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Human multipotent mesenchymal stromal cells - bone differentiation and hematopoietic support
Pytlík, Robert ; Trněný, Marek (advisor) ; Filová, Elena (referee) ; Lesný, Petr (referee)
Human mesenchymal stromal cells (hMSC) are adult stem or progenitor cells, which physiological role is reparation of damaged tissues. This is achieved mostly by secretion of trophic, angiopoietic and immunomodulatory factors. Beside this, hMSC have potential to differentiate in vitro into specialized cells, especially of the mesodermal lineages. Human MSC also significantly support hematopoiesis in hematopoietic niche. This knowledge raised high hopes for therapeutic use of hMSC, especially in regenerative medicine and treatment of autoimmune diseases, including graft versus host disease (GvHD). As a proof of concept served initially crude preparations of bone marrow mononuclear cells (BMMC), which contain small numbers of hMSC. In our hospital, two pilot clinical studies with BMMC were performed: study of treatment of acute myocardial infarction (negative, prematurely terminated) and study of treatment of peripheral leg arthery disease (promising results). Further research was aimed on optimalisation of hMSC cultivation method for clinical use to obtain highest possible yield and get free from animal proteins. Human MSC were traditionally cultivated in research-grade media with fetal calf serum (FCS), which can lead to immunization of patients after repeated application of hMSC. We achieved...
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Effect of the peptides on osteogenic differentiation of mesenchymal steam cells
Lukášová, Věra ; Amler, Evžen (advisor) ; Filová, Elena (referee)
Osteogenic differentiation of mesenchymal stem cells (MSCs) would be possible to induce by creating of a cell bioactive scaffold that mimic the properties of bone extracellular matrix (ECM). This induction will be not only due to the addition of osteogenic supplements, but also due to the addition of differentiation peptides. These peptides activate signaling pathways leading to cell differentiation. The aim of this study was to evaluate the effect of selected peptides on adhesion, metabolic activity, proliferation and osteogenic differentiation of porcine MSCs. Four peptides with amino acid sequences of DGEA, IAGVGGEKSGGF, GQGFSYPYKAVFSTQ and KIPKASSVPTELSAISTLYL were selected. These peptides were derived from receptor binding sequences of collagen I, collagen III, BMP-7 and BMP-2 respectively. Scaffolds were prepared from a biocompatible and biodegradable poly-ε-caprolactone (PCL) polymer, suitable for cell cultivation. Cells were cultured on scaffolds for three weeks. Various concentration of differentiation peptides were added to the culture medium. As observed in the experiment of cells cultured in basal medium supplemented with differentiation peptides no effect on adhesion, proliferation or metabolic activity of porcine MSCs was observed. In groups treated with peptides derived from BMP-2...
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Biomimetic modifications of titanium in bone tissue engineering.
Krýslová, Markéta ; Filová, Elena (advisor) ; Rampichová, Michala (referee)
When the big joints like a knee or hip joint are damaged, the solution of this problem is an artificial substitute. The replacement of damaged joints with endoprotesis helps to reduce the pain and to move normally. In the design of the implant is necessary to fulfil all requirements on the properties of the material. The surface of implant is important, because it is directly connected to bone tissue. After implantation, the negative effect include infection, inflammation or release of the implant due to limited osseointegration, may appear. The osseointegration can be improved by modifying the material surface. This thesis is focused on development and evaluation of advanced materials imitating the bone structure, especially nanoroughness and the presence of biomimetic component, such as hydroxyapatite. In this study is evaluated adhesion, proliferation, viability, differentiation, and synthesis of specific proteins of human osteoblasts like Saos-2 on titanium modified with nanotubes and plasma sprayed hydroxyapatite compared with smooth surfaces. Key words: titanium, nanotubes, osteoblasts, hydroxyapatite, nanoroughness
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Growth of human osteoblasts SaOS2 on titanium modified with nanotubes.
Krýslová, Markéta ; Filová, Elena (advisor) ; Melkes, Barbora (referee)
This work summarizes information about the interactions between osteoblasts and nanostructured materials, which are of growing importance and are highly promising in regard to their application in medicine and in tissue engineering. The number of people with artificial replacements of tissues, such as bones, joints, teeth, cartilage, and tendons increases every year. Titanium and his alloys are extensively used for artificial tissue replacements. Titanium is favourable for its mechanical properties that allow the implant to remain in the place of implantation more than thirty years. For better osseointegration the surface of titanium can be modified with hydroxyapatite, coating with diamond-like carbon or plasma spray coating. Another option is to prepare a layer of nanotubes, which forms nanoroughness on material surface. The nanoroughness in turn improves physical and chemical properties of the material surface. Nanostructured materials mimic the natural bone tissue, support adsorption of specific proteins, improve the biocompatibility of the implants and positively influence cell behaviour, e.g. stimulate the synthesis and suitable conformation of specific molecules for cell adhesion and differentiation.
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Adhesion, growth and potential immune activation of cells on metallic materials for bone implants.
Straňavová, Lucia ; Bačáková, Lucie (advisor) ; Filová, Elena (referee)
The contemporary orthopaedics and traumatology of the musculoskeletal system and stomatology have been witnessing a substantial increase in the number of surgeries using metallic implants. The issue of reconstruction of bone defects covers a large area of study, where the surface properties of the implants are extremely important. Bone defects often occur as a result of open fractures, radical cancer treatment or limb lengthening, which is very common in paediatric orthopaedics. In the treatment of these conditions, the surface of the applied materials should provide a favorable environment for bone cells and support bone formation. In endoprosthetics it is highly desirable to achieve the strongest possible fixation between the implant surface and the bone. During the surgery, primary stability of the implant fixation is ensured by the proper positioning of the implant, based on the appropriate shape of the implant and the quality of bone cut. The initial stability is only temporary, being estimated to last approximately three months. After this period, the secondary stability starts, determined by the bone ingrowth into the implant surface structure. Osteogenic differentiation and extracellular matrix (ECM) mineralization can be enhanced by the presence of bone morphogenetic proteins (BMPs),...
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Vascular and osseous cells in polymer structures for tissue engineering
Filová, Elena ; Bačáková, Lucie (advisor) ; Maxová, Hana (referee) ; Motlík, Jan (referee) ; Kromka, Alexander (referee)
Artificial vascular and bone prostheses are engineered as bioinert, not allowing cell attachment and growth. Our aim was to prepare materials based on natural and synthetic polymers that could modify the surface or create the bulk material of prostheses, and test their bioactivity in vitro. We prepared fibrin assemblies of various thicknesses and evaluated the adhesion, growth and differentiation of endothelial cells (EC) on these layers. We observed increased cell spreading on twodimensional fibrin assemblies and improved cell growth and maturation on thick fibrin gels. Fibrin coated with collagen I, or fibronectin, increased the adhesion area and the proliferation activity of vascular smooth muscle cells (VSMC). Synthetic polymers were based on an inert block copolymer of poly(DL-lactide) and polyethylene oxide (PDLLA-b-PEO) in which 5% or 20% of the PEO chains were grafted with Gly-Arg-Gly-Asp-Ser-Gly oligopeptide, a ligand for cell adhesion receptors. Grafting oligopeptide peptide to the cell non-adhesive copolymer restored adhesion and growth of VSMC, even in a serum-free medium. Synthetic polymers could therefore serve as artificial extracellular matrix analogues for vascular tissue repair and regeneration. Our study with human osteoblast-like MG 63 cells cultured in poly(lactic-co-glycolic acid)...
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