype is more complex than originally thought. S100A8 has a role in preimplantation development, which is previously unstudied. A small number of S100A8 null embryos survive to blastocyst but none survive implantation showing fatal compromise of S100A8 null embryos early in development. This thesis presents evidence that this lethality presents between fertilisation and E 2.5 of development. S100A8 also has a role in the murine decidua after implantation possibly key to normal murine development. S100A8 mRNA is highly expressed in maternal decidua yet S100A8 protein is not highly expressed. Foetal yolk sac cells do not express S100A8 mRNA yet they do stain positively for S100A8 protein. This thesis proposes that S100A8 protein is generated in the murine decidua and exported to the foetus where haematopoietic cells present the protein. The S100A8 protein has been shown to be expressed and stable independently of its myeloid partner, S100A9. These observations explain the discrepancy between the two SI00 null mouse phenotypes and add new insight to the S100A8 null phenotype.
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Raquil, Marie-Astrid. "Études des rôles pro-inflammatoires et prolifératifs des protéines S100A8 et S100A9." Thesis, Université Laval, 2008. http://www.theses.ulaval.ca/2008/25415/25415.pdf.

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6

Sikora, Kristin [Verfasser]. "RAGE-abhängige S100A8- und S100A9-Expression in humanen THP-1 Zellen / Kristin Sikora." Berlin : Medizinische Fakultät Charité - Universitätsmedizin Berlin, 2009. http://d-nb.info/1023749920/34.

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7

Ludwig, Stefan [Verfasser]. "Die S100-Proteine S100A8 und S100A9 sowie der Heterodimerkomplex S100A8/A9 im Serum und Plasma als Marker des Prostatakarzinoms : Untersuchungen zu präanalytischen Einflussfaktoren und zur diagnostischen Differenzierung zwischen benigner Prostatahyperplasie und Prostatakarzinom / Stefan Ludwig." Berlin : Medizinische Fakultät Charité - Universitätsmedizin Berlin, 2008. http://d-nb.info/1023022486/34.

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8

Laouedj, Malika. "Effets des protéines S100A8 et S100A9 dans la différenciation cellulaire dans la leucémie myéloïde aiguë." Doctoral thesis, Université Laval, 2017. http://hdl.handle.net/20.500.11794/27761.

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Tableau d’honneur de la Faculté des études supérieures et postdoctorales, 2016-2017
Les leucémies myéloïdes aiguës (LMA) sont des hémopathies rares, mais très agressives. Elles résultent d’un dérèglement du processus d’hématopoïèse qui se caractérise par une prolifération incontrôlée de cellules sanguines immatures engagées dans la lignée myéloïde. En dépit des traitements actuels qui reposent sur l’utilisation d’agents chimiothérapeutiques ciblant les cellules en prolifération, le pronostic des patients souffrants de LMA est très sombre. En effet, seuls 30% des patients souffrants de LMA survivent au-delà de 5 ans suivant la prise en charge thérapeutique. L’identification des acteurs participant au développement et au maintien des LMA est donc cruciale pour l’élaboration d’une stratégie thérapeutique efficace et ciblée. S100A8 et S100A9 sont des protéines fixatrices de calcium exprimées par les neutrophiles et les monocytes. Ce sont des alarmines jouant des rôles clés dans l’inflammation et dans des pathologies causées par une inflammation excessive. Les protéines S100A8 et S100A9 exercent également de multiples fonctions dans divers tumeurs solides. Elles favorisent la formation de niche pré-métastasique et inhibe la réponse immunitaire antitumorale. Une analyse du génome par séquençage a mis en évidence que S100A8 et S100A9 sont fortement exprimées chez les patients atteints de LMA. De plus, l’expression de la protéine S100A8 chez les patients souffrants de LMA serait corrélée avec un faible taux de survie. Principalement étudiées dans les tumeurs solides, les fonctions des protéines S100A8 et S100A9 dans les néoplasies hématologiques telles que les leucémies sont très peu documentées. Dans ces travaux de thèse, nous nous sommes donc intéressés aux rôles exercés par les protéines S100A8 et S100A9 dans les leucémies myéloïdes aiguës. À l’aide d’un modèle murin de LMA induit par la surexpression des facteurs HOXA9 et MEIS1 dans des cellules souches/progénitrices hématopoïétiques, nous avons démontré l’existence d’une fraction de cellules exprimant les protéines S100A8 et S100A9. Celle-ci est également retrouvée chez les patients atteints de leucémies aiguës myélomonocytaires et monocytaires (M4-M5 d’après la classification FAB). Les études menées in vivo et in vitro révèlent que la protéine S100A9 induit la différenciation des cellules leucémiques, tandis que la protéine S100A8, préviens l’effet de S100A9 permettant de maintenir ainsi le phénotype immature des cellules LMA. Le traitement par la protéine recombinante S100A9 permet d’accroitre la maturation des cellules LMA, diminue leur prolifération et prolonge la survie des souris LMA. De la même façon le traitement par les anticorps anti-S100A8 provoque un effet similaire au traitement par la protéine S100A9. Nos résultats suggèrent que de forts ratios de S100A9 sur S100A8 sont requis pour induire la différenciation des cellules LMA. Le mécanisme intracellulaire par lequel S100A9 induit la différenciation des cellules leucémiques a également été étudié dans le cadre de cette thèse. Nous avons identifié que S100A9 via la liaison au récepteur TLR (Toll-like receptor) active les voies de signalisations Mitogen Activated Protein Kinase p38, Jun N-terminal Kinase et extracellular signal-regulated kinases 1 et 2 et provoque la différenciation des cellules leucémiques. Les essais menés sur des cellules primaires de patients malades ont permis de confirmer la capacité de S100A9 et de S100A8 à réguler la différenciation des cellules leucémiques. En somme, les données présentées dans cette thèse contribuent à une meilleure compréhension des rôles des protéines S100A8 et S100A9 dans la différenciation des cellules myéloïdes. Par ailleurs, nos données permettent également d’entrevoir les bénéfices thérapeutiques liés au blocage de S100A8 ou à l’augmentation de S100A9 dans les LMA.
Acute myeloid leukemias (AMLs) are rare but still aggressive hematological diseases. They are the result of a perturbed hematopoietic process characterized by an uncontrolled proliferation of hematopoietic cells committed to the myeloid lineage. Despite current therapy based on chemotherapeutic agents, aimed at killing proliferating cells, prognosis of AML patients is dismal and only 30 % of patients survived beyond 5 years. Identification of actors involved in the initiation and sustaining LMA is crucial to the development of efficient and targeted therapy strategy. S100A8 and S100A9 are calcium-binding proteins predominantly expressed by neutrophils and monocytes, and play key roles in both normal and pathological inflammation. Recently, both proteins were found to promote tumor progression through the establishment of pre-metastatic niches and to inhibit antitumor immune responses. Although S100A8 and S100A9 have been studied in solid cancers, their functions in hematological malignancies remain poorly understood. However, S100A8 and S100A9 are highly expressed in acute myeloid leukemia (AML), and S100A8 expression has been linked to a poor prognosis in AML. Although the roles of these proteins were studies in solid tumor, little is known in their functions in hematological malignancies. We studied in this thesis the role of S100A8 and S100A9 in acute myeloid leukemia. Using AML mouse model of AML surexpressing HOXA9 and MEIS1 in hematopoietic stem and progenitor cells, we identified a small subpopulation of cells expressing S100A8 and S100A9. This subpopulation was consistently found in AML samples from patients with myelomonocytic and monocytic leukemias (M4 and M5 according FAB classification). In vitro and in vivo analyses revealed that S100A9 induces AML cell differentiation, whereas S100A8 prevents differentiation induced by S100A9 activity and maintains AML immature phenotype. Treatment with recombinant S100A9 proteins increased AML cell maturation, induced growth arrest, and prolonged survival in an AML mouse model. Interestingly, anti-S100A8 antibody treatment had effects similar to S100A9 therapy in vivo, suggesting that high ratios of S100A9 over S100A8 are required to induce differentiation. In this thesis, the mechanism of S100A9 leading to differentiation of leukemic cells was also study. Our in vitro studies on the mechanisms/pathways involved in leukemic cell differentiation revealed that binding of S100A9 to toll-like receptor 4 (TLR4) promotes activation of p38 mitogen-activated protein kinase, extracellular signal-regulated kinases 1 and 2, and Jun N-terminal kinase signaling pathways, leading to myelomonocytic and monocytic AML cell differentiation. Overall, our findings indicate that S100A8 and S100A9 are regulators of myeloid differentiation in leukemia and have therapeutic potential in myelomonocytic and monocytic AMLs.
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9

Defrêne, Joan. "Fonctions des protéines S100A8 et S100A9 dans la réponse inflammatoire associée aux maladies auto-immunes." Doctoral thesis, Université Laval, 2020. http://hdl.handle.net/20.500.11794/66869.

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De nos jours, les maladies auto-immunes concernent une part grandissante de la population mondiale et s’accompagnent d’une comorbidité importante, mais aussi d’un lourd fardeau économique. Parmi ces maladies les plus courantes, on distingue l'arthrite rhumatoïde et le psoriasis affectant respectivement les articulations et la peau et qui ne possèdent toujours pas de traitements curatifs. Dans la pathogenèse de ces maladies, une forte réponse inflammatoire est notamment générée et entretenue, contribuant ainsi à la dégradation des tissus ciblés. De nombreux marqueurs de l’inflammation sont sécrétés dans ces tissus, dont les protéines S100A8 et S100A9 qui sont deux motifs moléculaires associés aux dommages cellulaires. Ces deux protéines sont majoritairement exprimées par les neutrophiles et les cellules myéloïdes activées ainsi que les kératinocytes. Plusieurs études démontrent des propriétés pro-inflammatoires pour S100A8 et S100A9. S100A9 stimule la sécrétion de cytokines pro-inflammatoires par les neutrophiles et les monocytes. La protéineS100A8 est chimiotactique pour les neutrophiles et les monocytes et sa neutralisation in vivo diminue le recrutement de leucocytes dans l’inflammation aiguë. En revanche, des études suggèrent des fonctions anti inflammatoires pour S100A8. Son expression est notamment induite par l’interleukine 10 et les glucocorticoïdes. De plus, S100A8 est sensible à l’oxydation et sa forme oxydée possède des fonctions anti inflammatoires. Cependant, les fonctions de ces deux protéines dans le développement de l’inflammation associées aux maladies auto-immunes sont peu connues. Nous avons effectué la première caractérisation des souris déficientes pour S100a8 et démontré que la protéine S100A8 contrôle la différenciation des cellules myéloïdes et leur capacité à moduler la réponse inflammatoire. À l’aide du modèle d’arthrite induite par le collagène, nous avons démontré que S100A8 est anti-inflammatoire. Elle diminue l’infiltration de neutrophiles et la sécrétion de cytokines pro-inflammatoires dans les pattes. Également, nous avons démontré que S100A8 atténue l’activité des ostéoclastes in vitro et invivo. Le traitement avec un anticorps contre la protéine S100A8 nous a permis de démontrer que les fonctions anti-inflammatoires de S100A8 sont principalement extra cellulaires. En comparant les souris déficientes pour S100a8 et S100a9, nous avons étudié le rôle de S100A8 et S100A9 dans le psoriasis induit par l’imiquimod chez la souris. Dans ce modèle, S100A8 et S100A9 amoindrissent l’hyperplasie et l’inflammation de la peau. Ces travaux ont montré que S100A8 contrôle la différenciation et la prolifération des kératinocytes. Aussi, S100A8 et S100A9 contrôlent l’infiltration de neutrophiles dans le derme ainsi que la réponse des lymphocytes T producteurs d’IL-17 dans les ganglions lymphatiques et le derme.Les travaux de cette thèse démontrent que S100A8 est anti-inflammatoire dans l’arthrite et le psoriasis, mais que S100A9 possède des fonctions différentes dans l’inflammation dépendamment du type de réaction inflammatoire. Par ailleurs, nous avons révélé que deux alarmines peuvent étonnamment exercer des fonctions anti-inflammatoires. La compréhension de ces nouveaux rôles de modulation de l’inflammation pourrait contribuer au développement de nouvelles thérapies.
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10

Endoh, Yasumi Medical Sciences Faculty of Medicine UNSW. "New mechanisms modulating S100A8 gene expression." Publisher:University of New South Wales. Medical Sciences, 2008. http://handle.unsw.edu.au/1959.4/42942.

