Dissertations / Theses on the topic 'Coculture'
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Jing, Duohui. "Mobilisation, Isolation and Coculture of Haematopoietic Stem Cells." Doctoral thesis, Saechsische Landesbibliothek- Staats- und Universitaetsbibliothek Dresden, 2011. http://nbn-resolving.de/urn:nbn:de:bsz:14-qucosa-39915.
Full textApple, Allon Aliza. "Bilaminar coculture of stem cells and instructive cells for tissue regeneration." Diss., Search in ProQuest Dissertations & Theses. UC Only, 2009. http://gateway.proquest.com/openurl?url_ver=Z39.88-2004&rft_val_fmt=info:ofi/fmt:kev:mtx:dissertation&res_dat=xri:pqdiss&rft_dat=xri:pqdiss:3390115.
Full textSource: Dissertation Abstracts International, Volume: 71-02, Section: B, page: . Adviser: Jeffrey C. Lotz.
Hinkerohe, Daniel. "Effects of cytokines on microglial phenotypes and astroglial coupling in an inflammatory coculture model /." Bochum, 2006. http://opac.nebis.ch/cgi-bin/showAbstract.pl?sys=000253108.
Full textBernard, Yohann. "Stress oxydatif, inflammation vasculaire et métalloprotéinases : étude in vitro sur un modèle de coculture." Thesis, Nancy 1, 2008. http://www.theses.fr/2008NAN10067/document.
Full textDuring atherosclerosis leucocytes invade the vascular wall, inducing inflammation and production of oxidative stress by reactive oxygen species (ROS). We tested the effects of an oxidative stress and/or potential interactions between a neutrophil model (?HL60) and human coronary endothelial (HCAEC) or smooth muscle (HCSMC) cells, on ?HL60 mobility and production and activity of cellular metalloproteinases. Cell passaging of the promyelocytic HL60 cell line, differentiated by DMSO in a neutrophil model (?HL60), induces variations in cell mobility and production of MMP9. ROS from biochemical or cellular sources did not modify MMP2 or MMP9 activity in HCAEC or HCSMC. There is no modification of MMPs activities in ?HL60/HCAEC cocultures, but stimulation of ?HL60 MMP9 activity in ?HL60/HCSMC cocultures. Basal migration capacities and N-formyl-L-Methionyl-L-Leucyl-L-Phenylalanine -stimulated invasion abilities of ?HL60 increase in presence of HCSMC. Antioxidant enzymes barely change ?HL60 mobility, increase expression and production of ?HL60 MMP9 and seem to reduce the stimulating effect of HCSMC on ?HL60 MMP9 production. HCSMC also express and/or secrete some cytokines (IL8, IL6, IL1?, CCL2, CXCL12) implicated in atherosclerosis. In conclusion, interactions between ?HL60 and HCSMC induce an increase in MMP9 secretion, which is modulated by ROS, and a stimulation of ?HL60 mobility. Expression by HCSMC of inflammatory cytokines implicated in atherosclerosis allows to identify potential candidates responsible for the secretory and/or migratory response of ?HL60
L'Herondelle, Killian. "Etude sur neurones sensoriels et kératinocytes des mécanismes cellulaires et moléculaires impliqués dans le prurit de la ciguatéra." Thesis, Brest, 2016. http://www.theses.fr/2016BRES0115.
Full textCiguatera fish poisoning (CFP) is a seafood poisoning occurring after contaminated fish fleshes ingestion containing toxins called « ciguatoxines » (CTXs). This illness, originating from tropical and subtropical areas, is an economic and health problems which becomes substantial in relation to international tropical fishes export and tourism development, as well as global warming rise. Those factors contribute to CFP sprouting in non-endemic temperate climate regions which were not until then concerned by CFP. Economic and health stakes of CFP are important since no reliable and ready-to-use detection system for CTXs in fishes have been developed, along with no relevant cure has been established to treat CFP.Pruritus, medical term refer to itch, is a clinical sign usually associated to skin diseases which strongly alter patients’ quality of life. Last decades, several studies allowed to better understand pruritus pathophysiology. Interestingly, people suffering from CFP frequently present pruritus, hence designation “La Gratte” or “La Gratel (le)” employed in endemic areas.The aim of these works was to study cellular and molecular mechanisms of CTXs at the root of neurological cutaneous troubles occurring in CFP. Here, we evaluated CTXs effects on in vitro model composed of sensory neurons cocultived with primary keratinocytes, quantifying neuropeptides known to be involved in pruritus. Compiling knowledges about CFP and pruritus pathophysiology, some antagonists were tested to neutralize CTXs-mediated neuropeptide release. To deal with signaling pathways in depth of neuropeptide exocytosis induced by CTXs, mechanism known to be accurately regulated by calcium homeostasis, calcium imaging experiments were performed.Results obtained in this project confirm the use of such a model to elucidate cellular mechanism of CFP pruritus, but also constitute an alternative in vitro tool to study chemicals inducing abnormal cutaneous senses. Among antagonists tested, one stands out from the crowd and was proved to be effective to inhibit CTXs-evoked effects studied. Those originals results, collected with antagonist of pruritus mediator, show new and promiscuous therapeutic prospects for future health concern
Janny, Laurent. "Coculture embryonnaire en fecondation in vitro humaine : etude d'une serie prospective randomisee de 606 ponctions." Clermont-Ferrand 1, 1994. http://www.theses.fr/1994CLF1BOO1.
Full textLease, Christopher William Minto, and Lease Chris@saugov sa gov au. "Biodegradation of High Molecular Weight Polycyclic Aromatic Hydrocarbons in Soils by Defined Bacterial and Fungal Cocultures." Flinders University. Biological Sciences, 2006. http://catalogue.flinders.edu.au./local/adt/public/adt-SFU20060803.114120.
Full textXu, Ruiling. "Investigating stroma-mediated resistance to gemcitabine, using a novel fluroescence-based coculture model of pancreatic cancer." Thesis, University of Cambridge, 2015. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.709342.
Full textHuppert, Cécile. "Développement d’un modèle de coculture cellules dendritiques lymphocytes T pour l’évaluation du danger des substances sensibilisantes." Thesis, Université de Lorraine, 2018. http://www.theses.fr/2018LORR0195/document.
