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Smart biomaterials for connective tissues regeneration
Hefka Blahnová, Veronika ; Filová, Eva (advisor) ; Maxová, Hana (referee) ; Motlík, Jan (referee)
Connective tissues are characterized by significant volume of extracellular matrix. Their main role is to provide a mechanical support and protection to other body organs. This thesis is focused on regeneration of bone, cartilage and osteochondral defect. In the experimental part we observed viability and differentiation of human mesenchymal stem cells. In vitro we evaluated the potential of PCL scaffold with addition of growth factors, bone xenograft with biomimetic peptides, collagen I composite with bioceramics and a titanium alloy with nanostructured surface. During following in vivo study, we implanted a cell-free scaffold made of PCL, calcium phosphate and IGF-1, bFGF, TGFβ1 and BMP-2 to osteochondral defect. Unfortunately, addition of growth factors resulted in pathological inflammatory process despite clear beneficial effect in vitro. Likewise, the biomimetic peptide sequences promoted osteogenic differentiation of human mesenchymal stem cells. Addition of certain bioceramics influenced the scaffold morphology in the manner of pore size. However, we did not observe any effect of the surface characteristics on cell behavior. The cells were influenced rather by certain material. On the other hand, surface modification of titanium scaffold by anodic oxidation revealed that the most suitable...
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Growth factors and other bioactive substances for osteogenic differentiation of mesenchymal stem cells
Blahnová, Veronika ; Rampichová, Michala (advisor) ; Vandrovcová, Marta (referee)
The main function of mesenchymal stem cells in the body is to facilitate the restoration and regeneration of damaged tissues. They are known for the ability to differentiate into tissue originating from the mesoderm, which among others includes connective tissues. Due to this feature are MSCs being intensively examined. Different directions of differentiation can be induced by treatment of specific polypeptides, so called growth factors. In the field of tissue engineering are growth factors used to induce and accelerate the healing processes. They may be incorporated into the nanofiber carrier which is inserted into the site of injury. Cells in this area would thus be stimulated by surrounding 3D microenvironment. At the same time the scaffold provides a supply of growth factors which are able to affect metabolism, motility and differentiation of present cells. In order to induce osteogenic differentiation of human MSCs the following bioactive substances were used: TGF-β, bFGF, HGF, IGF-1, VEGF and the BMP-2 and the organic acid taurine. During 21 days lasting experiments, were these molecules added to the medium in various combinations and in the case of taurine also at two different concentrations. Cells were cultured on plastic. The best effect on cellular metabolism of MSCs, evaluated by MTS...
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Effect of growth factors and bioactive substances on mesenchymal stem cell differentiation.
Blahnová, Veronika ; Daňková, Jana (advisor) ; Zajícová, Alena (referee)
Mesenchymal stem cells are a population of multipotent cells, which have the ability to restore damaged tissues derived from mesoderm. Under the influence of wide range of growth factors, hormones and other bioactive molecules they can differentiate for example into chondrocytes, osteocytes, adipocytes, myocytes or insulin producing cells. The differentiation is induced even by contacts with neighboring cells or with extracellular matrix. Tissue engineering often uses especially growth factors. Growth factors act through specific surface receptors, which mediate cell-to-cell and cell-to-extracelular matrix communication and influence many cellular processes such as growth, proliferation, differentiation and others. Due to their specific impact growth factors are used individually or in combinations in tissue engineering applications. Substances stimulating cells to proliferate and differentiate can be added right to the culture medium, when cultivated in vitro, or can be loaded into a scaffold onto which cells are later seeded. The determination of exact growth factors combinations and concentrations influence on MSCs differentiation would enable more efficient use of MSCs in regenerative medicine. The aim of this thesis is to summarise present knowledge about the effect of growth factors and other...
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