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S100A8 is a highly-expressed calcium-binding protein in neutrophils and activated macrophages, and has proposed roles in myeloid cell differentiation and host defense. Functions of S100A8 are not fully understood, partly because of difficulties in generating S100A8 knockout mice. Attempts to silence S100A8 gene expression in activated macrophages and fibroblasts using RNA interference (RNAi) technology were unsuccessful. Despite establishing validated small interfering RNA (siRNA) systems, enzymaticallysynthesized siRNA targeted to S100A8 suppressed mRNA levels by only 40% in fibroblasts activated with FGF-2+heparin, whereas chemically-synthesized siRNAs suppressed S100A8 driven by an S100A8-expression vector by ~75% in fibroblasts. Suppression of the gene in activated macrophages/fibroblasts was low, and some enzymatically-synthesized siRNAs to S100A8, and unrelated siRNA to GAPDH, induced/enhanced S100A8 expression in macrophages. This indicated that S100A8 may be upregulated by type-1 interferon (IFN). IFN-β enhanced expression, but did not directly induce S100A8. Poly (I:C), a synthetic dsRNA, directly induced S100A8 through IL-10 and IFN-dependent pathways. Induction by dsRNA was dependent on RNA-dependent protein kinase (PKR), but not cyclooxygenase-2, suggesting divergent pathways in LPS- and dsRNA-induced responses. New mechanisms of S100A8 gene regulation are presented, that suggest functions in anti-viral defense. S100A8 expression was confirmed in lungs from influenza virus-infected mice and from a patient with severe acute respiratory syndrome (SARS). Multiple pathways via mitochondria mediated S100A8 induction in LPS-activated macrophages; Generation of reactive oxygen species via the mitochondrial electron transport chain and de novo synthesis of ATP may be involved. This pathway also regulated IL-10 production, possibly via PKR. Extracellular ATP and its metabolites enhanced S100A8 induction. Results support involvement of cell stress, such as transfection, in S100A8 expression. A breast tumor cell line (MCF-7) in which the S100A8 gene was silenced, was established using micro RNA technology; S100A8 induction by oncostatin M was reduced by >90% in stably-transfected cells. This did not alter MCF-7 growth. The new approach to investigate the role of S100A8 in a human tumor cell line may assist in exploring its functions and lead to new studies concerning its role in cancer.
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11

Mondet, Julie. "Impacts cliniques et physiopathologiques de l'équilibre redox et de la protéine S100A8 extracellulaire dans les leucémies aiguës myéloïdes de novo de l'adulte (hors LAM3)." Thesis, Université Grenoble Alpes (ComUE), 2018. http://www.theses.fr/2018GREAS007/document.

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Les leucémies aigues myéloïdes (LAM) sont caractérisées par une expansion clonale de cellule(s) souche(s) leucémique(s) bloquée à un stade précoce de maturation. Malgré les avancées thérapeutiques, leur pronostic reste sombre et des progrès thérapeutiques doivent encore être réalisés. Dans les LAM, les espèces réactives de l’oxygène (ROS) sont considérées comme, d’une part, participant à la leucémogenèse et, d’autre part, comme hautement impliquées dans la sensibilité aux chimiothérapies conventionnelles. Par ailleurs, l’équilibre redox qui participe aux dérégulations métaboliques associées au processus leucémique, dépend de nombreux régulateurs, dont la protéine S100A8, protéine connue pour son action stimulatrice sur la NADPH oxydase et sa valeur pronostique dans les LAM.Ce travail s’est donc intéressé à la caractérisation des désordres oxydatifs dans les LAM afin d’évaluer leur impact clinico-biologique, et d’autre part au rôle de la sécrétion de la S100A8 dans le microenvironnement médullaire. De plus, à partir de lignées leucémiques, nous avons étudié l’impact de la S100A8 exogène sur la production de ROS, la respiration mitochondriale et le métabolome des cellules blastiques.A partir d’une cohorte de 84 patients atteints de LAM de novo au diagnostic, nous avons mis en évidence des désordres de l’équilibre redox à la fois dans les cellules leucémiques, dans les cellules normales de l’environnement médullaire ainsi que sur les systèmes régulateurs antioxydants (SOD, GPX, glutathion…). De plus, nous avons montré que la production des ROS observée en réponse à des modulateurs de la mitochondrie, qui reflète indirectement la fonctionnalité mitochondriale, joue un rôle pronostique indépendant des facteurs pronostiques habituels. L’analyse de la S100A8 dans les plasmas médullaires montre une expression augmentée dans les LAM, d’origine monocytaire majoritairement et est associée à des anomalies moléculaires de bon pronostic (inv(16), NPM1) ou un sous-groupe de patients FLT3-ITD mutés présentant une meilleure survie. Enfin, l’étude de la S100A8 sur les lignées leucémiques a permis de mettre en évidence la diversité de ses effets sur la croissance cellulaire, l’apoptose, la production de ROS ainsi qu’une variation métabolique de la phosphocholine dont les mécanismes restent à explorer.En conclusion, mon travail apporte des éléments originaux sur les particularités de l’équilibre bio-énergétique dans les LAM. Il souligne, que l’impact de ses dérégulations sur le pronostic des patients résulte de la combinaison d’un ensemble de facteurs métaboliques, qui doivent être appréhender dans leur globalité pour une meilleure efficacité thérapeutique
Acute myeloid leukemia (AML) is characterized by clonal expansion of leukemic(s) cell(s) blocked at an early stage of maturation. Despite therapeutic advances, their prognosis remains poor and therapeutic improvements are needed. In AML, reactive oxygen species (ROS) are considered to contribute to leukemogenesis and, on the opposite, standard chemotherapies exert cytotoxicity via ROS. In addition, the redox balance acts on metabolic dysregulation in AML and depends on many regulators, such as S100A8 protein, associated with worst prognostic in AML and known to stimulate NADPH oxidase.In this context, this work focuses on oxidative disorders, and S100A8 expression in bone marrow microenvironment according to clinical-biological characteristics and evaluate their prognostic impact in AML. In addition, we investigated the impact of exogenous S100A8 on ROS production, mitochondrial respiration, and metabolism in leukemia cell lines.In a cohort of 84 de novo AML at diagnosis, we demonstrate the existence of redox balance disorders on leukemic cells, on normal cells from bone marrow microenvironment, and on antioxidant systems (SOD, GPX, glutathione ...). In addition, ROS production observed in response to mitochondrial modulators indirectly reflects mitochondrial functionality plays a prognostic role independent of the current prognostic factors. The analysis of S100A8 in bone marrow plasmas shows a higher expression in AML than in healthy controls or other hematological neoplasms. This hyperexpression is predominantly of monocytic origin and is associated with molecular abnormalities of good prognosis such as (inv (16), NPM1) or with a subgroup of mutated FLT3-ITD patients with better survival. Finally, the study of S100A8 on leukemia cell lines highlights its heterogeneous effect on cell growth, apoptosis, ROS production and on NOX regulation. Furthermore, we observe a S100A8-phosphocholine change which remains to be explored.In conclusion, this work provides original information on bio-energetic balance in AML and their prognostic impacts, emphasizing that these metabolic alterations impact AML prognosis through complex interactions
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Dubois, Christelle. "Confirmation de biomarqueurs pour le pronostic du sepsis et développement de tests rapides High plasma level of S100A8/S100A9 and S100A12 at admission indicates a higher risk of death in septic shock patients Top-down and bottom-up proteomics of circulating S100A8/S100A9 complexes in plasma of septic shock patients." Thesis, Université Paris-Saclay (ComUE), 2019. http://www.theses.fr/2019SACLS521.

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Le sepsis est la 3eme cause de mortalité dans les pays occidentaux, avec un taux de mortalité entre 20 et 50% selon la sévérité. La « prédiction » du devenir clinique du patient est essentielle pour établir le traitement le plus adéquat. Quelques protéines marqueurs de l'inflammation ou d'une infection (CRP, procalcitonine) sont citées pour le suivi des patients en clinique mais manquent de spécificité pour le sepsis. D'autre part, les études « omiques » ont permis de générer des listes de biomarqueurs potentiels du pronostic vital du sepsis. En revanche, aucun n'a encore été validé et/ou confirmé en fonction de la gravité du sepsis et du devenir du patient. Il faut pour cela accéder non seulement à des cohortes de patients parfaitement caractérisées et également disposer de méthodes quantitatives robustes et validées. La spectrométrie de masse apporte une capacité de spécificité et de multiplexage à haut niveau qui permettait de confirmer l'intérêt d'une ou plusieurs de ces protéines dans le cas du pronostic du sepsis. Les dosages immunologiques apportent quant à eux en plus de la sensibilité et de la spécificité, une mise en œuvre en routine clinique simple et rapide. Dans un premier temps, une liste de biomarqueurs identifiés avec des cohortes de patients a été établie d’après la littérature. Puis, des méthodes de quantification de ces biomarqueurs ont été développées. Nous nous sommes intéressés d’une part à quantifier les calgranulines dans le plasma en développant des ELISA et des méthodes de spectrométrie de masse par des approches bottom-up et top-down. D’autre part, deux méthodes de quantification multiplexes ont été développées par spectrométrie de masse avec et sans étape d’immunopurification en fonction des concentrations des protéines présentes dans le plasma afin de vérifier la pertinence de la liste de biomarqueurs potentiels. Toutes ces méthodes ont été appliquées à une cohorte de 49 patients atteints de choc septique
Sepsis is the 3rd leading cause of death in Western countries, with a mortality rate between 20 and 50% depending on the severity. The 'prediction' of the patient's clinical outcome is essential to establish the most appropriate treatment. Some inflammation or infection markers protein (CRP, procalcitonin) are cited for clinical follow-up of patients but lack specificity for sepsis. On the other hand, "omics" studies have generated lists of potential biomarkers of sepsis prognosis. However, none have yet been validated and/or confirmed based on the severity of the sepsis and the patient's fate. This requires access not only to fully characterized patient cohorts but also to robust and validated quantitative methods. Mass spectrometry provides a high level of specificity and high multiplex capacity and that would allow to confirm the interest of one or more of these proteins for sepsis prognosis. Immunological assays provide, in addition to sensitivity and specificity, a simple and rapid routine clinical implementation. First, a list of biomarkers identified with patient cohorts was established from the literature. Then, methods to quantify these candidate biomarkers were developed. On the one hand, we have been interested in quantifying calgranulins in plasma by developing ELISAs and mass spectrometry methods using bottom-up and top-down approaches. On the other hand, two multiplex quantification methods by mass spectrometry with and without immunopurification step according to protein concentrations have been developed to verify the relevance of the list of potential biomarkers. All these methods were applied to a cohort of 49 patients with septic shock
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13

Okada, Kouki. "CD68 on rat macrophages binds tightly to S100A8 and S100A9 and helps to regulate the cells’ immune functions." 京都大学 (Kyoto University), 2017. http://hdl.handle.net/2433/225517.