Full textAllergies constitute an important issue in the field of occupational health and have a serious impact on the lives of workers. Occupational allergies are mainly contact and respiratory allergies and can be caused by low molecular weight chemicals. In the past, the tests that were used to identify the potential allergens were carried out on animals. However, European legislation has provided the impetus for reducing the use of animal testing to assess the sensitization potential of chemicals and promoted the development of alternative in vitro tests. In this context, we aimed to develop cell culture models to identify sensitizers. A first model using bone marrow derived dendritic cells (BMDC) from BALB/c mice was developed and showed promising results for identifying sensitizers and classify them according to their allergenic potency. Moreover, the Nrf2/Keap1 pathway seems to be involved in the response of this cell model to sensitizers. In order to supplement this model and to assess the functionality of BMDC, a BMDC-T cell (TC) coculture model was developed with a reference sensitizer before being tested on a range of reference sensitizers (cutaneous and respiratory sensitizers, irritants and non-sensitizers). The BMDC of our model, while exposed to sensitizers, were able to activate TC in coculture. Finally, preliminary tests using the cells of C57BL6/J mice in our coculture model showed that similar results to those obtained with cells from the BALB/c strain. The models of BMDC cultures and BMDC-TC coculture are promising for the development of alternative methods to animal experimentation assessing the sensitizing potential of chemicals
Madiedo-Podvršan, Sabrina. "Development of a lung-liver in vitro coculture model for the risk assessment of inhaled xenobiotics." Electronic Thesis or Diss., Compiègne, 2022. http://www.theses.fr/2022COMP2703.
Full textUrbanization and globalization are prevailing social phenomena that multiply and complexify the sources of modern pollution. Amongst others, air pollution has been recognized as an omnipresent life-threatening hazard, comprising a wide range of toxic airborne xenobiotics that expose man to acute and chronic threats. The defense mechanisms involved in hazardous exposure responses are complex and comprise local and systemic biological pathways. Due to this complexity, animal models are considered prime study models. However, in light of animal experimentation reduction (3Rs), we developed and investigated an alternative in vitro method to study systemic-like responses to inhalationlike exposures. In this context, a coculture platform was established to emulate interorgan crosstalks between the pulmonary barrier, which constitutes the route of entry of inhaled compounds, and the liver, which plays a major role in xenobiotic metabolism. Both compartments respectively comprised a Calu-3 insert and a HepG2/C3A biochip which were jointly cultured in a dynamically-stimulated environment for 72 hours. The present model was characterized using acetaminophen (APAP), a well-documented hepatotoxicant, to visibly assess the passage and circulation of a xenobiotic through the device. Two kinds of models were developed: (1) the developmental model allowed for the technical setup of the coculture, and (2) the physiological-like model better approximates a vivo environment. Based on viability, and functionality parameters the developmental model showed that the Calu-3 bronchial barrier and the HepG2/C3A biochip can successfully be maintained viable and function in a dynamic coculture setting for 3 days. In a stress-induced environment, present results reported that the coculture model emulated active and functional in vitro crosstalk that seemingly was responsive to high (1.5 and 3 mM) and low (12 and 24 μM) xenobiotic exposure doses. Lung/liver crosstalk induced modulation of stress response dynamics, delaying cytotoxicity, proving that APAP fate, biological behaviors and cellular stress responses were modulated in a broader systemic-like environment
MICHEL, MARTINE. "Interets et limites des cocultures cellulaires : a propos de deux exemples." Strasbourg 1, 1991. http://www.theses.fr/1991STR15078.
Full textKe, Xuedan. "Effet de l'homocystéine sur le phénotype des cellules musculaires lisses artérielles : effet direct ou dysfonction endothéliale ?" Thesis, Aix-Marseille 2, 2010. http://www.theses.fr/2010AIX22952/document.
Full textPhenotype switching of arterial smooth muscle cells (SMC) from a contractile phenotype through a synthetic phenotype in response to pathogenic stimuli is involved in the development of arteriosclerosis. It is well established that homocysteine (HCY) induces arteriosclerosis in elastic arteries. This pathologic arterial remodelling is characterized by the accumulation of SMC showing synthetic phenotype associated with an endothelial dysfunction. However, the effects of HCY on SMC phenotype are unclear. Since endothelial cells play a key role in the regulation of SMC phenotype, the goal of our study is to determine whether HCY modulates the SMC phenotype through a direct effect or through the induction of an endothelial dysfunction. We found that pathologic concentrations of HCY increase the proliferation of human arterial umbilical SMC in culture and increase their proteolytic potential through a reactive oxygen species dependant mechanism. We also found that HCY has not effect on the expression of type I and III collagen and fibronectin, as well as contractile proteins (SM a-actine, calponine hl, SMMHC et smootheline B). Using pre-conditionned or not pre-conditionned SMC by conditionned culture medium (MC) from human umbilical vein endothelial cells (HUVEC), we found that MC from HUVEC stimulated with 100µM of HCY prevent the inhibition of proliferation induced HUVEC and did not altered the expression of type I and III collagen and fibronectin, as well as contractile proteins. Our results suggest that HCY can directly modulate the SMC phenotype towards a synthetic phenotype. Although HCY as been previously shown to induce an endothelial dysfunction, this latter does not seem to be involve in the modulation of SMC phenotype associated with hyper homocysteinemia
Chamayou, Léo. "LiverPearls, une méthode de culture multicellulaire miniaturisée et à haut débit reproduisant l’environnement physiologique et la structure tridimensionnelle du foie humain." Thesis, Université Paris sciences et lettres, 2020. http://www.theses.fr/2020UPSLS005.
Full textInterest for new and more physiologically relevant liver models is high, particularly from pharmaceutical companies. Standard systems, like 2D culture, are indeed not enough predictive and better models are needed, either for drug candidates screening in ADME/Tox studies or for hepatic diseases modelling. To be closer to the human liver, a new model needs toreplicate liver structure and cellular composition better than the 2D. To this end, we used a micro-encapsulation technology, developed by the laboratory and based on the co-extrusion of a two-phases jet, composed of an alginate external phase and a cell-containing internal phase. This jet is then fragmented into micro-droplets and the alginate reticulated to form core-shell microcapsules. The porous alginate shell protects the cells from shear stress while letting oxygen and nutrients pass, and by preventing cell adhesion, enables the cells to self-assemble into hepatic spheroids which can bekept alive during one month, retain good functionality and can be used for high-throughput screening. This thesis focusedon using this technology to develop a next 3D liver model containing human primary hepatocytes, Kupffer cells and liver sinusoidal endothelial cells. Firstly, culture conditions for this model had to be optimized, particularly the ratio between these different cell types and the culture medium, which had to be suitable for these cell types. Then, once the culture conditions had been established, the model was characterized, structurally by immunofluorescence staining, and functionally by studying gene expression of important liver proteins, like cytochromes P450 or nuclear receptors. Enzymaticactivity, albumin and urea secretion were also studied. These capsules allow us to obtain a model able to replicate the complex interactions between these cell types and structurally closer to the human liver
Danoy, Mathieu. "Development of a physiologically-relevant in-vitro microfluidic model for monitoring of pancreatic cancer cells interactions with the liver." Thesis, Lille 1, 2017. http://www.theses.fr/2017LIL10093/document.
