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The role of extracellular matrix in mesenchymal stem cell biology
Šimková, Zuzana ; Chudíčková, Milada (advisor) ; Hubálek Kalbáčová, Marie (referee)
The aim of this bachelor thesis is to describe the mutual relations of mesenchymal stem cells and extracellular matrix, their communication and to point out their significance in living body. First part is focused on description of extracellular matrix, its components and characteristics. The interaction between extracellular matrix and surrounding cells is using both receptors and enzymes. Second part addresses the description of mesenchymal stem cells which are crucial producers of extracellular matrix. The matrix is also decisive part of stem cells niche which envelopes them, protects them and decides their future. The last section demonstrates possible utilizations of differentiation potential and paracrine secretion of MSC in therapy and identifies some of the risks bound to it.
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Impact of mesenchymal stem cells on islets revascularization after transplantation into the extracellular matrix
Hudzieczková, Aneta ; Girman, Peter (advisor) ; Černý, Jan (referee)
Pancreatic transplantation is the only possible treatment to induce independence from exogenous insulin administration in type 1 diabetes mellitus. However, the shortage of donor organs remains the main limitation of pancreas transplantations. The goal of the research is the preparation of a bioartificial organ based on cell therapy. Parts of the extracellular matrix obtained by decellularization of the pancreas are used for its preparation. The protein scaffolds prepared in this way are then repopulated by different cell types again. The extracellular matrix provides structural support to cells, mediates signaling for differentiation, proliferation or migration. Mesenchymal stromal cells are used in clinical therapy, have a positive effect on tissue regeneration processes, modulating the function of the extracellular matrix, suppress inflammation and promote angiogenesis. After pancreas decellularization, we repopulated the extracellular matrix with islets, mesenchymal cells and endothelial cells. Then, the pancreas was transplanted subcutaneously into syngeneic diabetic rats to observe islet revascularization. Based on sections of explanted scaffolds, we found out that revascularization of the islets was higher without the endothelial cells in the transplanted extracellular matrix. Key words:...
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Role of sulfhydryl oxidase 1 in cancerogenesis
Beranová, Lea Marie ; Truksa, Jaroslav (advisor) ; Šuťák, Róbert (referee)
Disulfide bridges play a significant role in protein-folding as well as en- zyme activity and thus regulate many intra- and extracellular processes. Sulfhydryl oxidase QSOX1 forms S-S bridges de novo, modulating the activity of its substrates and thus directly or indirectly influences vital cel- lular processes. The first part of this thesis focuses on characterization of the role of QSOX1 in cancerogenesis, using breast cancer cell lines (MCF7, MDA-MB-231) and pancreatic cancer cell line (Panc-1), while the second part emphasizes the regulation of QSOX1 expression by different oxygen concentrations. To study the effect of QSOX1 on proliferation of triple-negative cancer cells MDA-MB-231, two genetically modified cell lines - QSOX1-overexpressing and QSOX1 knockout cell lines - were constructed. While increased QSOX1 protein levels do not have a significant effect, the absence of QSOX1 leads to a decreased cellular growth. Lack of QSOX1 also results in visible change in cellular morphology. QSOX1 knockout cells can be mostly characterized as more round-shaped with less noticeable or completely missing lamellipo- dia. This finding is with agreement with to-date literature suggesting that QSOX1 is important not only for cellular proliferation but also for migration and invasiveness. While authenticating the theory of...
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Study of mesenchymal stem cell migration in the extracellular matrix based on principles of chemotaxis
Scholasterová, Viktorie ; Fohlerová, Zdenka (referee) ; Chmelíková, Larisa (advisor)
This thesis engages in a study of mesenchymal stem cell migration in extracellular matrix based on principles of chemotaxis. First, attention is focused on a theoretical part associated with a clarification of basic terms such as extracellular matrix, migration, confocal microscopy, mesenchymal stem cells or chemotaxis. There is also included a list and a description of some basic methods for monitoring cell migration and a more detailed description of a method called transwell assay, which has been chosen for an experiment in a practical part of this thesis. This part includes protocols of individual steps for the preparation of the experiment, the procedure of data processing obtained by scanning cells with a confocal microscope and a description of the resulting confluence values.