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14

Chapeton, Montes Julie Andrea. "Caractérisation des voies alternatives de sécrétion des protéines S100A8/A9 et S100A12 par les neutrophiles humains." Master's thesis, Université Laval, 2015. http://hdl.handle.net/20.500.11794/26156.

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Bien que les protéines S100A8/A9 et S100A12 exprimées par les neutrophiles ne possèdent pas de peptide signal, elles sont retrouvées dans le sérum de patients souffrant de diverses maladies inflammatoires. Les mécanismes de sécrétion de ces protéines demeurent peu connus ainsi que les agonistes qui favorisent leur sécrétion. Nous avons donc émis l´hypothèse que plusieurs voies de sécrétion alternative ainsi que plusieurs agonistes des neutrophiles pourraient participer à la libération de ces protéines. Dans un premier temps, nous avons étudié les stimuli capables de provoquer la sécrétion de la calprotectine et/ou de la S100A12. Dans une deuxième partie, nous nous sommes intéressés aux signaux et mécanismes alternatifs de sécrétion impliqués dans le relargage de ces protéines. L’ensemble de ces travaux montre la complexité des voies de sécrétion alternatives impliquées dans la sécrétion des protéines S100 et comment ces voies sont influencées par l’activation des neutrophiles par différents agonistes.
Although S100A8/A9 (calprotectin) and S100A12 proteins expressed by neutrophils lack a signal peptide, they are found in the serum of patients with various inflammatory diseases. However, the mechanisms of secretion and the agonists that promote their secretion are still unknown. We hypothesized that several alternative secretory pathways and several agonists of neutrophils may participate in the release of S100A8/A9 and S100A12 protein. Initially, we studied the stimuli inducing the secretion of calprotectin and / or S100A12. In a second part, we were interested in signals and alternative mechanisms of secretion involved in the release of the calprotectin and S100A12. In conclusion, this study shows the complexity of alternative secretion pathways involved in S100 secretion and that these pathways are influenced by the activation of neutrophils by various agonists.
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Wache, Christina. "Rolle von S100A8/A9 in der Immunpathogenese der Pneumokokkenmeningitis." Diss., Ludwig-Maximilians-Universität München, 2015. http://nbn-resolving.de/urn:nbn:de:bvb:19-179585.

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Baillet, Athan. "Régulation de l'activité de la NADPH oxydase des neutrophiles par des enzymes du métabolisme du glucose et l'hétérocomplexe S100A8/S100A9 : application à la polyarthrite rhumatoïde." Phd thesis, Université de Grenoble, 2011. http://tel.archives-ouvertes.fr/tel-00680093.

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La Polyarthrite Rhumatoïde est caractérisée par une synovite à l'origine de lésions progressives ostéo-articulaires induites par les formes réactives de l'oxygène (ROS) produites par la NADPH oxydase des polynucléaires neutrophiles (PMN). La NADPH oxydase des phagocytes, est formée d'un centre catalytique membranaire, le cytochrome b558, sur lequel vient s'associer des protéines cytosoliques régulatrices (p67phox, p47phox, p40phox et Rac1/2). Nous avons étudié la spécificité de l'interaction entre la (6-phosphofructokinase 2) et de la 6PGDH (6-phosphogluconate déshydrogénase) et la NADPH oxydase des PMN. D'autre part, nous avons caractérisé les domaines de l'hétérocomplexe S100A8/A9 impliqués dans l'activation de la NADPH oxydase phagocytaire. Par ailleurs, une étude de la signature protéique dans le liquide synovial a été menée afin de rechercher l'empreinte de l'activation du PMN dans la PR.Après stimulation par le PMA, la 6PGDH et la PFK2 co-imunoprécipitent avec les facteurs cytosoliques p67phox, p47phox and p40phox. Les expériences de microscopie confocale suggèrent une co-localisation de ces deux enzymes du métabolisme du glucose avec la NADPH oxydase, dans des micro-domaines membranaires : les radeaux lipidiques. La 6PGDH est impliquée dans l'activation de la NADPH oxydase phagocytaire en élevant la concentration du NADPH cytosolique mais également en augmentant l'affinité de cette enzyme pour son substrat, le NADPH. PFK2 est l'enzyme majeure de la régulation de la glycolyse, voie est essentielle pour la production d'ATP du PMN. L'utilisation du complexe S100A8/A9 et de protéines chimères de fusion nous a permis de révéler que la partie C-terminale de S100A8 est impliquée dans la liaison avec le cytochrome b558 et l'activation de la NADPH oxydase phagocytaire. In vivo, le profil protéique du liquide articulaire de PR a révélé l'empreinte de l'activation du PMN dans cette pathologie avec une surexpression des protéines S100A8 et S100A9. Une production ectopique de S100A8/A9 par les synoviocytes de type fibroblastique a été mise en évidence.En conclusion, la 6PGDH, la PFK2 et l'hétérodimère S100A8/A9 sont de nouveaux partenaires d'activation de la NADPH oxydase des phagocytes. Dans la PR, l'activation des PMNs conduit à la sécrétion de S100A8/A9 qui semblent constituer à la fois des biomarqueurs pertinents, mais également des cibles thérapeutiques potentielles.
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Eggers, Kai. "S100A8-S100A9 abhängige Akivierung der RAGE-MAPK-NF-kB-Signaltransduktionssequenz [RAGE-MAPK-NF-kappa-B-Signaltransduktionssequenz] ein neues Modell der chronischen Inflammation am humanen Endothel /." [S.l.] : [s.n.], 2003. http://deposit.ddb.de/cgi-bin/dokserv?idn=974453455.

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Wache, Christina [Verfasser], and Uwe [Akademischer Betreuer] Ködel. "Rolle von S100A8/A9 in der Immunpathogenese der Pneumokokkenmeningitis / Christina Wache. Betreuer: Uwe Ködel." München : Universitätsbibliothek der Ludwig-Maximilians-Universität, 2015. http://d-nb.info/1067752447/34.

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19

Bouzidi, Farid. "Rôle de l'hétérodimère S100A8/A9 dans la régulation de l'activité NADPH oxydase des neutrophiles." Université Joseph Fourier (Grenoble), 2002. http://www.theses.fr/2002GRE10127.

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20

Taubert, Teodora [Verfasser]. "S100A8/A9-Charakterisierung eines neuen inflammatorischen Markers in der koronaren Herzerkrankung / Teodora Taubert, geb. Ioanovici." Berlin : Medizinische Fakultät Charité - Universitätsmedizin Berlin, 2012. http://d-nb.info/1026694809/34.

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21

Pepper, R. J. "The role of calprotectin (S100A8/A9) in the pathogenesis of glomerulonephritis and ANCA-associated vasculitis." Thesis, University College London (University of London), 2013. http://discovery.ucl.ac.uk/1400216/.

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Glomerulonephritis is a common cause of end-stage renal failure and a feature of ANCA-associated vasculitis (AAV). AAV is an example of a small vessel vasculitis, characterised by inflammation of the endothelium and glomeruli in which the interaction between leukocytes and endothelial cells play a crucial role. Macrophages have been demonstrated to have a critical role during the initiation and progression of glomerulonephritis. Calprotectin (also termed S100A8/A9, mrp8/14), is a complex of 2 small calcium binding proteins that is abundantly expressed in neutrophils and monocytes as well as early infiltrating macrophages and is a ligand of Toll-like receptor 4 (TLR4) and the receptor for advanced glycation end-products (RAGE). There is growing evidence in animal models and patients with autoimmune diseases, of calprotectin being involved in the inflammatory response, as well as being a marker of activation of innate immunity. I have initially characterised the presence of calprotectin-positive cells in renal biopsies of patients with focal and crescentic AAV glomerulonephritis, therefore linking the presence of these cells with renal outcome. Patients with active AAV have elevated serum calprotectin levels, as well as significant expression on neutrophils and monocytes, which although decrease during remission, does not normalise. I have demonstrated that mrp14-/- mice are protected from nephrotoxic nephritis, which is abrogated by use of LPS during disease progression. Bone-marrow derived macrophages (BMDMs) release pro-inflammatory cytokines following stimulation with calprotectin; mediated by TLR4. Mrp14-/- BMDMs do not respond to the pro-inflammatory stimulus of S100A8/A9. The co-culture of endothelial cells (EC) and wild-type BMDMs is pro-inflammatory unlike that of mrp14-/- BMDM and ECs. Mrp14-/- mesangial cells also have a decreased pro-inflammatory response. This work demonstrates that calprotectin has a role in experimental glomerulonephritis as well as AAV patients. This may improve our understanding of the inflammatory response and identify a new novel treatment targets.
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Müller, Irene [Verfasser], Carsten [Akademischer Betreuer] Tschöpe, Sophie Van [Akademischer Betreuer] Linthout, Jens [Gutachter] Kurreck, Roland [Gutachter] Lauster, Carsten [Gutachter] Tschöpe, and Sophie Van [Gutachter] Linthout. "Role of NOD2 and S100A8/S100A9 in the pathogenesis of Coxsackievirus B3-induced myocarditis / Irene Müller ; Gutachter: Jens Kurreck, Roland Lauster, Carsten Tschöpe, Sophie Van Linthout ; Carsten Tschöpe, Sophie Van Linthout." Berlin : Technische Universität Berlin, 2017. http://d-nb.info/1156013542/34.

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23

Endoh, Ikuko Medical Sciences Faculty of Medicine UNSW. "New mechanisms of regulation of mast cell activation." Publisher:University of New South Wales. Medical Sciences, 2008. http://handle.unsw.edu.au/1959.4/42937.