Full textThe cancer metastatic process and its understanding have been a major topic of interest for researchers in the past. Using in-vitro models in both standard culture conditions and in microfluidic devices, we investigated the feasibility of such models in the representation of the physiological in-vivo situation. We developed a hierarchical coculture model in PDMS plates, composed of hepatocytes, pericytes and endothelial cells. In different culture conditions, the influence of the different cells composing the model on the adhesion of cancer cells and promyeloblastic cells was investigated as well as the influence on the inflammatory state of the culture. To reproduce the in-vivo blood flow and shear stress to which the endothelial cells and the adhering cells are subjected, the model was then transferred into a microfluidic biochip. The device was composed of three channels, separated by micropillars and which could be filled independently one from another. Pericytes embedded in a hydrogel, hepatocytes, endothelial cells and finally pancreatic cancer cells could be inserted successively to reproduce the in-vivo hierarchical situation. Cells were found to viable after the culture and markers related to the liver and inflammation to be expressed. The influence of the presence of hepatocytes and pericytes was investigated by varying the culture conditions. It was found that pancreatic cancer cells were attracted by the cells in other channels in coculture. The established models lay the bases for more complex and relevant systems that could complement their in-vivo counterparts in the drug discovery process
Cruvellier, Nelly. "Etude et modélisation du compartiment nitrifacteur de la boucle MELiSSA : coculture sur ammonium et triculture sur urée." Thesis, Université Clermont Auvergne (2017-2020), 2017. http://www.theses.fr/2017CLFAC007/document.
Full textPhysico-chemical processes are used on the International Space Station for partial recycling of wastes in order to minimize the resupplies of oxygen and water. Further and longer explorations can only be possible if a life support system is applied to enhance autonomy to the station. MELiSSA is a biological life support system project aiming for waste recycling, water and air regeneration and production of simple food. The only way to assure these functions is the use of microorganisms which is requiring a high knowledge and a perfect control of processes implicated. The thesis objectives consist in developing a predictive model for the MELiSSA nitrifying compartment. First, a kinetic study of Nitrosomonas europaea ATCC® 19718 and Nitrobacter winogradskyi ATCC® 25391 in submerged bioreactors allowed defining a kinetic model of nitrification. Secondly, this model was combined to an N-tanks in series one to compose a nitrification model in fixed-bed biorectors : NitriSim. It was applied on a long-term experiment in a fixed-bed bioreactors where the bed was composed of Biostyr® beads. The last part of this work was about the use of a urea-degradating bacteria, Cupriavidus pinatubonensis, in the fixed-bed bioreactor. All of these results leaded to the development of a nitrification in fixed-bed reactors model and opened up interesting prospects for the urine degradation in the nitrifying compartment of MELiSSA
Frohwein, Thomas Armin [Verfasser]. "Untersuchung des Sensibilisierungspotenzials von ungesättigten Verbindungen im Loose-fit Coculture-based Sensitization Assay (LCSA) / Thomas A. Frohwein." Berlin : Medizinische Fakultät Charité - Universitätsmedizin Berlin, 2014. http://d-nb.info/1052221548/34.
Full textShim, Hojae. "BTEX degradation by a coculture of Pseudomonas putida and Pseudomonas fluorescens immobilized in a fibrous-bed bioreactor /." The Ohio State University, 1997. http://rave.ohiolink.edu/etdc/view?acc_num=osu1487945320759246.
Full textMesselmani, Taha. "Development and characterisation of a biomimetic liver on chip featuring 3D hepatic coculture with an endothelial barrier." Electronic Thesis or Diss., Compiègne, 2023. http://www.theses.fr/2023COMP2736.
Full textDuring drugs development programs, animal models are commonly used for the assessment of the metabolism and toxicity of drug candidates. Several legal frameworks are being settled to promote the replacement, the reduction, and the refinement of these experiments. The liver is a central organ involved in the detoxification of exogenous molecules. Accordingly, the development of models mimicking the functions of the liver remain a challenging objective. Conventionally, liver cells are cultured in vitro in 2D Petri dishes but this conformation leads to a rapid loss of their functions. In recent years, the association between tissue engineering and organ-on-chip technology led to the development of more accurate alternative models that mimic the liver functions. The aim of this thesis is to develop a biomimetic liver-on-chip platform by coupling a hepatocyte biochip and an endothelial-like barrier. The goal is to mimic the passage of molecules through the liver sinusoid endothelial barrier and then their metabolism with the hepatocytes. In the first part, we used organ-on-chip technology and ECM-based hydroscaffold to organise the cells in 3D structures. The potential of our model was compared with static Petri dishes and the spheroids formed were characterised structurally and functionally. In the second part, we characterized the formation of an endothelial barrier and identified specific markers indicating the conservation of the phenotype of endothelial cells. We established the coculture conditions and analysed the potential of coupling the endothelial barrier with the hepatocyte-on-chip to metabolize the APAP as a candidate molecule. Finally, we analysed the metabolomic signature of each condition, crosstalk between the cells, and identified the metabolic signature of APAP injury and described the reactions happening at metabolic level. In the last part, we proposed tracks of improvement by using primary hepatocytes or by integrating the endothelial barrier and the hepatocytes in the same bi-compartmentalized biochip
Gravel, Nicole. "Induction de la compétence au développement chez les ovules de porc par la coculture avec les cellules folliculaires." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1999. http://www.collectionscanada.ca/obj/s4/f2/dsk2/ftp01/MQ44711.pdf.
Full textDorchies, Olivier. "Systemes de coculture nerf-muscle permettant la differenciation musculaire tardive chez les mammiferes : etude morphologique, biochimique et fonctionnelle." Université Louis Pasteur (Strasbourg) (1971-2008), 2000. http://www.theses.fr/2000STR13202.
Full textKalman, Benoît. "Génération et optimisation de microtissus musculaires 3D in vitro." Thesis, Université Grenoble Alpes (ComUE), 2016. http://www.theses.fr/2016GREAI053.
Full textSkeletal muscle tissue engineering aims to build functional and physiological tissues in vitro in order to better understand myogenesis, to investigate the impact of genetic mutations and to screen potential therapies. Over the past few years, bi- and tridimensional models of muscle tissue have been developed, but most of these models are based on the use of murine cells and require large amounts of cells, thus limiting their relevance to study pathologies of human muscles and drug screening assays. Here we aimed at developing different models of human muscle microtissues to address these issues. By using microfabrication techniques, we first engineered a microgrooved platform we used to generate aligned multilayered skeletal muscle tissues from murine C2C12 myoblasts and human immortalized myoblasts. We showed the impact of topography and cell density on the maturation and myotube alignment. We then fabricated a microdevice, consisting of microwells containing two micropillars allowing an easy access to the contractility of muscle tissues. We engineered microtissues from C2C12 and C2C12 myoblasts electroporated with a mutated gene of desmin, and showed some limitation of this technique of transduction. Finally, we generated microtissues from human myoblasts. We investigated the role of the extracellular matrix in the tissue formation and evidenced the benefits of coculturing myoblasts and fibroblasts on the stability of muscle microtissues. Furthermore, we optimized the geometry of the micropillars to engineer and compare microtissues composed of human myoblasts isolated from healthy and diseased (Duchenne muscular dystrophy) patients. A proof of concept of the potential of this technology for screening chemical and gene therapies was established. We were indeed able to analyze in real time the effects of the Rho-associated kinase-inhibitor Y-27632 on the tissue contractility, as well as the transduction of a model fluorescent reporter gene. Altogether, the results of this work demonstrate the potential of this technology to study fundamental muscle biology, examine functional effects of patient-specific mutations or screen chemical and gene therapies
Hamidi, Jamal. "Etude des stades précoces de développement embryonnaire : coculture in vitro dans l'oviducte et sur mono couches de cellules épithéliales tubaires." Lyon, INSA, 1990. http://www.theses.fr/1990ISAL0022.
