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Immunomodulatory and differentiation properties of MSCs in a mouse model of the injured cornea and retina
Kössl, Jan ; Holáň, Vladimír (advisor) ; Vištejnová, Lucie (referee) ; Heissigerová, Jarmila (referee)
Stem cells, in general, represent the potential for treating many diseases and disorders that are currently difficult to treat or the therapy has many side effects. One of the stem cells widely investigated these days are mesenchymal stem cells (MSCs). MSCs have the considerable immunomodulatory and regenerative potential for treating degenerative disorders and severe damage to various parts of the eye or other organs. Likewise, their application could serve as supportive therapy in corneal transplantation and other eye inflammatory conditions. In this study of immunomodulatory properties of MSCs, we have focused mainly on their ability to differentiate into cells of different tissue types (in our case, corneal epithelium and retina), their production of immunomodulatory molecules in the inflammatory environment, their ability to migrate to the site of the injury, and their local anti-inflammatory, regenerative, and anti-apoptotic effects. In addition, we tested the therapeutic effects of MSCs in a mouse model of ocular surface injury and a model of retinal degeneration. Finally, we investigated the mechanism of this effect in in vitro models with explants of these tissues. Limbal stem cells (LSCs) are already used to treat severe corneal damage as limbal stem cell deficiency. However, this...
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The role of innate lymphoid cells in influenza virus infection
Mouyabi, Flaviancia ; Hrdý, Jiří (advisor) ; Kössl, Jan (referee)
Innate lymphoid cells (ILCs) are recently discovered group of innate immune cells. They do not have antigen-specific receptors but they can be activated by cytokines similarly to T lymphocytes. ILCs have a crucial role in the regulation of inflammation, tissue repair, containment of commensals, anti-infection immunity and regulation of tissue homeostasis. The presence of mouse and human ILCs can be detected in the lung during and after influenza virus infection when ILCs contribute to the restoration of damaged lung parenchyma. ILCs directly or indirectly provide protection against viral infections by secretion of various cytokines and co-operation with other cells (e.g. T cells, macrophages). Overall, lung ILCs are important in immune responses and tissue homeostasis, but further studies on this topic are needed to fully understand their role. The aim of this thesis was to specifically characterize these cells, focus on their function in the lung, and describe their role in the course of influenza virus infection.
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Functionalized chitosan-based nanofibres for accelerated regeneration of soft tissues
Bazikov, Philipp ; Filová, Eva (advisor) ; Kössl, Jan (referee)
To improve the regeneration of soft tissues, wound dressings were developed, containing nanofibers, different in composition and functional features. The work concentrates on chitosan and composite scaffolds containing chitosan. Porous nanofibre materials based on chitosan are very promising for the regeneration of soft tissues. Chitosan exhibits pH-sensitive behavior due to the large number of amino groups on its chains, which makes chitosan nanofibres promising carriers for the delivery of drugs. In this work, the examples of different modifications of nanofibres are shown. To increase the efficiency and accelerate the regeneration of soft tissues, nanofibres are functionalized with bioactive substances of various types: antimicrobial, analgesic, growth factors, etc. To stabilize nanofibres and to improve the physical characteristics, treatments using glutaraldehyde, glyoxal, genipin or heat treatment were used. Chitosan is used to inhibit fibroplasia during wound healing and to promote cell growth and differentiation. The efficiency of antibacterial activity of chitin-glucan complex with nanofibres for wound healing was shown. Reconstruction of deeper wounds, in which skin and soft tissues are damaged, requires measures for spatial reconstruction and stimulation of regeneration processes in the...