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Mast cells (MCs) play a central role in inflammation by releasing mediators following activation. S100A8 and S100A9 are abundantly expressed in inflammatory sites such as asthmatic lung, sunburnt skin and atherosclerosis where MCs are involved in pathogenesis; roles of S100A8 in MC function are undetermined. The aims of this thesis were to determine effects of S100A8 on MC activation, particularly provoked by IgE and UVB. Initially, effects of UVB on MC activation were investigated as detailed functions were unclear. Cord blood-derived human mast cells (CBMCs) were treated in vitro with varying doses of UVB and production of multiple cytokines and viability investigated. UVB exposure selectively increased levels of IL-8 (CXCL8), and to a less extent IL-1β, but not eight other cytokines tested. New protein synthesis partially contributed and IL-8 production was p38 MAPK-dependent. UVB dose-dependently induced MC apoptosis indicating a potential regulatory mechanism of MC function. The ability of recombinant S100A8, S100A9 or S100A8/9 heterodimer to modulate IgE/antigen (DNP/anti-DNP)-mediated activation of a murine MC line, and of bone marrow-derived (mBM) MC activation was determined. The S100s did not directly induce degranulation or induce IL-6. S100A8 significantly inhibited DNP/anti-DNP-provoked degranulation, and IL-6 and TNF mRNA and protein induction. S100A8 did not alter FcεRIα expression. S100A9 was less effective; and the S100A8/9 complex was also suppressive. S100A8 only weakly suppressed non-specific MC degranulation. Mutation of Cys41 in S100A8 negated its suppressive activity. Because S100A8 scavenges oxidants via this reactive Cys residue, we propose that this may mediate its ability to downmodulate IgE-dependent MC responses. Similar to the thiol scavenger N-acetyl-L-cysteine, S100A8 but not the Ala41 mutant, attenuated DNP/anti-DNP-provoked LAT phosphorylation. However, the disulfide-bonded S100A8 dimer and S100A8 containing a sulfinamide bond between Cys41 and Lys34/35 also reduced MC activation, indicating an additional pathway(s). S100A8 did not suppress antigen/IgE-induced responses of CBMC possibly because these may not truly reflect fullymature human tissue MCs. S100A8 did not alter UVB-induced IL-8 release by CBMCs, or affect apoptosis. Murine S100A8 may have anti-inflammatory properties by regulating MC activation in an activator-specific manner, at least partially by scavenging ROS to suppress intracellular signalling.
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Kahlert, Andreas Joachim [Verfasser], and Karin [Akademischer Betreuer] Hengst. "Die Funktion der calciumbindenden Proteine S100A8/A9 in der Dissoziation epithelialer Zell-Zell-Kontakte / Andreas Joachim Kahlert. Betreuer: Karin Hengst." Münster : Universitäts- und Landesbibliothek der Westfälischen Wilhelms-Universität, 2012. http://d-nb.info/1027027806/34.

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25

Eisenblaetter, Michel. "Visualisation and monitoring of tumour-mediated immune modulation in primary cancer and premetastatic niche establishment using S100A8/A9-specific imaging." Thesis, King's College London (University of London), 2017. https://kclpure.kcl.ac.uk/portal/en/theses/visualisation-and-monitoring-of-tumourmediated-immune-modulation-in-primary-cancer-and-premetastatic-niche-establishment-using-s100a8a9specific-imaging(870ae544-5148-4fd8-a1af-bbaa01198b9d).html.

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Development and spread of malignant disease are crucially dependent on the recruitment and reprogramming of various immune cells. At the primary tumour site, tumour-associated macrophages and immature myeloid cells facilitate local invasion and neoangiogenesis and promote the establishment of a tumour-permissive microenvironment. Systemic cancer spread is preceded by the establishment of a permissive microenvironment in the target tissue of metastasis – the premetastatic niche. As crucial players in the establishment of the premetastatic niche as well as the orchestration of tumour immune evasion at primary tumour level, myeloid-derived suppressor cells (MDSC) release S100A8/A9, an exosomal protein that contributes to metastasis, angiogenesis, and immune suppression. S100A8/A9 is a ligand for TLR4 and RAGE and acts as a chemo-attractant to myeloid cells. The local S100A8/A9 level is a sensitive indicator of immune cell activity. Building on the development of S100A8/A9-specific optical imaging for monitoring of local inflammation, I assessed S100A8/A9 imaging for the visualisation of tumourassociated immune cell activity. I strived to establish local S100A8/A9 imaging signals to be coincident with the increased activity of tumour-promoting immune cells and therefore indicative of high malignant activity within the primary tumour and the establishment of a premetastatic niche in distant tissue. A S100A9-targeting antibody has been labelled for optical in vivo imaging and used for fluorescence imaging of tumour-associated inflammation in an orthotopic murine breast cancer model. The local S100A9-signal could be shown to reflect the tumourassociated macrophage and MDSC abundance and activity and predict local tumour growth. To enable systemic imaging of tumour-mediated immune cell activity, the optical tracer has been developed into a SPECT tracer for labelling with 111In and tested in a well-characterised murine model of local inflammation. In a syngeneic mouse model of metastatic breast cancer, S100A8/A9-SPECT sensitively reflected MDSC abundance and the establishment of an immunosuppressive environment in premetastatic lung tissue. A significant correlation between the S100A8/A9 imaging signal in the premetastatic lung and the subsequent metastatic tumour burden could be established. The results suggest S100A8/A9 as a potent imaging biomarker for monocyte activity, reflective of tumour-associated immune cell activity.
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Yanamandra, Kiran. "Studies of in vivo prostate amyloidosis and autoimmune responses towards amyloid structures in neurodegeneration." Doctoral thesis, Umeå universitet, Institutionen för medicinsk kemi och biofysik, 2010. http://urn.kb.se/resolve?urn=urn:nbn:se:umu:diva-37561.

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By using multidisciplinary analysis of CA inclusions in prostate glands of patients diagnosed with prostate cancer, we have revealed that their major components are the amyloid forms of S100A8 and S100A9 proteins associated with numerous inflammatory conditions and types of cancer. We have demonstrated that material closely resembling CA can be produced from S100A8/A9 in vitro and shows the characters of amyloids. This process is facilitated by calcium or zinc, both of which are abundant in ex vivo inclusions. These observations were supported by computational analysis of the S100A8/A9 calcium-dependent aggregation propensity profiles. We have found DNA and proteins from Escherichia coli in CA bodies, suggesting that their formation is likely to be associated with bacterial infection. CA inclusions were also accompanied by the activation of macrophages and by an increase in the concentration of S100A8/A9 in the surrounding tissues, indicating inflammatory reactions. These findings, taken together, suggest a link between bacterial infection, inflammation and amyloid deposition of pro-inflammatory proteins S100A8/A9 in the prostate gland, such that a self-perpetuating cycle can be triggered and may increase the risk of malignancy in the ageing prostate. We evaluated the autoimmune reactions to endocrine (insulin) and astrocytical (S100B) biomarkers in the blood sera of PD patients compared with healthy controls. Peripheral immune responses can be sensitive indicators of disease pathology. We found a statistically significant increase of the autoimmune responses to both antigens in patients compared with controls. Heterogeneity of the immune responses observed in patients may reflect the modulating effect of multiple variables associated with neurodegeneration and also changes in the basic mechanisms of individual autoimmune reactivity. We did not detect any pronounced immune reactions towards insulin amyloid fibrils and oligomers in patients, indicating that an amyloid-specific conformational epitope is not involved in immune recognition of this amyloid type. Immune reactions towards S100B and insulin may reflect the neurodegenerative brain damaging processes and impaired insulin homeostasis occurring in PD. Generated auto-antibodies towards the major amyloidogenic protein involved in PD Lewy bodies - a-synuclein and its amyloid oligomers and fibrils were measured in the blood sera of early and late PD patients and controls by using ELISA, Western blot and Biacore surface plasmon resonance analyses. We found significantly higher antibody levels towards monomeric a-synuclein in the blood sera of PD patients compared to controls, though the responses decreased with PD progression. There were no noticeable immune responses towards amyloid oligomers, but substantially increased levels of IgGs towards a-synuclein amyloid fibrils both in PD patients and controls, which subsided with the disease progression. Pooled IgGs from PD patients and controls interacted also with amyloid fibrils of Ab (1-40) and hen lysozyme, however the latter were recognized with lower affinity. This suggests that IgGs bind to amyloid conformational epitope, though displaying higher specificity towards human amyloid species associated with neurodegeneration. The findings suggest the protective role of autoimmunity in PD and therefore immune reactions towards PD major amyloid protein - a-synuclein can be used in treatment strategies and in diagnostics, especially in identifying early disease.
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Zwicker, Stephanie. "Psoriasin (S100A7) and koebnerisin (S100A15) in the model of inflammation." Diss., Ludwig-Maximilians-Universität München, 2014. http://nbn-resolving.de/urn:nbn:de:bvb:19-185702.

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28

Erben, Till [Verfasser]. "Detektion der S100A8/A9 Proteine und des Reg3A Proteins bei entzündlichen und neoplastischen Erkrankungen des Pankreas in Gewebe-, Zellkultur- und Blutproben / Till Erben." Hannover : Bibliothek der Tierärztlichen Hochschule Hannover, 2013. http://d-nb.info/1037798899/34.

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Belot, Nathalie. "Caractérisation du rôle des protéines S100A4 et S100A6 dans la migration de cellules gliales tumorales." Doctoral thesis, Universite Libre de Bruxelles, 2004. http://hdl.handle.net/2013/ULB-DIPOT:oai:dipot.ulb.ac.be:2013/211198.

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Baillet, Athan. "Régulation de l'activité de la NADPH oxydase des neutrophiles par des enzymes du métabolisme du glucose et l'hétérocomplexe S100A8/A9 Application à l'étude de la Polyarthrite Rhumatoïde." Phd thesis, Université de Grenoble, 2011. http://tel.archives-ouvertes.fr/tel-00654815.

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La Polyarthrite Rhumatoïde, caractérisée par une synovite à l'origine de lésions progressives ostéo-articulaires, est le plus fréquent des rhumatismes inflammatoires. Les formes réactives de l'oxygène (ROS) produites par la NADPH oxydase des polynucléaires neutrophiles (PMN) infiltrant le pannus rhumatoïde, sont responsables de lésions tissulaires. La NADPH oxydase des phagocytes, est formée d'un centre catalytique membranaire, le cytochrome b558, sur lequel vient s'associer des protéines cytosoliques régulatrices (p67phox, p47phox, p40phox et Rac1/2). L'étude du complexe NADPH oxydase isolé et constitutivement actif, à partir de PMN activés, a révélé la présence de deux enzymes impliquées dans la régulation du métabolisme du glucose. Il s'agit de la PFK2 (6-phosphofructokinase 2) et de la 6PGDH (6-phosphogluconate déshydrogénase) [Paclet et al. 2007]. De plus, l'étude des protéines cytosoliques retenues sur une matrice d'affinité ciblant p47phox, a établi que les protéines S100A8 et S100A9, constituant 40% des protéines cytosoliques du PMN, participent à l'activation de l'oxydase [Berthier et al. 2003]. L'hétérocomplexe S100A8/A9, augmente l'activité de la NADPH oxydase phagocytaire et induit un changement conformationnel du cytochrome b558. Au regard de l'importance de la stimulation du PMN dans la physiopathologie de la PR, notre objectif, à terme, est d'analyser les mécanismes de l'activation de la NADPH oxydase dans cette pathologie. D'une part, nous avons étudié la spécificité de l'interaction entre la 6PGDH ou la PFK2 et la NADPH oxydase des PMN. D'autre part, nous avons caractérisé les domaines de l'hétérocomplexe S100A8/A9 impliqués dans l'activation de la NADPH oxydase phagocytaire. Par ailleurs, une étude de la signature protéique dans le liquide synovial a été menée afin de rechercher l'empreinte de l'activation du PMN dans la PR et de caractériser des biomarqueurs spécifiques de cette pathologie. Après stimulation par le PMA, la 6PGDH et la PFK2 co-imunoprécipitent avec les facteurs cytosoliques p67phox, p47phox and p40phox. Les expériences de microscopie confocale suggèrent une co-localisation de ces deux enzymes du métabolisme du glucose avec la NADPH oxydase, dans des micro-domaines membranaires : les radeaux lipidiques. La 6PGDH est impliquée dans l'activation de la NADPH oxydase phagocytaire en élevant la concentration du NADPH cytosolique mais également en augmentant l'affinité de cette enzyme pour son substrat, le NADPH. PFK2 est l'enzyme majeure de la régulation de la glycolyse. Dans les neutrophiles, cette voie est essentielle pour la production d'ATP disponible, d'une part, pour la phosphorylation des facteurs cytosoliques de la NADPH oxydase et d'autre part, pour la NDP Kinase. Cette dernière enzyme pourrait, secondairement, activer Rac en formant du GTP à partir d'ATP. Les protéines S100A8/A9 sont directement impliquées dans les mécanismes de régulation de la NADPH oxydase. L'utilisation du complexe S100A8/A9 et de protéines chimères de fusion nous a permis de révéler que la partie C-terminale de S100A8 est impliquée dans la liaison avec le cytochrome b558 et l'activation de la NADPH oxydase phagocytaire. In vivo, le profil protéique du liquide articulaire de PR a mis en évidence l'empreinte de l'activation du PMN dans cette pathologie. Les protéines S100A8, S100A9 permettraient de différencier le liquide synovial rhumatoïde de celui de patients arthrosiques ou souffrant d'arthrites non rhumatoïdes. De manière intéressante, une production ectopique de S100A8/A9 par les synoviocytes de type fibroblastique a été mise en évidence, suggérant une implication potentielle de ces protéines dans la physiopathologie de la PR. En conclusion, la 6PGDH, la PFK2 et l'hétérodimère S100A8/A9 sont de nouveaux partenaires d'activation de la NADPH oxydase des phagocytes. Dans la Polyathrite Rhumatoïde, l'activation des PMNs conduit à la sécrétion de S100A8/A9 qui semblent constituer à la fois des biomarqueurs pertinents, mais également des cibles thérapeutiques potentielles.
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Wehder, Liane [Verfasser], Ferdinand von [Akademischer Betreuer] Eggeling, Stephan [Akademischer Betreuer] Diekmann, and Jens [Akademischer Betreuer] Habermann. "Molekulares Imaging (MALDI-IMS) humaner Kopf-Hals-Tumore und funktionelle Analyse pathologisch exprimierter Proteine am Beispiel von S100A8 und Annexin A5 / Liane Wehder. Gutachter: Ferdinand von Eggeling ; Stephan Diekmann ; Jens Habermann." Jena : Thüringer Universitäts- und Landesbibliothek Jena, 2014. http://d-nb.info/1046563386/34.