Full text[Embryos of many species of mammals do not lead to normal cleavage and development, with lost of viability, when they are manipulated in vitro out of their natural site. Two hypothesis are described in literature about the origin of this "Cell-block" : One is related to maternal cytoplasmic factors, the second one equally involves cytoplasm and nucleus. Our results, obtained with back-cross experiments, are in agreement with cytoplasmic hypothesis. In the study of oviduct-embryo relationships and of "embryo-trophic factors" implication, results are always contradictory, especially for hormone dependence (WHITTINGHAM, 1968 ; MINAMI et al. , 1988). Using the technique of coculture in prepubertal oviduct, without any serum addition or hormonal treatment, we can now assert the non hormone dependence of embryotrophic factors and the aptitude of prepubertal oviduct to sustain the early embryo development (HAMIDI et al. , 1988 ; MENEZO et al. , 1989). Moreover, we have demonstrated that the tubular secretions are not embryo dependent: embryo don't induce increased cAMP level nor amino acids influx in the oviduct. Furthermore, using a substitute of serum, Ultroser G, we obtained for the first time a confluent monolayers of epithelial cells derived from mouse oviduct. Embryo coculture on those monolayers allowed an important level of embryo development with maintenance of chronology, morphology and viability. This performance does not seem specie-specific nor strictly tissue-specific. About the metabolism of glucoside, the modification of culture medium by epithelial cells (monolayers), is in agreement with the observation of CHA TOT et al. (1989) ; however, this result is not confirmed by the use of other cell supports. ]
Behr, Steven [Verfasser], and Regine [Akademischer Betreuer] Willumeit-Römer. "Impact of magnesium based degradable alloys on a coculture model of osteoblast and osteoclast / Steven Behr ; Betreuer: Regine Willumeit-Römer." Hamburg : Staats- und Universitätsbibliothek Hamburg, 2020. http://d-nb.info/1211727270/34.
Full textFifani, Barbara. "Développement de stratégies de coculture favorisant l’amensalisme ou la coopération entre les agents de biocontrôle Bacillus velezensis et Trichoderma harzianum." Electronic Thesis or Diss., Université de Lille (2018-2021), 2021. http://www.theses.fr/2021LILUR054.
Full textUnderstanding the interaction between microorganisms is essential for the development of new biocontrol products. The fungus Trichoderma harzianum and the bacteria Bacillus velezensis are exploited for their antagonist activity against phytopathogens. Two coculture strategies of these two microorganisms were developed in order to determine the conditions leading to an interaction which increases the biocontrol activity of this couple, defined in terms of the production of lipopeptides by the bacteria. The culture medium essentially varies between these two strategies. The two media differ depending on the availability of nutrients for the microorganisms. In the medium where Bacillus and Trichoderma have all the necessary elements for their growth, the bacteria thrives at the expense of the fungus thanks to its faster growth rate and the production of antifungal lipopeptides. Sequential inoculation of Trichoderma followed by Bacillus solved these problems preventing the coexistence of the two microorganisms. However, in all of these approaches, the presence of Trichoderma did not influence the production of lipopeptides by B. velezensis and consequently its activity in biocontrol. The effect on the production of these NRPs is most noticeable in a minimal medium designed to impose a nutritional dependence between Bacillus and Trichoderma. The bacteria's requirement for a nitrogen source provided by T. harzianum, mainly in the form of peptides and amino acids, allows them to coexist in coculture. The physical presence of the fungus inhibits the production of lipopeptides, but the presence of its supernatant promotes it. The molecular dialogue between the Trichoderma - Bacillus couple needs to be further deciphered in order to exploit it in agricultural applications
Baudequin, Timothée. "Caractérisation biologique et mécanique d'un subsitut osseux biohybride et développement de scaffolds par électrospinning : vers un pansement vivant pour la reconstruction maxillo-faciale." Thesis, Compiègne, 2015. http://www.theses.fr/2015COMP2219/document.
Full textAn hybrid bone substitute, based on a specific biomaterial (scaffold) and living cells, was studied, developed with a tissue engineered method and characterized. It should meet the expectations of the maxillofacial surgery : a standard process which could fit with the complex geometries of each patient’s bone mass loss, a flexible shape with an easy handling, a prevascularization and a sufficient mechanical cohesion. A sheet-like shape was thus designed and developed in a specific flat cell culture chamber, with a monolayer of calcium phosphate granules as a scaffold. After both biological and mechanical full characterizations with a cell line, the process was adapted to a coculture of human primary cells (stem and endothelial cells). Relevant differentiation and prevascularization were highlighted but the mechanical cohesion could be noticed as too low to ensure an easy handling during the surgery. The last part of this thesis project was thus the set-up of a device for electrospun polymer fibers in order to use them as a new scaffold. The production of these materials was efficiently performed for several polymers. The differentiation potential for bone and tendon lineages was studied and compared to other scaffolds from national and international collaborations. The application of mechanical solicitations to the substitutes during cellculture was also studied
Martínez, González José Luis. "Utilisation de la coculture de Lactobacillus rhamnosus RW9595M et Lactobacillus rhamnosus R, pour moduler le poids moléculaire de leurs exopolysaccharides produits." Master's thesis, Université Laval, 2008. http://hdl.handle.net/20.500.11794/21139.
Full textUlmann, Lauriane. "Etude des interactions fonctionnelles entre neurones sensoriels des ganglions rachidiens et kératinocytes de l'épiderme : mise au point d'un modèle de coculture." Université Louis Pasteur (Strasbourg) (1971-2008), 2004. http://www.theses.fr/2004STR13213.
