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Coaxial and emulsion nanofibers for biomedical use
Korbelová, Gabriela ; Buzgo, Matej (advisor) ; Pavlů, Barbora (referee)
The current treatment of tissue injuries deal with numerous problems, such as limited healing capacity and immune response of the body. In many cases such obstacles does not allow a full regeneration of the injured tissues and the full resumption of its original features. Controlled delivery of growth factors has considerable importance for inducing wound healing for a wide range of defects. Biocompatible and biodegradable nanofibrous carriers prepared by electrospinning represent a universal platform for the delivery of a wide range of substances in regulated manner. The goal of this thesis is to create an overview and assessment of the nanofibrous systems for controlled drug release created by electrospinning with a focus on growth factors delivery. Nanofiber carrier offers a number of advantages, they are able to consistently deliver bioactive substance into the site of injury, maintain bioactivity of the substance and stimulate the adhesion, proliferation and differentiation of target cells. Compared to the classic methods of tissue engineering using tissue grafts with the risk of their immune rejection these funkcionalized biodegradable carriers offers the possibility to create cell-free carrier systems. The work is divided into 4 chapters concerning the methods of preparation of nanofibrous...
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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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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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Coaxial and emulsion nanofibers for biomedical use
Korbelová, Gabriela ; Buzgo, Matej (advisor) ; Pavlů, Barbora (referee)
The current treatment of tissue injuries deal with numerous problems, such as limited healing capacity and immune response of the body. In many cases such obstacles does not allow a full regeneration of the injured tissues and the full resumption of its original features. Controlled delivery of growth factors has considerable importance for inducing wound healing for a wide range of defects. Biocompatible and biodegradable nanofibrous carriers prepared by electrospinning represent a universal platform for the delivery of a wide range of substances in regulated manner. The goal of this thesis is to create an overview and assessment of the nanofibrous systems for controlled drug release created by electrospinning with a focus on growth factors delivery. Nanofiber carrier offers a number of advantages, they are able to consistently deliver bioactive substance into the site of injury, maintain bioactivity of the substance and stimulate the adhesion, proliferation and differentiation of target cells. Compared to the classic methods of tissue engineering using tissue grafts with the risk of their immune rejection these funkcionalized biodegradable carriers offers the possibility to create cell-free carrier systems. The work is divided into 4 chapters concerning the methods of preparation of nanofibrous...
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Methodological detection solution scaffolds response to mechanical stress, depending on the degree of hydration
Mejzlíková, Kateřina ; Jelen, Karel (advisor) ; Kubový, Petr (referee)
Title: Methodological detection solution scaffolds response to mechanical stress, depending on the degree of hydration Objectives: Determining the extent of lateral deformation u scaffolds made of PVA polymer electrospinning technique. Identify the extent of differences in transverse deformation for different groups of nanofiber scaffolds made of PVA polymer electrospinning technique. Methods: Research scaffolds, we used a measuring device μ-tester, which has two jaws. For the measurement, we chose uniaxial tension test in -tester and record the fluorescence microscope was used with HD camera Olympus 320 for online video recording. Results: The results of this study showed that the ratio of the samples U: L and crosslinking time affects the degree of lateral deformation of the samples scaffolds. Samples scaffolds are compressible, some groups even reached the limits of incompressibility 0.5 Poisson's ratio. Keywords: Poisson, Poisson's ratio, scaffold, nanofiber scaffold, scaffold hydrated, electrospun scaffold, lateral deformation
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