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Goyette, Jesse Davis Medical Sciences Faculty of Medicine UNSW. "The extracellular functions of S100A12." Publisher:University of New South Wales. Medical Sciences, 2008. http://handle.unsw.edu.au/1959.4/41302.

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The S100s comprise a group of Ca2+-binding proteins of the EF-hand superfamily with varied functions. Within this family, three inflammatory-related proteins - S100A8, S100A9 and S100A12 - form a subcluster known as the 'calgranulins'. S100A12 levels are elevated in sera from patients with inflammatory diseases, such as rheumatoid arthritis and inflammatory bowel disease. S100A12 is constitutively expressed in neutrophils and induced in monocytes by LPS and TNFα, and in macrophages by IL-6. S100A12 is a potent monocyte and mast cell chemoattractant and its potentiation of mast cell activation by IgE cross-linking indicates an important role in allergic inflammation. Importantly, mast cell-dependent activation of acute inflammatory responses and monocyte recruitment is provoked by S100A12 administration in vivo. S100A12 may also influence adhesion molecule expression on endothelial cells, stimulate IL 1β and TNFinduced in monocytes production in BV 2 microglial cells, and stimulate IL 2 secretion by T lymphocytes via ligation of the receptor for advanced glycation end-products (RAGE). To date, the only extracellular receptor characterised for S100A12 is RAGE, although additional/alternate receptors are indicated. In particular, recent studies indicate that chemotaxis and mast cell activation by S100A12 are likely mediated by other receptors. The studies presented here investigated some extracellular functions of S100A12, factors influencing these functions and suggest mechanisms that may be involved. In addition to Ca2+, S100A12 binds Zn2+. Chapter 3 explores the relevance Zn2+ binding to S100A12 structure and function. Zn2+ induced formation of complexes, principally hexamers, and this was not influenced by Ca2+. S100A12 inhibited the gelatinolytic activities of matrix metalloproteinase (MMP)-2 and 9 by chelating Zn2+ from their active sites. MMPs are important in processes leading to plaque rupture. An antibody that specifically recognised Zn2+-induced complexes was generated and immunohistochemical studies demonstrated S100A12, the hexameric complex, and MMP 2 and 9 co-localisation in human atheroma. These results suggest that hexameric S100A12 may form in vivo and may implicate S100A12 in regulating plaque rupture by inhibiting MMP activity. Interestingly S100A12 synergised with LPS to induce MMP 3 and 13 expression in vitamin D3-differentiated THP 1 macrophages (THP 1 macs). S100A12 regulation of MMP expression and activity indicates that it may be involved in a self-regulatory loop, which depends on relative levels of Zn2+ and on other stimuli (eg LPS) in the inflammatory milieu. Chapter 4 describes the development of tools and methods for assessing interactions of S100A12 with cell surface receptors. To assay surface binding, an alkaline phosphatase fusion protein, a biotinylated hinge peptide and biotinylated recombinant S100A12 were generated; only S100A12 b proved useful. Surface binding of S100A12 was detected on several monocytoid/macrophage and mast cells using flow cytometry and immunocytochemistry. Some cells contained intracytoplasmic granular structures that were S100A12-positive. Unexpectedly, a subpopulation of cells in murine bone marrow-derived mast cell cultures that expressed low levels of c-kit, a marker of mature mast cells, bound high levels of S100A12. These may represent haematopoietic stem cells, which express low levels of c kit, and S100A12-mediated functional changes of these cells is worthy of characterisation. Unlike interactions of S100A8/A9 with endothelial cells, pre-incubation of S100A12 with Zn2+ or heparin had no effect on surface binding to THP 1 macs, indicating that Zn2+-induced structural changes were unlikely to alter receptor interactions. Heparan sulfate moieties are unlikely to mediate surface binding of S100A12 even though S100A12 bound heparin with relatively high affinity. Chapter 5 focussed on mechanisms involved in some S100A12 extracellular functions. Based on experiments studying effects of bovine S100A12 on BV-2 murine microglial cells, S100A12 is proposed to induce pro-inflammatory cytokine in monocytes via RAGE. Human peripheral blood mononuclear cells or human THP 1 macs activated with S100A12 did not increase cytokine induction at the mRNA or protein levels, indicating that the 'S100/RAGE pro-inflammatory axis' theory should be re-evaluated. In an attempt to provide insights into a novel receptor, mechanisms involved in S100A12-provoked THP 1 chemotaxis were investigated. This activity was sensitive to pertussis toxin, but not to an ERK1/2 pathway inhibitor, suggesting involvement of a G protein-coupled receptor. Although some RAGE ligands also bind and activate Toll-like receptors (TLRs) antibodies to TLR2 and TLR4 did not block S100A12 binding to THP 1 macs. Affinity enrichment and separation of proteins by SDS PAGE and peptide mapping by mass spectrometry identified the α and γ subunits of F1 ATP synthase, implicating ATP synthase as a putative receptor. Although primarily mitochondrial, this complex is expressed on the surface of several cell types and was confirmed on THP 1 cells and mast cells by flow cytometry. By modulating surface F1 ATP synthase activity, and thereby extracellular ATP/ADP concentrations, S100A12 may mediate its pro-inflammatory functions through G-protein coupled purinergic receptors. This work has generated new directions for studying mechanisms by which S100A12 influences monocyte/macrophage and mast cell functions that are relevant to important inflammatory diseases, such as atherosclerosis and allergic inflammation.
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Mossel, Dieuwertje M. [Verfasser], and Julia [Akademischer Betreuer] Kzhyshkowska. "Epigenetic regulation of S100A9 and S100A12 expression in monocytes-macrophage system in hyperglycemic conditions / Dieuwertje Marije Mossel ; Betreuer: Julia Kzhyshkowska." Heidelberg : Universitätsbibliothek Heidelberg, 2020. http://d-nb.info/1219303100/34.

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34

Mossel, Dieuwertje Marije [Verfasser], and Julia [Akademischer Betreuer] Kzhyshkowska. "Epigenetic regulation of S100A9 and S100A12 expression in monocytes-macrophage system in hyperglycemic conditions / Dieuwertje Marije Mossel ; Betreuer: Julia Kzhyshkowska." Heidelberg : Universitätsbibliothek Heidelberg, 2020. http://d-nb.info/1219303100/34.

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35

Turnier, Jessica L. M. D. "Urine S100 Proteins as Potential Biomarkers of Lupus Nephritis Activity." University of Cincinnati / OhioLINK, 2017. http://rave.ohiolink.edu/etdc/view?acc_num=ucin1491308278173071.

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36

Zwicker, Stephanie [Verfasser], and Ronald [Akademischer Betreuer] Wolf. "Psoriasin (S100A7) and koebnerisin (S100A15) in the model of inflammation : functional characterization in the inflammation cascade / Stephanie Zwicker. Betreuer: Ronald Wolf." München : Universitätsbibliothek der Ludwig-Maximilians-Universität, 2014. http://d-nb.info/1075456991/34.

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37

Herwig, Nadine. "Der RAGE-Ligand S100A4." Doctoral thesis, Saechsische Landesbibliothek- Staats- und Universitaetsbibliothek Dresden, 2016. http://nbn-resolving.de/urn:nbn:de:bsz:14-qucosa-214035.

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Das maligne Melanom zählt zu den aggressivsten und behandlungsresistentesten aller Krebsarten. In den letzten 20 Jahren hat sich die Rate der Melanom-Erkrankungen innerhalb der weißen Bevölkerung verdreifacht. Mittlerweile liegen eine Reihe von Untersuchungen zu den molekularbiologischen Mechanismen der Entwicklung und Progression des malignen Melanoms vor. Aktuelle Forschungsvorhaben beschäftigen sich vor allem mit der Identifizierung Melanom-spezifischer Biomarker, die diagnostische und prognostische Informationen liefern sowie die Entwicklung einer zielgerichteten, kombinierten und individualisierten Therapie des metastasierenden Melanoms ermöglichen. In diesem Kontext soll die vorliegende Arbeit einen weiteren Beitrag zum Verständnis der Metastasierungskaskade und der daran beteiligten Proteine leisten. Aufgrund der Überexpression in einer Reihe von Tumoren und seiner geringen Molmasse von lediglich 11,5 kDa bietet sich das S100A4-Protein als Marker mit hoher prognostischer Signifikanz für verschiedene Tumorentitäten an. Jedoch ist die Beteiligung von S100A4 bei der Ausbildung des invasiven Tumorphänotyps noch nicht vollständig aufgeklärt. S100A4 besitzt zahlreiche intra- und extrazelluläre Bindungspartner, wobei die Metastasierung scheinbar ausschließlich durch das extrazelluläre Protein beeinflusst wird. S100A4 wechselwirkt extrazellulär beispielsweise mit dem Rezeptor für fortgeschrittene Glykierungsendprodukte (RAGE). Ziel dieser Arbeit war es, speziell die Bedeutung von S100A4 und seiner Interaktion mit RAGE für das prometastatische Verhalten von Melanomzellen in vitro und in vivo näher zu charakterisieren. Darüber hinaus sollte die Beteiligung von S100A4 bei der Gehirn-Metastasierung untersucht werden, wobei insbesondere die Regulierung der Endothelzell-Permeabilität und der transendothelialen Migration der Melanomzellen im Vordergrund stand. Im Rahmen dieser Arbeit wurde gezeigt, dass S100A4 und die Interaktion mit RAGE die prometastatischen Eigenschaften der A375-Melanomzellen förderte. Zudem verringerte extrazelluläres S100A4 die Zell-Integrität von Gehirn-Endothelzellen und erleichterte somit die Durchdringung der Blut-Hirn-Schranke. Diese Erkenntnis lässt sich möglicherweise auf andere Blut-Gewebe-Schranken übertragen. Die In-vivo-Orientierungsstudie zeigte, dass S100A4- und RAGE-überexprimierende Zellen zu einer verstärkten disseminierten Metastasierung führten, wobei sich zwei unterschiedliche Verteilungsmuster ergaben. Darüber hinaus führten beide Zelllinien vereinzelt zur Bildung von Gehirnmetastasen, wodurch sich die intrakardiale Injektion durchaus als Modell für weitere Therapiestudien mit dem Augenmerk der S100A4-RAGE-stimulierten Metastasierung eignet. Die genauere Kenntnis regulativer Mechanismen bei der Synthese und Sekretion von S100A4 sowie die pathophysiologische Differenzierung der S100A4-Interaktion mit RAGE eröffnen neue Wege, die S100A4-vermittelten Effekte therapeutisch zu beeinflussen. Daraus lassen sich möglicherweise neue zielgerichtete Radionuklid-basierte Therapieansätze für das metastasierende Melanom ableiten.
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38

McNeill, Eileen. "Neutrophil function in S100A9 null mice." Thesis, University College London (University of London), 2006. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.423552.