Full textA coculture model between sensory neurons of dorsal root ganglion and keratinocytes of epidermis of newborn rats and corresponding cell lines has been developed. Each cell type has been characterized by immunocytochemistry, electron microscopy and calcium imagery. The coculture needs a specific medium for keratinocytes, with a low calcium concentration (MCDB 20). In this medium, axons of neurons cultivated without keratinocytes don't appear, but the axonal growth is observed when the calcium concentration is increased to 2 mM. The presence of keratinocytes (cocultures) allows an important neuritic extension similar to this observed in the 2 mM calcium medium. This observation suggests that the target cells release some trophic factors which induce the axonal growth. After determining the neuronal phenotype in coculture, we have looked for the molecules implied in the trophic effect. The addition of NGF, BDNF or DHEA induces an important axonal extension. The presence of Trk receptors and BDNF in neurons, the decrease of the axons gowth in coculture with the Trk or PBR blokers, or with the addition of the DHEA synthesis enzyme shows that neurotrophins and DHEA are imply in the trophic effect of keratinocytes. On the other hand, the physical contacts observed with electron microscopy don't show any specific morphological differentiation. This coculture system allows the study of the effects of target cells on the neuronal development, the nature of trophics factors and the transmission of the sensory signal since the periphery
Lind, Marianne. "Etude des mécanismes de l'activation des cellules dendritiques par les lymphocytes T CD4+ chez l'homme." Paris 7, 2007. http://www.theses.fr/2007PA077120.
Full textDendritic cells (DCs) are the sentinels of the immune System. They allow the fast induction of appropriate adaptive responses. To do so, immature DCs need to be activated. The maturation of DCs is induced by microbial products and also by interactions of DCs with other cells of the immune System, such as CD4+ T cells. The mechanisms by which CD4+ T cells activate DCs are poorly understood. We thus decided to study CD4+ T cell-dependent signals that contribute to DC activation. We have shown, in a human model, that T cell-dependent DC activation is antigen-specific and depends on cell contacts through the transmembrane molecules CD40L and CD40. Moreover, the secretion of IL-12 and IFN-γ is crucial for the activation of DCs. We then observed that in the presence of CD4+ T cells and antigen, DCs undergo striking morphological changes and become motile. We have shown that chemokines produced during antigen-specific interactions between DCs and T cells induce cytoskeleton remodelling in DCs, which might allow their acquisition of migratory capacities. Finally, we tried to better characterize the soluble factors produced during antigen presentation. We observed that big amounts of IFN-γ and many other cytokines were produced, including chemokines. Interestingly, we showed that chemokines play a role in the production of IL-12 by DCs, in addition to their role in DC mobility. Our study shed some light on the mechanisms by which T cells, particularly via chemokines, influence key steps of DC maturation
Martinez, Gonzalez Jose Luis. "Utilisation de la coculture de Lactobacillus rhamnosus RW-9595M et Lactobacillus rhamnosus R, pour moduler le poids moléculaire de leurs exopolysaccharides produits." Thesis, Université Laval, 2008. http://www.theses.ulaval.ca/2008/25669/25669.pdf.
Full textThevenard, Benoît. "Implication des systèmes à deux composants dans les réponses de Streptococcus thermophilus à des changements environnementaux, dont la coculture avec Lactobacillus bulgaricus." Phd thesis, AgroParisTech, 2011. http://pastel.archives-ouvertes.fr/pastel-00734426.
Full textMoritz, Joseph M. (Joseph Michael). "Increased differentiation properties in two- and three-dimensional coculture of hepatocytes and liver epithelial cells by a novel quantitative functional liver assay." Thesis, Massachusetts Institute of Technology, 2007. http://hdl.handle.net/1721.1/39352.
Full textIncludes bibliographical references (leaves 100-121).
Hepatic stem cells in adult rats are activated by chemical injury to the liver, causing hepatic progenitor cells to proliferate, integrate into the hepatic plates, and differentiate into hepatocytes. In an attempt to model this process in vitro, we established and quantitatively assayed the differentiation properties of a strain of rat liver epithelial cells (LEC), lig8, grown in coculture with mature liver cells in a three dimensional, perfused microreactor optimized for hepatocyte culture. Lig8 was derived by suppression of the asymmetric growth kinetics that may be indicative of stem cells, and Lig8 progeny can be induced to exhibit several hepatocyte-specific differentiation properties in vitro; however, Lig8 full hepatocyte functional differentiation in culture has not yet been achieved. We hypothesized that more extensive differentiation properties may be observed in vitro if the Lig8 cells are cultured in an engineered analog of the 3D tissue environment that influences progenitor cell differentiation in vivo. We also assayed the differentiation properties of the hepatocytes in coculture. Previous studies have shown an increase in the differentiation of hepatocytes in 2D hepatocyte-LEC cocultures; we wished to determine if the benefit of coculture also occurs in the 3D microreactor.
(cont.) We therefore compared the differentiation properties of both cell types in 3D microreactor cocultures to three more traditional culture formats: 2D rigid collagen monolayer, 2D collagen gel sandwich, and 3D spheroids. To assess the functional differentiation state of both cell types in these cocultures, we implemented a cell-localizable quantitative assay for endocytotic uptake of fluorescent ligands of the hepatocyte asialoglycoprotein receptor (ASGPR). T'o additionally assay overall differentiation of the cultures, we examined the level of expression compared to in vivo of three hepatocyte-specific transcripts: ASGPR, and two highly abundant drug-metabolic enzymes CYP3A1 and CYP2E1. Of all the culture modes tested, three-dimensional microreactor coculture was shown to be the most highly differentiated by the fluorescent ligand uptake assay for ASGPR and CYP3A1, with near in vivo expression of CYP3A1. However, coculture only improved the expression of the transcripts for ASGPR and CYP2E1 in 2D rigid collagen monolayer cocultures. lig8 exhibited no uptake of the ASGPR-ligand in monoculture, but in all cocultures tested, rare cells were found positive, with a higher percentage of lig8 taking up the ligand in 31) than in 2D (although cell fusion was not ruled out).
(cont.) We conclude that this three-dimensional coculture system may be more physiological in vitro model for the study of LEC-mature cell interactions and liver response to carcinogens.
by Joseph M. Moritz.
Ph.D.
Ziegler, Elke [Verfasser], Carsten [Akademischer Betreuer] Gründker, and Matthias [Akademischer Betreuer] Dobbelstein. "Characterization of human breast cancer cells affected by coculture conditions and kisspeptin-10 / Elke Ziegler. Gutachter: Carsten Gründker ; Matthias Dobbelstein. Betreuer: Carsten Gründker." Göttingen : Niedersächsische Staats- und Universitätsbibliothek Göttingen, 2013. http://d-nb.info/1044414847/34.
Full textHakelius, Malin. "Interactions between Malignant Keratinocytes and Fibroblasts : Studies in Head and Neck Squamous Cell Carcinoma." Doctoral thesis, Uppsala universitet, Plastikkirurgi, 2014. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-221109.
Full textMEIGNEN, BRUNO. "Etude comparee des caracteristiques microbiologiques et biochimiques en milieu cerealier de l'association saccharomyces cerevisae - lactobacillus brevis en monoculture et en coculture ; interet organoleptique en panification." Nantes, 1998. http://www.theses.fr/1998NANT2004.