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Use of the nanofiber scaffold for transfer of stem cells onto the injured ocular surface in mouse experimental model
Kössl, Jan ; Zajícová, Alena ; Heřmánková, Barbora ; Javorková, Eliška ; Boháčová, Pavla ; Holáň, Vladimír
Corneal damage is one of the most common causes of impaired vision or even blindness. When the injury is more extensive and the limbal region is involved, the natural regeneration of the cornea is not sufficient. Such damage can lead to the limbal stem cell deficiency (LSCD). The only option for LSCD treatment is transplantation of the limbal tissue or a transfer of limbal stem cells (LSCs) cultured from the healthy eye. The allogenic transplantation of the limbus or cultivated LSCs with a systemic administration of immunosuppressive drugs is needed in the case of bilateral LSCD. Nevertheless, the cell therapy is very promising approach for LSCD treatment. Transplantation of mesenchymal stem cells (MSCs) seeded on an appropriate scaffold turned out to be a suitable therapy of the LSCD. In our experimental model of LSCD we use nanofiber scaffold for MSC and LSC cultivation and for transplantation of these cells onto the chemically injured mouse eye. MSCs have immunosuppressive and immunomodulatory properties. We showed that MSCs have the ability to inhibit production of molecules associated with the inflammation and support epithelial regeneration in the damaged cornea. These inhibitory properties were confirmed in both in vitro and in vivo mouse model. Results thus showed beneficial effects of stem cell transplantation for murine corneal healing and for suppression of a local immune reaction which can impede the healing process. Such similarity of in vivo and in vitro results allows us further experiments to clarify mechanisms of MSC regenerative and healing properties after the transplantation onto the injured cornea.
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Nanofiber scaffolds for local delivery of stem cells and immunosuppressive drugs for therapeutic purposes
Zajícová, Alena ; Kössl, Jan ; Heřmánková, Barbora ; Boháčová, Pavla ; Holáň, Vladimír
Cell-based therapy of local tissue injuries or damages requires application of stem cells and inhibition of harmful inflammatory reaction which could impede the healing process. To increase the effectiveness of this therapy, a local administration of drugs can avoid their side effects associated with a systemic treatment. A local therapy requires suitable carriers, which can transfer the cells and drugs to the site of injury. As a promising carriers turned out nanofiber scaffolds prepared by electrospinning technology from various types of polymers. The main advantage of this technology is a possibility to define properties of nanofiber scaffolds, optimal for the growth and transfer of stem cells, and which could incorporate various types of immunosuppressive drugs. Here we describe the formation and use of nanofiber scaffolds prepared by needleless electrospinning technology from poly (L-lactic acid) (PLA) which are loaded with immunosuppressive drug Cyclosporine A (CsA). We show that CsA-loaded nanofibers effectively and selectively inhibit proliferation of activated T cells and suppress the production of T cell cytokines in vitro. Simultaneously, these nanofiber scaffolds enable growth of mesenchymal stem cells (MSCs) and thus can serve as stem cell carriers. Moreover, using an experimental mouse model of skin transplantation, we showed that covering skin allografts with MSC-seeded and CsA-loaded nanofibers significantly inhibited the local production of pro-inflammatory cytokines IL-2, IL-17 and IFN-gamma, and supported healing. Thus, nanofiber scaffolds seeded with stem cells and loaded with CsA can serve as carriers of cells and drugs for a local cell therapy and for simultaneous effective immunosuppression.
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Pro-apoptotic and anti-apoptotic properties of mesenchymal stem cells
Benešová, Iva ; Kössl, Jan (advisor) ; Anděra, Ladislav (referee)
Mesenchymal stem cells (MSC) display different ways of influencing not only surroundig cells but also the function of the whole organism. Besides well known immunomodulatory properties, MSC are capable of inducing and inhibiting of apoptosis in various conditions, effecting mostly cancer and immune cells. They are able to protect other cell types against apoptosis. On the contrary, anti-apoptotic and apoptotic effect of MSC is not always beneficial. Deeper and more precise understanding of influence of MSC on the apoptosis is needed to allow the usage of MSC in the biological therapy and to facilitate the treatment of many diseases. MSC are exhibited to oxidative stress, hypoxia and many pro-apoptotic factors, which cause their senescence and apoptosis. However, without this microenvironment they will not be activated and will not gain all their properties. Nowadays is an intensive research in prolongation of MSC's lifespan done, because it would improve potential biological therapy. Key words: mesenchymal stem cells, apoptosis, biological therapy
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The role of innate lymphoid cells in influenza virus infection
Mouyabi, Flaviancia ; Hrdý, Jiří (advisor) ; Kössl, Jan (referee)
Innate lymphoid cells (ILCs) are recently discovered group of innate immune cells. They do not have antigen-specific receptors but they can be activated by cytokines similarly to T lymphocytes. ILCs have a crucial role in the regulation of inflammation, tissue repair, containment of commensals, anti-infection immunity and regulation of tissue homeostasis. The presence of mouse and human ILCs can be detected in the lung during and after influenza virus infection when ILCs contribute to the restoration of damaged lung parenchyma. ILCs directly or indirectly provide protection against viral infections by secretion of various cytokines and co-operation with other cells (e.g. T cells, macrophages). Overall, lung ILCs are important in immune responses and tissue homeostasis, but further studies on this topic are needed to fully understand their role. The aim of this thesis was to specifically characterize these cells, focus on their function in the lung, and describe their role in the course of influenza virus infection.