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39

Raponi, Eric. "L'expression séquentielle des calciprotéines S100A1 et S100B dans les cellules gliales du système nerveux central caractérise différents stades développementaux en relation avec leurs potentialités de différenciation." Université Joseph Fourier (Grenoble), 2005. https://tel.archives-ouvertes.fr/tel-00178904.

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Les précurseurs neuraux adultes possèdent une plasticité cellulaire suggérant un role dans l'apparition de pathologies mais aussi un potentiel curratif inespéré. Cependant, l'emploi clinique de ces cellules nécessite une connaissance des mécanismes biologiques contrôlant leur prolifération, maturation ou spécification cellulaire. Dans cette thèse nous avons étudié l'expression des protéines 8100 A1 et B dans les cellules progénitrices d'oligodendrocytes (OPC) et les cellules souches astrocytaires. Nous avons démontré que 1) toutes les cellules gliales expriment précocement la 8100A1 alors que la 8100B est liée à leur maturation 2) la 8100B régule la maturation des OPC 3) les cellules souches astrocytaires adultes sont maintenues dans un stade de développement immature (8100B-) grâce à l'EGF, afin de conserver leurs propriétés germinales. Ces résultats démontrent un lien entre les protéines 8100A1/B, la maturation des cellules gliales et leurs propriétés de différenciation cellulaire
Adult neural precursors possess a cellular plasticity reflecting their possible role in disease and for treating neurological illness. However, we need to truly understand the biological mecanisms governing these cells in order to use them in futur cellular therapy. Ln this thesis, we have studied the 8100 A1 and B expression pattern both in oligodendrocyte progenitor calls and in astrocytic neural stem cells. We demonstrate that 1) ail glial cells precociously express 81 OOA 1 whereas 81 OOB appearence is only linked to their maturation step 2) 8100B is a molecular actor regulating OPC maturation 3) in adult brain, astrocytic neural stem cells are maintained in a 8100Bimmature developmental stage to preserve their potential via an EGF microenvironnemental pathway. Altogether, these results hightlight a link beetween 8100A1/B proteins, glial cells maturation and cellular plasticity
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40

Nogueira, Thiago de Oliveira. "Efeito antinociceptivo induzido pelo glicogênio em ratos submetidos ao modelo de pressão de pata: relação com a migração neutrofílica e a expressão da proteína S100A9." Universidade de São Paulo, 2011. http://www.teses.usp.br/teses/disponiveis/10/10133/tde-08102012-151355/.

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A peritonite neutrofílica induzida por glicogênio acarreta antinocicepção em camundongos submetidos ao teste de contorção abdominal, a qual é mediada por uma proteína ligante de cálcio, com peso molecular de 14 kDa, denominada S100A9. O objetivo do presente trabalho foi aprofundar o estudo sobre o envolvimento dos neutrófilos na antinocicepção induzida pelo glicogênio em ratos submetidos ao teste de pressão de pata e avaliar a expressão da proteína S100A9 nos tempos onde foi detectado esse efeito. O glicogênio induz antinocicepção em ratos entre 2 e 12 horas após sua injeção intraplantar. O pré-tratamento dos animais com fucoidina, um inibidor de selectinas, não só reverte o efeito antinociceptivo observado como também induz hiperalgesia entre 2 e 6 horas após a injeção do glicogênio. Após 8 horas do tratamento com glicogênio, a fucoidina apenas inibiu a antinocicepção induzida pelo agente inflamatório. A análise histológica demonstrou um aumento na migração de células polimorfonucleares entre 2 e 8 horas após a administração de glicogênio, a qual foi inibida pelo pré-tratamento com fucoidina. Tanto a injeção subcutânea como intraplantar de naloxona, um inibidor inespecífico de receptores opioides, não interferiram no efeito antinociceptivo induzido pelo glicogênio, em nenhum dos tempos avaliados. Quanto à expressão da S100A9, analisada por "Western Blotting", foi observado que as amostras obtidas do coxim plantar dos animais injetados com o glicogênio, entre 2 e 12 horas, apresentaram uma banda com peso molecular aproximado de 14 kDa, o qual equivale ao peso da proteína S100A9. A quantificação das bandas marcadas com o anticorpo anti-S100A9, nos tempos entre 2 e 12 horas, demonstrou um aumento significativo da expressão dessa proteína nas amostras obtidas dos animais tratados com glicogênio, em comparação com os tratados com salina. A injeção intraperitoneal de glicogênio induziu um aumento significativo no número total de células presentes na cavidade abdominal dos animais entre a 2º e a 12º hora após o tratamento, representado pelo aumento do número de células polimorfonucleares migradas. Os sobrenadantes obtidos do exsudato peritoneal entre 2 e 12 horas após a injeção de glicogênio, administrados via intraplantar, não só reverteram a hiperalgesia induzida pela carragenina (Cg) como induziram efeito antinociceptivo. Já, o sobrenadante obtido após 24 horas da injeção de glicogênio reverteu apenas parcialmente o efeito hiperalgésico induzido pela Cg. O tratamento do sobrenadante obtido 4 horas após a injeção do glicogênio com o anticorpo anti-S100A9 aboliu totalmente o efeito antinociceptivo observado com esse sobrenadante sobre a hiperalgesia induzida pela Cg. Esses dados sugerem que a antinocicepção acarretada pelo glicogênio em ratos submetidos ao modelo de pressão de pata é dependente da migração neutrofílica, não está relacionado à liberação de peptídeos opioides, mas possivelmente à secreção da proteína S100A9 por essas células. Ainda, os resultados obtidos com os sobrenadantes do exsudato peritoneal após a injeção do glicogênio, demonstram que durante a peritonite neutrofílica é secretada uma molécula capaz tanto de inibir a hiperalgesia acarretada pela carragenina quanto induzir antinocicepção, a qual possivelmente é a proteína S100A9.
Neutrophilic peritonitis induced by glycogen causes antinociception in mice subjected to the writhing test, which is médiated by a calcium-binding protein with a molecular mass of 14 kDa, named S100A9. The purpose of this study was to deepen the study on the involvement of neutrophils in glycogen-induced antinociception in rats subjected to the paw pressure test and evaluate the expression of S100A9 protein in time periods when this effect was detected. Glycogen induces antinociception in rats between 2 and 12 hours after intraplantar injection. Pretreatment of animals with fucoidan, a selectin inhibitor, not only reversed the antinociceptive effect, but also induces hyperalgesia between 2 and 6 hours after glycogen injection. Eight hours after treatment with glycogen, fucoidan only inhibited the antinociception induced by the inflammatory agent. Histological analysis showed an increased migration of polymorphonuclear cells between 2 and 8 hours after glycogen administration, which was inhibited by pretreatment with fucoidan. Both intraplantar and subcutaneous injection of naloxone, a nonspecific inhibitor of opioid receptors, did not affect the antinociceptive effect induced by glycogen at all evaluated times. In relation to the expression of S100A9 analyzed by Western blotting, it was observed that the samples obtained from the footpad injected with glycogen, between 2 and 12 hours, had a band with a molecular weight of 14 kDa, which is similar to molecular weight of S100A9. Relative quantification of the bands marked with anti-S100A9 in the time periods between 2 and 12 hours showed a significant increase in protein expression in samples obtained from animals treated with glycogen, compared with those treated with saline. Intraperitoneal injection of glycogen induced a significant increase in the total number of cells in the abdominal cavity of animals between 2 and 12 hours after treatment, represented by increased numbers of migrated polymorphonuclear cells. The supernatants obtained from peritoneal exudate between 2 and 12 hours after injection of glycogen, administered intraplantarly, not only reversed the hyperalgesia induced by carrageenan (Cg) but also induced antinociceptive effect. Already, the supernatant obtained 24 hours after injection of glycogen only partially reversed the hyperalgesic effect induced by Cg. The treatment of the supernatant obtained 4 hours after injection of glycogen with anti-S100A9 abolished the antinociceptive effect observed with the supernatant on hyperalgesia induced by Cg. These data suggest that antinociception entailed by glycogen in rats submitted to the paw pressure is dependent on neutrophil migration. Moreover, this effect is not related to the release of opioid peptides but possibly to the S100A9 protein secretion by these cells. In addition, the results obtained with the supernatants of peritoneal exudate after glycogen injection show that during neutrophilic peritonitis a molecule able to inhibit carrageenan-induced hyperalgesia is secreted and induce antinociception entailed by glycogen, which is possibly the S100A9 protein.
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41

Liu, Yidong. "Design, synthesis and evaluation of S100A4 protein inhibitors." Thesis, University of Nottingham, 2015. https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.738338.

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S100A4 is a 101-amino acid protein belong to a largest sub group of EF-hand calcium binding proteins, and has been described as having both intracellular and extracellular functions. Human S100A4 is the best characterized member of the S100 protein family in terms of its role in cancer and metastasis formation. Overexpression of S100A4 has been observed in several metastatic cancers. It is recognized that an increased level of S100A4 expression correlates with a high incidence of metastasis and poor prognosis for cancer patients. Therefore S100A4 is regarded as a practical target for cancer treatment. The work of investigating S100A4 inhibitors is presented in this thesis. Using the fluorescence resonance energy transfer (FRET) method, a biochemistry assay for monitoring the binding between S100A4 and two of its targets, annexin A2 and myosin IIA, was successfully established. By using this FRET assay, 89 3-hydroxy-1H-pyrrol-2(51-1)-one compounds were screened against the binding of S 100A4 to an annexin A2 (1-14) peptide. 68 compounds were found to be active to inhibit the interaction, exhibiting a different degree of potency. A structure activity relationship (SAR) of all active compounds was established, supported by the predicted binding poses from docking studies. Guided by these SAR conclusions, 13 novel compounds were designed and synthesized based on the 3-hydroxy-1H-pyrrol-2(5H)-one scaffold in order to find better S100A4 inhibitors as well as to further confirm the SAR study. Activities of these new chemicals against both S100A4-annexin A2 complex and S100A10-annexin A2 complex were examined showing very interesting results of different potencies against the two different targets. Docking studies revealed an alternative binding pose, which could be used to explain the potencies and selectivity of novel 3-hydroxy-1H-pyrrol-2(51)-one inhibitors. Two compounds with high S100A4 selectivity were capable of inhibiting the interaction of S100A4 with surface annexin A2 of MDA-231 breast cancer cells In conclusion, this work for the first time identified a series of 3- hydroxy-1H-pyrrol-2(5H)-one compounds as S100A4-annexin A2 inhibitors. The effectiveness of inhibiting S100A4-annexin A2 interaction on cell surface has been proved by selected compounds. As S100A4 plays an important role in cancer metastasis, the results described in this thesis, including the screening method, compounds synthesizing and docking studies, are very meaningful and important to fully understand the specific role of S100A4 in cancer progression in future. This could be a promising start for the development of new cancer treatments.
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42

Sack, Ulrike. "New insights into S100A4-induced colon cancer metastasis." Doctoral thesis, Humboldt-Universität zu Berlin, Mathematisch-Naturwissenschaftliche Fakultät I, 2011. http://dx.doi.org/10.18452/16313.