Full textWagner, Stéphanie. "Développement et caractérisation d'un nouveau système de coculture nerf-muscle permettant la différenciation tardive du muscle de Souris : étude morphologique, biochimique, fonctionnelle, enzymologique et électrophysiologique." Université Louis Pasteur (Strasbourg) (1971-2008), 2001. http://www.theses.fr/2001STR13138.
Full textAbd, Hadi. "Interaction between waterborne pathogenic bacteria and Acanthamoeba castellanii /." Stockholm, 2006. http://diss.kib.ki.se/2006/91-7140-569-0/.
Full textAlvarenga, Veronica Ortiz 1983. "Modelagem preditiva do crescimento/morte de Saccharomyces cerevisiae em co-cultura com Lactobacillus fermentum em mosto de caldo de cana-de-açucar." [s.n.], 2008. http://repositorio.unicamp.br/jspui/handle/REPOSIP/255403.
Full textDissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia de Alimentos
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Resumo: No Brasil e em outros países, a fermentação alcoólica é realizada sem esterilização do caldo de cana-de-açúcar que constitui um ótimo substrato para o crescimento microbiano tornando-se, assim, inevitável à presença de contaminantes. Estes apresentam-se como os principais responsáveis pela redução no rendimento e produtividade da fermentação. Esta pesquisa teve por objetivo predizer os parâmetros de crescimento (taxa de crescimento (m), tempo de adaptação (l) e população máxima (Rg)) da Saccharomyces cerevisiae e Lactobacillus fermentum, quando cultivados individualmente ou em co-cultura através da aplicação dos modelos primários de crescimento de Baranyi & Roberts (1994) e Gompertz modificado (Zwietering et al, 1991). Em função de variações de temperatura (28 ¿ 32ºC) e concentração de inóculo de L. fermentum (101 ¿108 UFC/mL), mantendo-se fixo o nível de inóculo de S. cerevisiae em 106 UFC/mL. Para a modelagem primária foi ajustado, também, o modelo quase-químico. Para a construção deste modelo, foi utilizado o software Matlab versão 7.5. A inoculação das culturas foi realizada em mosto de cana-de-açúcar clarificado industrialmente, e ajustado a 21.5ºBrix. O material foi tratado termicamente a 121ºC por 40 minutos e mantido congelado a ¿20ºC até a realização dos ensaios. Foram adicionados 200 mL de mosto, em elernmeyeres de 500mL esterilizados. Para o ajuste do inóculo da levedura foi realizada a contagem da suspensão em Câmara de Neubauer e para o lactobacilo o ajuste foi realizado com o auxílio do Densimat¿ (BioMérieux, S.A., France). Os ensaios de fermentação foram conduzidos em incubadora com agitação contínua de 120 rpm (New Brunswick Scientific, Model G-27, U.S.A.) e temperatura controlada. Para cada ensaio realizado com a cultura mista, foram conduzidos outros dois ensaios da mesma forma e com o mesmo substrato para as culturas puras de S.cerevisiae e L. fermentum. Os dados obtidos foram ajustados com o software DmFit para os modelos de Baranyi e Roberts (1994) e Gompertz modificado (Zwietering et al 1991). Não houve diferença significativa (p<0,10) para l, m e Rg da levedura e para l e m. No entanto, para Rg do lactobacilo houve diferença significativa entre a cultura pura e mista. Quando a levedura atinge a fase estacionária o lactobacilo teve sua taxa de crescimento incrementada de sua população máxima aumentou relevantemente no final da fase estacionária da levedura. O modelo de Baranyi e Roberts descreveu melhor a fase de adaptação dos microrganismos. Já o modelo quase-químico apesar de descrever crescimento/declínio não modela adequadamente o plateau da fase estacionária, quando ele acontece. O modelo secundário da população máxima do lactobacilo em função da temperatura de fermentação e nível de inóculo demonstrou que o nível de inóculo e sua interação com a temperatura foram significativos ao nível de 10% de significância. O índice de viabilidade da levedura pura foi afetada por mudanças na temperatura. Porém, para a cultura mista, com o tempo de fermentação fixo (21 horas) o nível de contaminaçao pelo lactobacilo foi altamente significante. O melhor indice de viabilidade foi observado para L=103UFC/mL e temperatura de fermentação a 25oC. Nas condições estudadas foi observado um máximo na produção de etanol quando a temperatura de fermentação foi 28oC e o nível de inóculo de lactobacilo de 105UFC/mL. O efeito quadrático da temperatura de fermentação foi mais significativo (p<0,10) que o nível de contaminação do lactobacilo na produção máxima de etanol. Os modelos determinados neste estudo poderão servir para posterior otimização de processos fermentativos na indústria sucroalcooleira
Abstract: In Brazil and other countries around the World, the sugar cane must fermentation for alcohol production is carried out without sterilization of the sugar cane juice, being an excellent medium for the multiplication of undesirable contaminants. Among the contaminants of sugar cane must, Lactobacillus fermentum can be considered one of the most relevant being able to cause the flocculation of yeasts and to reduce ethanol yield and productivity of the fermentation. This research aimed to predict the growth parameters lag time (l), specific growth rate (m) and maximum population (Rg) of Saccharomyces cerevisiae and Lactobacillus fermentum in individual and cocultures. Predictive modeling of microorganisms growth in co-culture and pure culture was done through the application of primary growth models of Baranyi and modified Gompertz, varying temperature (24 ¿ 32ºC) and inoculum concentration of L. fermentum (101 ¿ 108 CFU/mL) with a fixed inoculums level of S. cerevisiae (106 CFU/mL). For the primary modeling it was also, adjusted the quase-chemical model for the construction of this model Matlab software version 7.5 was used. The inoculation of the cultures was carried out in sugar cane must industrially clarified and adjusted to 21.5ºBrix, heat treated must (121ºC per 40 minutes) were inoculated with the yeast and lactobacilli, the adjustment of the inoculum was done respectively by counting the suspension in Neubauer chamber and Densimat (BioMérieux, S.a., France). For each assay carried out with the mixed culture, two others tests with pure culture were done for comparison of growth parameters. The fermentation assays were conducted in an incubator with continuous agitation (120rpm) (New Brunswick Scientific, Model G 27, U.S.A.) and controlled temperature. From the data obtained, the growth parameters were determined through the adjustment of the data with DMFIT software for Baranyi and Roberts and Modified Gompertz. No siginificant diference (p<0.10) was found for l,m and Rg for the yeast in pure culture neither for l and m for Lactobacillus fermentum, but for lactobacilli Rg was significantly different for pure a coculture. When the yeast reached the stationary phase the lactobacilli growth rate was increased and its stationary phase it was observed after ward. Baranyi and Roberts¿s model best described lag phase was expected. The quasichemical model even though it describes growth/decline it does not model the stationary plateau. The secondary model for the maximum population of the lactobacilli as function of fermentation temperature and inocullum level showed that this last variable was significant and its interaction with temperature (p< 0.10). For the pure culture temperature was significant on the viability index. But for mixed culture for a fixed fermentation time (21h) the lactobacilli level of contamination was highly significant. Best IV was observed for L=103UFC/mL and T=25oC. When the maximum ethanol production was modeled for T, L independent variables. The temperature was significant a maximum was observed at T=28oC, L=105UFC/mL. These two models are practical application for the alcoholic fermentation industry
Mestrado
Mestre em Ciência de Alimentos
Poisbeau, Pierrick. "Etude electrophysiologique des controles excitateurs et inhibiteurs au niveau des cellules du lobe intermediaire de l'hypophyse en culture primaire ou en coculture avec des neurones hypothalamiques." Université Louis Pasteur (Strasbourg) (1971-2008), 1996. http://www.theses.fr/1996STR13034.