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Local production of cytokines after treatment with stem cells of damaged ocular surface
Kössl, Jan ; Holáň, Vladimír (advisor) ; Kovář, Marek (referee)
The damage of ocular surface represents one of the most common causes of decreased quality of vision or even blindness. If the injury is extensive and includes the region of limbus, niche of limbal stem cells (LSC), LSC deficiency occurs and the natural corneal regeneration is stopped. Conjunctival epithelium migrates into the injured area. Neovascularization, local inflammation and corneal opacity occur. Corneal transplantation is an insufficient treatment in such case. If the injury is bilateral, the allogenic limbal graft or LSC transplantation is required. In such cases systemic immunosuppressive drugs with many negative side-effects must be administered. The search for an adequate autologous substitution is important for avoid immunosuppressive medication. Mesenchymal stem cells (MSC) represent a perspective substitution for the reason of their immunomodulatory properties and the capability to differentiate in many cell types. There is possibility to isolate sufficient number of these cells from adipose tissue or bone marrow which are relatively easily accessible. Our goal was to observe local production of cytokines and other molecules which are present in inflammatory reaction after the chemical burn of the murine cornea and after the treatment with stem cells growing on nanofiber scaffold....
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Possibilities of using stem cells for treatment of ocular surface injuries
Kössl, Jan ; Holáň, Vladimír (advisor) ; Drbal, Karel (referee)
Ocular surface defects are one of the most common causes of impaired vision or even blindness. Corneal transplantation is the first choice of the treatment of these defects. If the damage is extensive and includes the limbus, niche of limbal stem cells (LSCs), LSC deficiency (LSCD) occurs and reparation with regeneration of cornea is impaired. The only way to treat LSCD is limbal transplantation or transplantation of autologous LSCs from the healthy eye. In cases of bilateral LSCD there are no autologous LSCs available. The use of allogeneic LSCs is associated with the requirement of systemic or local administration of immunosuppressive drugs which have often negative side-effects and outcomes remain uncertain. The alternative for treatment of ocular surface defects and LSCD is finding a new source of an appropriate autologous stem cell substitute which are e.g. mesenchymal stem cells (MSCs). These cells can be obtained from bone marrow or adipose tissue of the particular patient. MSCs can be easily cultivated ex vivo and can be transferred onto the damaged ocular surface using appropriate scaffold. Here they can differentiate to corneal epithelial cells, have immunomodulatory properties and produce numerous trophic and growth factors. The experiments with MSCs on animal models of mechanically or...
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Josef Ladislav Píč (The Influence of special Disputs for his private and social Life)
KÖSSL, Jan
The thesis is lined in chronological sequence and dividend into six part, its titles are development of science in 19th century {--} history of archeologic research, childhood and adolescence, looking for the vocational integration, the science activity, special disputes, the meaning of publication and legacy Josef Ladislav Píč. The first part is divoted to the history of archeology by its diffident beginnings to its conversion into the real science. The second part treats of birth of Josef Ladislav Píč in 1847, his childhood in Mšeno, Česká Lípa and the years during his grammar schoul attendance in Prague and formation of his ideas. The next part is divoted to the adulthood of Píč and looking for his social enlistment. In the 5th part it is written about his individual science activity. The last but one chapter records his long-term science disputs, which leaded into his early death. The final part sums up his contribution to the science and the legacy of his life´s work.
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