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S100A4 spielt eine zentrale Rolle für die Metastasierung des Dickdarmkrebses. Die Hemmung der S100A4 Expression stellt damit einen vielversprechenden therapeutischen Ansatz dar. Die vorliegende Arbeit präsentiert Niklosamid und Calcimycin als neue Inhibitoren der S100A4 Transkription. In Kolonkarzinomzellen, die mit einem der beiden Inhibitoren behandelt wurden, wurde die S100A4 Expression konzentrations- und zeitabhängig unterdrückt. Des Weiteren war die Zellmigration und -invasion in Abhängigkeit von S100A4 in behandelten Zellen vermindert. Niklosamid und Calcimycin Behandlung verhinderten die Zellproliferation und die Koloniebildung von Kolonkarzinomzellen. Beide Inhibitoren hemmten den konstitutiv aktiven Wnt Pathway von Kolonkarzinomzellen. Calcimycin Behandlung verminderte die Expression von beta-catenin. Niklosamid hemmte die Bildung des beta-catenin/TCF Komplexes und unterband damit die Expression von Wnt Pathway Genen, wie z.B. S100A4. Im Rahmen dieser Arbeit wurde ein in vivo Tiermodell entwickelt, mit dem die S100A4-induzierte Metastasierung mit Hilfe von nicht-invasivem Biolumineszenz Imaging visualisiert werden konnte. In diesem Model konnte gezeigt werden, dass Niklosamid signifikant die S100A4 Expression im Tumor vermindert und damit die Metastasierung hemmt. Des Weiteren zeigt diese Arbeit, dass S100A4 die Expression des Wnt Pathway Antagonisten DKK-1 in Kolonkarzinomzellen hemmt. DKK-1 selbst konnte als endogener Inhibitor der S100A4 Expression identifiziert werden. Zusammenfassend beschreibt die vorliegende Arbeit einen neuen regulativen Mechanismus im Wnt Pathway, der die S100A4 Expression im Kolonkarzinom fördert. Diese Beobachtung verdeutlicht die Notwendigkeit für wirksame S100A4 Inhibitoren, wie Niklosamid und Calcimycin, die das Potenzial haben, in einer klinischen Anwendung die Metastasierung von Kolonkarzinompatienten mit erhöhter S100A4 Expression zu hemmen und damit deren Überlebenschance wesentlich zu verbessern.
S100A4 promotes metastasis in colon cancer patients thereby reducing their five-year survival chances to less than 10%. Consequently, inhibition of S100A4 expression is a promising strategy for anti-metastatic treatment of colon cancer patients. The present study characterizes the small molecules niclosamide and calcimycin as transcriptional inhibitors of S100A4 which reduced S100A4 expression concentration- and time-dependently. Niclosamide and calcimycin treatment restricted cell migration, invasion and wound healing capabilities in a S100A4-specific manner, and inhibited cell proliferation and colony formation of colon cancer cells. Both small molecule inhibitors interfere with the constitutively active Wnt pathway. Targeting β-catenin expression by calcimycin or interfering with the β-catenin/TCF transcription activating complex by niclosamide resulted in reduced Wnt target gene transcription, among them S100A4. The study further presents a human colon cancer xenograft mouse model for monitoring S100A4-induced metastasis formation via non-invasive bioluminescence imaging. Treatment of xenograft mice with niclosamide resulted in a significant reduction of the S100A4 mRNA level in the tumor accompanied by inhibition of metastasis formation. Moreover, this study presents evidence that S100A4 is an inhibitor of DKK-1 expression. In colon cancer cells DKK-1 and S100A4 expression was negatively correlated. Ectopic S100A4 overexpression inhibited DKK-1 expression. Targeting S100A4 via shRNA recovered the repressed DKK-1 expression and vice versa. In summary, the study describes a novel positive feedback loop in the Wnt pathway regulation formed by S100A4 repressing its antagonist DKK-1. This novel mechanism further strengthens the need for S100A4 inhibitors such as niclosamide or calcimycin. Consequently, such small molecules provide immense potential for the treatment of colon cancer patients who are at high risk for S100A4-induced colon cancer metastasis.
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43

Jervis, T. J. "Crystallisation and structural studies of bifunctional enzyme and S100A4." Thesis, Keele University, 1998. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.267460.

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44

Melo, Bruno Marcel Silva de. "Alarmina S100A9: um mediador crítico no desenvolvimento da psoríase." Universidade de São Paulo, 2017. http://www.teses.usp.br/teses/disponiveis/17/17147/tde-06042018-094810/.

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A psoríase (Ps) é uma doença inflamatória crônica-imunomediada da pele, caracterizada por proliferação acentuada e diferenciação anormal de queratinócitos e aumento do infiltrado de células inflamatórias na derme. S100A9 é um alarmina que é produzida por queratinócitos e células mielóides em condições inflamatórias. No entanto, o papel desta molécula no desenvolvimento e manutenção da resposta inflamatória da Ps permanece desconhecida. Nesso objeitvo foi investigar o papel de S100A9 no desenvolvimento da psoríase. Análises de bioinformática de um banco de dados disponível on-line contendo valores de expressão de gênica de humanos mostrou que a expressão de S100A9 está aumentada pele lesionada de pacientes com Ps. Esses dados foram confirmados por imunofluorescência e Western blot onde foi observado um aumento na expressão de S100A9 na pele lesionada de pacientes com Ps, em comparação com amostras de pele não lesionada desses mesmo pacientes. Estes níveis de S100A9 foram positivamente correlacionados com a expressão de queratina-17, um marcador de ativação de queratinócitos. Para investigar o papel do S100A9 no desenvolvimento de Ps, autilizamos o modelo de Ps induzido por aplicação tópica de imiquimode (IMQ) nas costas de de camundongos WT, S100A9 - / - ou camundonos previamente tratados com paquinimod (10mg / kg, vo ), um quelante de S100A9. A exposição ao IMQ induziu o aumento da expresão gênica de S100a9 e proteica de forma rápida e dependente do tempo na pele e nos linfonodos drenantes da pele, e esse aumento permaneceu elevado até o final do experimento (6º dia). Notavelmente, a inflamação, e espessura da pele foram significativamente reduzidas em camundongos tratados com PAQ ou camundongos S100A9 -/- em comparação com camundongos WT. Os parâmetros histológicos confirmam a redução da espessura da epiderme, mostrada por seções histológicas coradas com HE. Para determinar quais células produtoras de S100A9 contribuem para o desenvolvimento de Ps, realizamos uma quimera e mostramos que ambos os queratinócitos e células mieloides são importantes para a produção de s100a9 e contribuem para o desenvolvimento da psoríase. No entanto os queratinócitos parecem ser mais importantes no aumento da espessua e na lesão da pele. Além disso, a expressão de Il23, na pele de animais S100A9 -/- ou tratados com PAQ foi reduzida, o que poderia explicar a redução das linfócitos T gamma-delta IL-17 nos linfonodos desses mesmos camundongos. Nosso trabalho mostrou que o alarmina S100A9 desempenha um papel importante no desenvolvimento da psoríase. Assim, S100A9 poderia ser uma estratégia futura para o tratamento farmacológico da psoríase. Além disso essa proteína poderia ser usada como marcador da atividade da doença
Psoriasis (Ps) is an immune-mediated chronic inflammatory skin disease, characterized by accentuated proliferation and abnormal differentiation of keratinocytes and infiltration of inflammatory cells in the dermis. S100A9 is an alarmin that is produced by keratinocytes and myeloid cells in inflammatory conditions. However, the role of this molecule in the development and maintenance of the inflammatory response in Ps remains not well understood. Herein, we investigated the role of S100A9 in the development of psoriasis. Bioinformatical analysis of an online database containing human gene expression information showed that the s100a9 is overexpressed in lesional skin from Ps patients. These data were confirmed by immunofluorescence and western blot that showed an overexpression of s100a9 in the lesional skin from Ps patients compared with paired samples of nonlesional psoriatic skin. These levels of s100a9 were positively correlated with the expression of keratin-17, a keratinocyte activation marker. To investigate the role of S100A9 in the development of Ps, psoriasis-like skin inflammation was induced by topical application of imiquimod (IMQ) on the back skin of S100A9-deficient mice (S100A9-/-) or paquinimod (10mg/kg, v.o) pretreated mice. IMQ exposure induced s100a9 mRNA and S100A9 protein expression in a rapid and time-dependent manner in the skin and lymph node of mice and remained elevated until the end of the experiment (6th day). Notably, inflammation, assessed by epidermal thickness measurement and H&E-stained histological sections, was significantly reduced in S100A9-/- or paquinimod treated-mice compared with wild-type (WT) control mice. To determine which S100A9- producing cell contributes to the Ps development we performed a chimera and showed that both keratinocytes and myeloid cells are important for the production of s100a9 and contribute to the development of psoriasis. However keratinocytes seems to be most important to development of lesion skin. Moreover, the expression of IL-23, in the skin, was reduced, which might explain the reduction of IL-17-producing gamma-delta T cells in the lymph nodes of S100A9-/- or paquinimod-treated mice. We showed that the alarmin S100a9 plays an important role in the development of psoriasis. Thus, targeting S100A9 could be a future strategy for pharmacological treatment of psoriasis and this protein can be used as a marker of disease activity.
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45

Otterbein, Ludovic R. "Etudes cristallographiques de l'actine et de la S100A6 humaine." Aix-Marseille 1, 2002. http://www.theses.fr/2002AIX11018.