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Development of extracellular-matrix scaffolds for CNS repair
Výborný, Karel ; Kubinová, Šárka (advisor) ; Hampl, Aleš (referee) ; Vandrovcová, Marta (referee)
Výborný, Karel. Vývoj materiálů na bázi extracelulární matrix pro léčbu centrálního nervového systému. [Development of extracellular-matrix scaffolds for CNS repair]. Praha, 2020. 105 stran, 3 přílohy. Dizertační práce (Ph.D.). Univerzita Karlova, 2. lékařská fakulta, Ústav experimentální medicíny, AV ČR v.v.i. Abstract Brain and spinal cord injury are a serious traumata and despite intensive research, there is still no effective treatment for patients. One of the studied approaches is to use various biomaterials to repair the damaged neural tissue. The aim of this thesis is to study the regenerative and neurotrophic effects of injectable extracellular matrix (ECM) hydrogels prepared by decellularization from porcine tissue (brain, spinal cord, bladder) and human umbilical cord (UC) in reconstruction of damaged neural tissue of the brain and spinal cord in rats. We characterized ECM hydrogels in terms of mechanical and rheological properties, structure and composition, cell adhesion, migration and proliferation. In a model of spinal cord hemisection, we compared the regenerative effect of ECM hydrogels derived from porcine spinal cord and urinary bladder. We found no benefits of tissue specific ECM prepared from the tissue of neural origin in terms of its neurotrophic properties in vitro or in vivo....
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Natural biomaterials and mesenchymal stem cells in regeneration of spinal cord injury
Kekulová, Kristýna ; Kubinová, Šárka (advisor) ; Krulová, Magdaléna (referee) ; Filová, Elena (referee)
Spinal cord injury is a serious trauma and despite intensive research there is still no effective treatment for patients. The aim of this thesis is to study new possibilities of spinal cord injury therapy in animal models. We have focused on the use of natural materials, stem cells, gene therapy and the possibility of combining these approaches. The effect of extracellular matrix (ECM) based materials prepared by decellularization of porcine spinal cord and porcine urinary bladder on tissue regeneration after acute hemisection of the spinal cord was investigated. Another tested material was a hydrogel based on hyaluronic acid modified with RGD adhesion peptide, which was applied acutely and subacutely into the hemisection lesion. We have shown that both types of biomaterials have positive effect on regeneration of the spinal cord tissue by bridging the lesion and promotion of axonal ingrowth. In addition, ECM hydrogels promote the growth of blood vessels into the lesion site. The combination of hydrogels with mesenchymal stem cells derived from human umbilical cord (hWJ-MSCs) had synergistic effect, but since only a limited number of cells could be incorporated into hydrogels, this effect was not associated with improvement in motor skills. The limitation of ECM hydrogels is their rapid...
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Monitoring of mesenchymal stem cell migration in the extracellular matrix
Zumberg, Inna ; Čmiel, Vratislav (referee) ; Chmelíková, Larisa (advisor)
This master’s thesis contains a description of mesenchymal stem cells (MSC). The work includes knowledge about the process of migration and differentiation of MSCs. The theoretical part of this thesis also deals with the problem of cell cultivation in 2D and 3D environments. The most used materials for creating 3D scaffolds are described here. The practical part contains the description of the cell culture protocol for passaging and also describes the experiment in the cell laboratory. The results of the experiment are discussed using confocal microscope images. The proposed experiment was tested with a sufficient number of repetitions. The processing of microscopic images was performed in the MATLAB programming environment.