Full textHittinger, Marius [Verfasser], and Claus-Michael [Akademischer Betreuer] Lehr. "Autologous coculture of primary human alveolar epithelial cells and macrophages for evaluating the safety and efficacy of novel inhalation pharmaceuticals / Marius Hittinger ; Betreuer: Claus-Michael Lehr." Saarbrücken : Saarländische Universitäts- und Landesbibliothek, 2017. http://d-nb.info/1127040006/34.
Full textLi, Na. "Expansion des cellules souches hématopoïétiques dans les systèmes de cocultures des cellules endothéliales et des cellules stromales." Nancy 1, 2005. http://www.theses.fr/2005NAN11320.
Full textKletting, Stephanie [Verfasser], and Claus-Michael [Akademischer Betreuer] Lehr. "A new cell line-based coculture model of the human air-blood barrier to evaluate the interaction with aerosolized drug carriers / Stephanie Kletting ; Betreuer: Claus-Michael Lehr." Saarbrücken : Saarländische Universitäts- und Landesbibliothek, 2016. http://d-nb.info/1114735035/34.
Full textArnold, Vincent. "Etude des interactions entre les cellules tueuses naturelles et les cellules dendritiques dans le cadre de l'infection par le VIH-1." Paris 7, 2010. http://www.theses.fr/2010PA077125.
Full textThe crosstalk between DC and NK is a critical issue of NK activation resulting in both effector functions and survival or proliferation of NK cells, as well as the expansion of resting NK cells. In turn, once activated, NK cells may induce DC maturation (mDC) or DC killing. There is an increasing body of in vivo evidence indicating that NK-DC interactions during the early phase of innate immunity can impact the quality and magnitude of the subsequent adaptive immune response. NK and DC are thought to play critical roles in the first phases of HIV infection. In this study, we examined changes in the NK cell repertoire and functions occurring in response to early interaction with HIVinfected DC, using an autologous in vitro NK/DC coculture System. We show that NK cell interaction with HIV-1-infected autologous monocyte-derived DC (MDDC) modulates NK receptor expression. In particular, expression of the CD85J receptor on NK cells was strongly down-regulated upon coculture with HIV-1-infected MDDC. We demonstrate that CD85J+ NK cells exert potent control of HIV-1 replication in single-round and productively HIV-1-infected MDDC, whereas CD85J- NK cells induce a modest and transient decrease of HIV-1 replication. HIV-1 suppression in MDCC by CD85J+ NK cells required cell-to-cell contact and did not appear mediated by cytotoxicity or by soluble factors. CD85J+ NK cell inhibition of HIV-1 replication in MDDC is mainly mediated by CD85J interaction with an unknown ligand (distinct from HLA class I molecules) preferentially expressed on HIV-1-infected MDDC. We were able to show that the CD85J receptor interacts with two calcium-binding proteins, S100A8/A9. We demonstrated that HIV infection of MDDC induce modulations of the overall S100A8/A9 distribution on the surface of MDDC, and potentially influence through CD85J ligation mechanism the anti-HIV activity of human NK cells. There is a relative paucity of information regarding NK cell function in adaptive immunity from clinical vaccine trials, as few vaccine studies have attempted to evaluate the non-specific, yet potentially clinically relevant, NK response to immunization and to identify markers of this innate response which, indeed, might be useful as correlates of protective immunity. We have shown that the HIV-1 recombinant MVA vaccine strain being tested is indeed capable of inducing DC presentation of the HIV antigens, as well as specifying a particular NK response rendering the cells more potent against HIV infection in vitro
Thévenoux, Anne. "Altération du métabolisme énergétique des astrocytes induite par des lymphocytes T activés par le rétrovirus HTLV-1 et répercussions sur le devenir oligodendrocytaire dans un modèle de coculture." Lyon 1, 2004. http://www.theses.fr/2004LYO10238.
Full textVarella, Larissa. "Estudo químico e estratégias para modular o metabolismo secundário de actinobactérias endofíticas." Universidade de São Paulo, 2015. http://www.teses.usp.br/teses/disponiveis/60/60138/tde-12052015-105200/.
Full textMicroorganisms are prolific sources of bioactive natural products. Several clinically important drugs have microbial origin, and most of the therapeutically used antibiotics are produced by actinobacteria, mainly from the genus Streptomyces. The multidrug resistance observed in pathogenic microorganisms and tumor cells lead to the need for new antibacterial and antitumor drugs . Endophytic actinobacteria have shown great potential in the search for bioactive natural products. This work describes the chemical study of two endophytic actinobacteria strains: Streptomyces sp. RTd 22 and Streptomyces sp RTD 31, isolated from Tithonia diversifolia roots. Active fractions in biological assays were further fractionated for identifying the bioactive compounds, which are: the macrolide antibiotics concanamycins (S31-1) and B (S31-2), anhydrous aglycones of concanamycins A (S31-3) and B (S31-4), all four produced by Streptomyces sp. RTd31, and the ionophore polyether grisorixin (S22-2), produced by Streptomyces sp. RTd22. The production of these bioactive compounds was monitored by UPLC-MS via the SIM mode. Concanamycins A and B had maximum production at 96 h, and grisorixin at 192 h. Other compounds identified by the dereplication of buthanolic extracts of both actinobacteria were the siderophore norcardamine (S31-7) and deoxy-nocardamine (S31-8), the siderophores desferrioxamine B (S31-9) was identified only in buthanolic extracts of Streptomyces sp RTd31. Experiments varying media and co-culture were tested to stimulate the biosynthesis of novel compounds, but nothing new was identified. By genome sequencing of Streptomyces sp RTd22 and antiSMASH analysis it was possible to verify the presence of several biosynthetic clusters in the genome of this strain. It was possible to identify the biosynthetic clusters of himastatin (S22-4) and its analogous compound coelichelin (S22-5); however, these compounds were not biosynthesized in the culture conditions used. The grisorixin biosynthetic cluster was determined, and homologous recombination was performed for deleting the analogue gene of nigericin flavin monooxygenase nigCI. Two mutants were obtained, and one of them was cultured for analyzing its metabolic profile by mass spectrometry. There was no production of grisorixin or its possible precursor by the mutant, but others compounds were produced.