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Dans la cellule eucaryote, l'actine est une protéine impliquée dans de nombreuses fonctions biologiques où elle joue un rôle dans la mobilité, la modification de l'aspect des cellules et dans la contraction musculaire. Nous avons déterminé la structure cristallographique de l'actine monomérique sous forme ADP à la résolution de 1,54 Å. Cette structure montre des changements conformationnels de la protéine lors de la libération du Pi du site catalytique. De plus, l'utilisation de la tétraméthylrhodamine-5-maléimide pour bloquer la polymérisation de l'actine permet dorénavant d'envisager la co-cristallisation de complexes de l'actine avec de nombreuses protéines qui interagissent avec celle-ci, mais qui contrairement à toutes celles étudiées jusqu'à présent ne permettent pas de prévenir sa polymérisation. Dans le muscle lisse, caldesmon, une protéine liant l'actine, joue un rôle important dans la régulation de la contraction musculaire. Cette protéine est régulée par des protéines liant le calcium, telles que la calmoduline et la S100A6. Nous avons déterminé les structures de la S100A6 avec et sans calcium. La liaison du calcium induit un large changement conformationnel ainsi qu'une modification des charges du dimère de S100A6 aboutissant à l'exposition de deux sites de liaison de cibles naturelles diamétralement opposés. Ces résultats permettent de classer la S100A6 et de manière plus globale les protéines S100 dans la famille des protéines "sensor" du calcium. La libération d'actine dans le flux sanguin peut être létal. Les structures de la "Vitamin D-binding protein" et de son complexe avec l'actine déterminées ici, apportent des informations importantes sur le rôle de l'actine dans le système de protection appelé "Actin-Scavenger System".
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46

Moraes, Natassja Foizer. "O C-terminal da proteína S100A9 murina modula os eventos envolvidos na angiogênese e na progressão tumoral em modelos in vitro." Universidade de São Paulo, 2015. http://www.teses.usp.br/teses/disponiveis/10/10133/tde-09122015-114330/.

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As proteínas S100A8/A9 são expressas em diferentes tipos celulares e quando sozinhas ou complexadas e em baixas concentrações, promoveram proliferação, migração celular e formação de estruturas capilares. Por outro lado, quando em altas concentrações, esse complexo inibe o crescimento de diversos tipos de células tumorais murinas e humanas. Ainda, tanto a proteína S100A9 humana, quanto um peptídeo sintético idêntico a porção C-terminal da proteína S100A9 murina (pS100A9m) possuem efeitos antinociceptivo e imunorregulatório. Apesar dessas evidencias, até o momento não foi investigado o efeito do pS100A9m sobre a angiogênese e a tumorigênese. Portanto, o objetivo do presente estudo foi investigar, in vitro, o efeito do pS100A9m sobre os eventos fundamentais envolvidos com a angiogênese e o desenvolvimento tumoral. Para tanto, a fim de avaliar o efeito do pS100A9m sobre a angiogênese foi utilizada a linhagem de células endoteliais tímicas murinas (tEnd.1) nos ensaios de proliferação, migração da célula endotelial em meio de cultura, avaliada nos modelos de wound healing e transwell ou migração em meio condicionado, obtido de células tumorais LLC WRC256, avaliada no modelo de transwell, ensaio de adesão (aos componentes de matriz, tais como o colágeno tipo I, fibronectina e laminina) e formação de tubos em matrigel tridimensional (3D). Para os estudos sobre o efeito do pS100A9m sobre as células tumorais, foi utilizada a linhagem de células LLC WRC256 para realização dos ensaios funcionais de proliferação, migração (wound healing) e adesão (sobre os componentes da matriz extracelular). Os resultados obtidos demonstraram que o pS100A9m inibe a proliferação, migração, adesão sobre os componentes de matriz e, consequentemente, a formação de estruturas capilares em matriz 3D. Em relação às células tumorais LLC WRC256, foi observada, novamente, a ação inibitória do pS100A9m sobre os eventos de proliferação e migração. Em relação à adesão, o peptídeo aumentou a capacidade de adesão das células tumorais sobre o colágeno tipo I e fibronectina, porém inibiu a adesão dessas células sobre laminina. Em conclusão, os dados aqui obtidos demonstram que o pS100A9m inibe in vitro os eventos fundamentais envolvidos com a angiogênese e com a progressão tumoral. Desta forma, o peptídeo da porção C-terminal da proteína S100A9 pode ser considerado uma nova ferramenta para o estudo da angiogênese e tumorigênese, além apresentar potencial para uma possível aplicação terapêutica nesses processos
The S100A8/A9 proteins are expressed in different cell types and alone or when complexed, and at low concentrations promoted proliferation, cell migration and formation of capillary structures. On the other hand, at higher concentrations, this compound inhibits the growth of many types of murine and human tumor cells. Moreover, both human S100A9 protein and a synthetic peptide identical to the C-terminal portion of murine S100A9 (mS100A9p) present antinociceptive and immunomodulatory effects. Despite these evidences, the effect of mS100A9p on angiogenesis and tumorigenesis has not been investigated. Therefore, the aim of this study was to investigate the in vitro effect of mS100A9p on crucial events involved in angiogenesis and tumor development. For this, in order to evaluate the effect of mS100A9p on angiogenesis was used the murine endothelial cell line derived from thymus hemangioma (tEnd.1) for proliferation assays, endothelial cell migration in the presence of culture medium (scratch wound healing and chemotaxis assays) or in conditioned medium prevenient from LLC WRC256 tumor cells (chemotaxis assays), adhesion assay (on extracellular matrix components, such as type I collagen, fibronectin and laminin) and tube like-structure formation in 3D matrix. For the analyzes of the effect of mS100A9p on tumor cells, the cell line LLC WRC256 was used to perform functional assays such as proliferation, migration (scratch wound healing model) and adhesion (on components of the extracellular matrix). The results showed that the mS100A9p inhibits the proliferation, migration and adhesion of endothelial cells to the matrix components and consequently the formation of capillary structures in 3D matrix. Regarding LLC WRC256 tumor cells, it was observed again the inhibitory action of the mS100A9p on proliferation and migration events. In relation to cellular adhesion, this peptide increased this parameter of tumor cells on type I collagen and fibronectin. However mS100A9p inhibited the adhesion of these cells on laminin. In conclusion, the data obtained show that the mS100A9p inhibits in vitro crucial events involved in angiogenesis and tumor progression. Thus, the C-terminal portion of murine S100A9 protein may be considered as a new tool for the study of tumorigenesis and angiogenesis besides presenting potential to a possible therapeutic application in these processes
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47

Deol, Yadwinder S. "ROLE OF PSORIASIN (S100A7) IN ESTROGEN RECEPTOR POSITIVE BREAST CANCERS." The Ohio State University, 2012. http://rave.ohiolink.edu/etdc/view?acc_num=osu1338359283.

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48

Pietas, Agnieszka. "Identification of the tumour-associated gene S100A14 and analysis of its regulation." Doctoral thesis, Humboldt-Universität zu Berlin, Mathematisch-Naturwissenschaftliche Fakultät I, 2005. http://dx.doi.org/10.18452/15196.

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Durch Analyse der Subtraktion-cDNA Bibliothek einer humanen Lungentumor Zelllinie haben wir ein neues Mitglied der S100 Genfamilie identifiziert und charakterisiert, welches S100A14 benannt wurde. Die vollständige cDNA hat eine Länge von 1067 bp und kodiert für ein Protein von 104 Aminosäuren, welches die S100-spezifische Kalzium-bindende Domäne enthält. Das Gen wird in normalen humanen Epithelien ubiquitär exprimiert, zeigt jedoch Expressionsverluste in vielen Tumorzelllinien. Im Gegensatz zu Tumorzelllinien ist S100A14 auf mRNA- und Proteinebene in vielen humanen Primärtumoren stärker exprimiert, unter anderem in Lungen- und Brustkarzinomen. Um den Mechanismus der erhöhten S100A14 Expression in Lungen- und Brustkarzinomen zu verstehen, haben wir die Effekte des EGF (epidermal growth factor) und des TGF-alpha (transforming growth factor-alpha) untersucht. Beide Faktoren sind Liganden des ERBB Rezeptors und induzieren in der immortalisierten bronchialen Epithelzelllinie S100A14 Expression. Unter Verwendung spezifischer Inhibitoren konnte gezeigt werden, dass für die EGF-vermittelte transkriptionelle Induktion der ERK1/2 Signalweg (extracellular signal-regulated kinase) verantwortlich ist und eine de novo Proteinsynthese erfordert. Diese Ergebnisse unterstützend konnte immunhistologisch eine signifikante Korrelation zwischen der Überexpression von ERBB2 und S100A14 in primären Brustkarzinomen nachgewiesen werden. Phorbolester-12-Myristat-13-Acetat (PMA) verstärkte gleichfalls die S100A14 mRNA Expression in 9442 Zellen, was eine Regulation durch die Protein Kinase C (PKC) vermuten lässt. Die PMA-induzierte Expression von S100A14 wird ebenso wie die TGF-alpha/EGF-Induktion durch die Aktivierung des ERK1/2 Signalweges vermittelt. In Anbetracht der großen Bedeutung der ERK1/2 und PKC Signalwege in der Tumorentstehung und Tumorprogression ist zu vermuten, dass S100A14 über die aberrante Regulation dieser Signalwege an die maligne Transformation gekoppelt ist.
By analysing a human lung tumour cell line subtraction cDNA library, we have identified and characterized a novel member of the human S100 gene family that we designated S100A14. The full-length cDNA is 1067 bp and encodes a putative protein of 104 amino acids. The predicted protein contains the S100-specific EF-hand calcium-binding domain. The gene is ubiquitously expressed in normal human tissues of epithelial origin. S100A14 transcript was found to be down-regulated in many immortalized and tumour cell lines from diverse tissues. In contrast to the tumour cell lines, S100A14 shows up-regulation at the mRNA and protein level in many human primary tumours, including lung and breast carcinomas. To elucidate mechanisms whereby S100A14 expression is enhanced in lung and breast tumours, we studied the effects of epidermal growth factor (EGF) and transforming growth factor-alpha (TGF-alpha) on its expression. Both are ligands of ERBB receptor and induced S100A14 expression in the immortalized bronchial epithelial cells. By use of specific inhibitors, we found that EGF-mediated transcriptional induction of S100A14 involves extracellular signal-regulated kinase (ERK1/2) signalling and requires de novo protein synthesis. In support of these findings, we demonstrated by immunohistochemistry a significant correlation between ERBB2 and S100A14 protein overexpression in primary breast carcinomas. Our studies showed that the phorbol ester 12-myristate 13-acetate (PMA) increases S100A14 mRNA expression in immortalized bronchial epithelial cells suggesting regulation by protein kinase C (PKC). Similar to TGF-alpha/EGF induction, the PMA-induced S100A14 expression was also mediated by activation of the ERK1/2 signalling cascade. Considering the importance of the ERK1/2 and PKC signalling pathways in tumour development and progression we suggest that it is the aberrant regulation of these signalling cascades that couples S100A14 to malignant transformation.
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49

Moroz, Olga. "Structural studies on human S100A12." Thesis, University of York, 2003. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.403963.

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50

Hoffmann, Roman, and Sebastian Uljas Lutz. "The health knowledge mechanism: evidence on the link between education and health lifestyle in the Philippines." Springer, 2018. http://dx.doi.org/10.1007/s10198-017-0950-2.

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Studies have found substantial differences in health-related behavior and health care usage between educational groups, which may explain part of the well-documented educational gradient in health. The allocative efficiency hypothesis offers a behavioral explanation for these reported differences. According to this theory, the educated possess more health knowledge and information, allowing them to make better health choices. We perform a mediation analysis to study this mechanism using original survey data from the Philippines, a lower-middle-income country. As an extension of previous empirical research, we construct a comprehensive index that captures different dimensions of health knowledge. Using generalized propensity scores, we find strong support for the allocative efficiency argument. Schooling is significantly associated with health knowledge levels, which explain up to 69% of the education effect on health lifestyle. This corresponds to twice the mediation strength of economic resources, suggesting an important role of this factor in explaining education effects on health decisions.
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