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Role of sulfhydryl oxidase 1 in cancerogenesis
Beranová, Lea Marie ; Truksa, Jaroslav (advisor) ; Šuťák, Róbert (referee)
Disulfide bridges play a significant role in protein-folding as well as en- zyme activity and thus regulate many intra- and extracellular processes. Sulfhydryl oxidase QSOX1 forms S-S bridges de novo, modulating the activity of its substrates and thus directly or indirectly influences vital cel- lular processes. The first part of this thesis focuses on characterization of the role of QSOX1 in cancerogenesis, using breast cancer cell lines (MCF7, MDA-MB-231) and pancreatic cancer cell line (Panc-1), while the second part emphasizes the regulation of QSOX1 expression by different oxygen concentrations. To study the effect of QSOX1 on proliferation of triple-negative cancer cells MDA-MB-231, two genetically modified cell lines - QSOX1-overexpressing and QSOX1 knockout cell lines - were constructed. While increased QSOX1 protein levels do not have a significant effect, the absence of QSOX1 leads to a decreased cellular growth. Lack of QSOX1 also results in visible change in cellular morphology. QSOX1 knockout cells can be mostly characterized as more round-shaped with less noticeable or completely missing lamellipo- dia. This finding is with agreement with to-date literature suggesting that QSOX1 is important not only for cellular proliferation but also for migration and invasiveness. While authenticating the theory of...
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Studies of intercellular interactions in tumours
Jechová, Alžběta ; Smetana, Karel (advisor) ; Skalníková, Helena (referee) ; Masařík, Michal (referee)
Beside tumor cells themselves, tumors consist of many non-malignantly transformed cellular elements and an extracellular matrix. This so-called tumor microenvironment, or stroma, significantly influences the biological properties of the tumor through intercellular interactions. In this thesis I have focused on the study of tumor-associated fibroblasts in squamous cell carcinomas of the head and neck, malignant melanoma and glioblastoma. The data show the presence of cells with mesenchymal characteristics, present even in the glioblastoma stroma, which could potentially have a positive effect on proliferative activity and invasiveness of glioblastoma cells. In malignant melanoma, the presence of keratinocytes should also be considered, as they are the major cells of the epidermis influencing tumor melanocytes. The conditioned medium from UVB irradiated keratinocytes and non-irradiated fibroblasts stimulates the invasion of malignant melanoma cells. Targeting the tumor stroma may be a new direction in oncological therapy, so we have focused on the influence of synthetic polyamine on the formation of myofibroblasts, which are an active part of the population of tumor-associated fibroblasts. The tested polyamine prevents the formation of myofibroblasts but has no effect on those already formed nor on...
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Mesenchymal stromal cells and biological scaffolds for neural tissue regeneration
Kočí, Zuzana ; Kubinová, Šárka (advisor) ; Filová, Eva (referee) ; Zach, Petr (referee)
Despite tremendous progress in medicine, injuries of the adult central neural system remain without satisfactory solution. Regenerative medicine employs tissue engineering, cellular therapies, medical devices, gene therapy, or growth factors with the aim to bridge the lesion, re-establish lost connections and enhance endogenous repair in order to restore neural function. The aim of my thesis was to evaluate therapeutic potential of two approaches, transplantation of human mesenchymal stromal cells (hMSCs) and biological scaffolds derived from extracellular matrix (ECM) for neural regeneration, particularly in models of spinal cord injury (SCI). First, hMSCs from various sources - bone marrow (BM), adipose tissue (AT) and Wharton's jelly (WJ) - were isolated and characterized in vitro. All cell types met the minimal criteria for MSC phenotype and displayed similar properties in terms of their surface marker expression, differentiation potential, migratory capacity, and secretion of cytokines and growth factors. On the other hand, the cell yield from WJ and AT was significantly higher, and MSCs isolated from these tissues proliferated better than from BM. Therapeutic effect of intrathecal application of hWJ-MSCs was then evaluated in SCI compression model in rats. The effect of low (0.5 million) and...
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