Trescher, Karoline. "Cokulturtestsystem für die Untersuchung des Einflusses physikochemischer Eigenschaften von Copolymeren auf das Verhalten von Keratinozyten und Fibroblasten." Phd thesis, Universität Potsdam, 2012. http://opus.kobv.de/ubp/volltexte/2012/6291/.
Full textChemical and physical properties of polymers can influence various cell types, e.g. concerning adherence and functionality. For instance, the elasticity of a polymer can influence, which pulling force a cell can generate towards a substrate. According to the cell type, its behavior can be controlled by intracellular feedback mechanisms. The surface charge and/or hydrophilicity of a polymer initially influence the adsorption of ions, proteins and other molecules. In particular, the composition, density, and conformation of the adsorbed components mediate the cell-material interactions. Since different cell types present varying cell membrane associated proteins, sugars and lipids, it is assumed that polymer properties can induce cell specific effects. Polymers, which can regulate specific cell reactions, become more and more important for biotechnological uses and applications in the regenerative medicine. The isolation and culture of primary keratinocytes is still challenging and an adequate wound healing remains a clinical task. A polymer, which enables a preferential adherence of keratinocytes and induces a reduced adherence of dermal fibroblasts, would provide enormous advantages for keratinocyte culture systems as well as for wound dressings. To investigate the specific influence of certain polymer properties on primary human keratinocytes and fibroblasts, a cell culture system for mono- and coculture of both cell types was established. The test system was designed as a screening to investigate the influence of polymers with gradations of different properties on the cells. Thereby, the viability and density of adherent and not adhered cells, as well as the impairment of the cell membranes were analyzed in mono- and cocultures, and the selective adherence of keratinocytes in the coculture was evaluated using a specific immunocytochemical staining for keratin14 and vimentin. Furthermore, the deposition of extracellular matrix components and the secretion of soluble factors were analyzed for the elastic polymers. Since the elasticity of crosslinked poly(n-butylacrylate) (cPnBA) networks can be adjusted by the amount of the crosslinker, they were used as model polymers to investigate the influence of varying elasticity to the cells. On the less elastic cPnBA, the ratio of keratinocytes to fibroblasts was increased compared to the more elastic one. From these results, a slight cell selective effect can be assumed. Acrylonitrile-based copolymers were used as model polymers for the variation of surface charge and hydrophilicity, since their properties can be modified by the type and molar ratio of comonomers. By the variation of the molar ratio of positively charged comonomers (Methacrylic acid-2-aminoethylester hydrochloride (AEMA) and N-3-aminopropyl methacrylamide hydrochloride (APMA)), or a negatively charged comonomer (2-methyl-2-propene-1-sulfonic acid sodium salt (NaMAS)), the amount of positive or negative charges was modified. The hydrophilicity was increased by the molar ratio of the hydrophilic comonomer N-vinylpyrrolidone (NVP). With an increased molar ratio of the positively charged comonomer AEMA, a tendency towards a higher density of adherent keratinocytes could be shown, whereby, the density of adherent fibroblasts remained unaffected. With increasing molar ratios of the positively charged comonomer APMA, no differences between cell densities, viability or selectivity were detectable. Comparable to AEMA, a tendency towards improved keratinocyte adhesion could be shown with an increasing molar ratio of the negatively charged comonomer NaMAS. The increase of the hydrophilicity of the copolymers led to a reduced adherence and viability of the keratinocytes, as well as of the fibroblasts. In conclusion, a test system was established, which enables the evaluation of primary human keratinocytes and fibroblasts in contact with different polymers in monoculture, as well as in coculture. Furthermore, the present thesis shows that directed modifications of polymer properties influenced the adherence and viability of both cell types. The decrease of elasticity and the increase of the molar ratio of charged comonomers led to an increased keratinocyte adherence. Since the fibroblasts remained unaffected, slight cell selectivity was shown. By further increasing the stiffness or the amount of charged comonomers, further enhancement of this effect might be possible.
Denépoux, Stéphane. "Induction de mutations somatiques des gènes d'immunoglobuline dans les lymphocytes B humain in vitro." Lyon 1, 1998. http://www.theses.fr/1998LYO1T045.
Full textChebbo, Mohamad. "Rôle des plaquettes dans l’asthme sévère." Thesis, Aix-Marseille, 2022. http://www.theses.fr/2022AIXM0229.
Full textPlatelets are anucleate cells that play a role in hemostasis, thrombosis and immunity. They are also involved in the pathogenesis of some inflammatory disorders such as asthma. The aim of this work is to better understand the role of platelets in severe asthma by studying: 1) the transcriptome of circulating platelets from severe asthma patients and by evaluating the platelet expression, in these patients, of HLA-F, a molecule mobilized to the surface of different cell types after their activation. 2) the presence of platelets in the bronchi, and by modeling the interaction between platelets and bronchial epithelial cells in an in vitro coculture system. In the first part, I developed a platelet purification technique showing the need to remove residual leukocytes and erythrocytes that significantly alter the platelet transcriptome results. Then, I compared the platelet transcriptome from severe asthmatic patients with that of platelets from control subjects. I was able to show that the platelet transcriptome of severe asthmatic patients is different from that of controls. Simultaneously, I showed that HLA-F was more strongly expressed on the surface of platelets from severe asthma patients at steady state and that HLA-F could be mobilized to their surface following activation. In the second part, I was able to show the presence of platelets in the bronchial submucosa. In addition, the co-culture between bronchial epithelial cells and platelets allowed to demonstrate a secretion of the growth factor PDGF-BB by bronchial epithelial cells, specifically induced by activated platelets
Ahuja, Varun [Verfasser]. "Investigation of the sensitisation potential of various textile dyes using a biphasic mice local lymph node assay (LLNA) and an in vitro loose-fit coculture-based sensitisation assay (LCSA) / Varun Ahuja." Berlin : Freie Universität Berlin, 2010. http://d-nb.info/1024541894/34.
Full textSoma, Claire Emilienne. "Exploration dans le cadre de la reversion de la resistance multiple, d'un nouveau modele de coculture macrophages/cellules tumorales adapte a l'etude de la cytotoxicite des vecteurs colloidaux (doctorat : pharmacotechnie et biopharmacie)." Paris 11, 1999. http://www.theses.fr/1999PA114817.
Full textKoskela, von Sydow Anita. "Regulation of fibroblast activity by keratinocytes, TGF-β and IL-1α : studies in two- and three dimensional in vitro models." Doctoral thesis, Örebro universitet, Institutionen för medicinska vetenskaper, 2016. http://urn.kb.se/resolve?urn=urn:nbn:se:oru:diva-48225.
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