Local chemotherapy using polymer drug delivery systems has the potential to treat some cancers, including intraocular retinoblastoma, which is difficult to treat with systemically delivered drugs. Well-designed carriers can provide the required drug concentration at the target site over a prolonged time, reduce the overall drug dose needed, and suppress severe side effects. Herein, nanofibrous carriers of the anticancer agent topotecan (TPT) with a multilayered structure composed of a TPT-loaded inner layer of poly(vinyl alcohol) (PVA) and outer covering layers of polyurethane (PUR) are proposed. Scanning electron microscopy showed homogeneous incorporation of TPT into the PVA nanofibers. HPLC-FLD proved the good loading efficiency of TPT (≥85%) with a content of the pharmacologically active lactone TPT of more than 97%. In vitro release experiments demonstrated that the PUR cover layers effectively reduced the initial burst release of hydrophilic TPT. In a 3-round experiment with human retinoblastoma cells (Y-79), TPT showed prolonged release from the sandwich-structured nanofibers compared with that from a PVA monolayer, with significantly enhanced cytotoxic effects as a result of an increase in the PUR layer thickness. The presented PUR-PVA/TPT-PUR nanofibers appear to be promising carriers of active TPT lactone that could be useful for local cancer therapy.
- Publikační typ
- časopisecké články MeSH
This article describes the characterization and application of collagenase-based chitosan nanofiber membranes with rat burns. Electrospun chitosan nanofibers were functionalized with clostridial collagenase using carbodiimide chemistry. The immobilized collagenase was characterized by enzyme activity, kinetic constants, and dry storage stability measurements using a Pz-peptide substrate. The apparent kinetic constants KM and Vmax of immobilized collagenase showed a high affinity for the peptide substrate compared to the free enzyme. Drying of chitosan membranes with immobilized collagenase ensured 98 % stability of enzyme activity after rehydration. The effect of collagenase immobilized on chitosan nanofibers on the burn of the rat model was compared with a control treatment with chitosan nanofibers. The healing of the wound with both materials was terminated after 30 days at the same time, although the collagenase wound healed more rapidly during healing. The scar area size after the application of collagenase-containing chitosan nanofiber membranes was 31.6 % smaller than when only chitosan nanofibers were used.
- MeSH
- chitosan terapeutické užití MeSH
- Clostridium histolyticum MeSH
- enzymy imobilizované MeSH
- hojení ran * účinky léků MeSH
- krysa rodu rattus MeSH
- kůže zranění MeSH
- mikrobiální kolagenasa * metabolismus terapeutické užití MeSH
- nanovlákna terapeutické užití MeSH
- pilotní projekty MeSH
- rány a poranění farmakoterapie patologie MeSH
- stabilita enzymů MeSH
- výsledek terapie MeSH
- zvířata MeSH
- Check Tag
- krysa rodu rattus MeSH
- zvířata MeSH
Stable antimicrobial nanofibrous membrane for air filtration based on polyamide 6 (hereafter PA6) modified by 1-dodecyltrimethylammonium bromide (DTAB) has been prepared by electrospinning using one-step technology, i.e. with modifying antimicrobial agent dissolved in spinning solution. Stability of antibacterial membrane function has been tested by air-blowing test to prove the permanency of chemical composition and antibacterial activity. X-ray diffraction, high-resolution scanning electron microscopy (HRSEM) revealed the effect of modifying agent on structure and morphology of PA6 nanofibres. X-ray photoelectron spectroscopy, electrokinetic analysis and antibacterial tests proved the stability of chemical composition and antibacterial activity after air-blowing tests. Special air-blowing device has been constructed for this purpose. The results prove the applicability so prepared membrane for a long-term air-conditioning.
Various types of nanofibers are increasingly used in tissue engineering, mainly for their ability to mimic the architecture of tissue at the nanoscale. We evaluated the adhesion, growth, viability, and differentiation of human osteoblast-like MG 63 cells on polylactide (PLA) nanofibers prepared by needle-less electrospinning and loaded with 5 or 15 wt % of hydroxyapatite (HA) nanoparticles. On day 7 after seeding, the cell number was the highest on samples with 15 wt % of HA. This result was confirmed by the XTT test, especially after dynamic cultivation, when the number of metabolically active cells on these samples was even higher than on control polystyrene. Staining with a live/dead kit showed that the viability of cells on all nanofibrous scaffolds was very high and comparable to that on control polystyrene dishes. An enzyme-linked immunosorbent assay revealed that the concentration of osteocalcin was also higher in cells on samples with 15 wt % of HA. There was no immune activation of cells (measured by production of TNF-alpha), associated with the incorporation of HA. Moreover, the addition of HA suppressed the creep behavior of the scaffolds in their dry state. Thus, nanofibrous PLA scaffolds have potential for bone tissue engineering, particularly those with 15 wt % of HA.
- MeSH
- buněčná adheze MeSH
- buněčná diferenciace * MeSH
- buněčné linie MeSH
- hydroxyapatit chemie MeSH
- kostní náhrady MeSH
- lidé MeSH
- nanovlákna chemie MeSH
- osteoblasty cytologie metabolismus MeSH
- osteokalcin biosyntéza MeSH
- polyestery chemie MeSH
- tkáňové inženýrství metody MeSH
- viabilita buněk MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
Electrospun gelatin and poly-ε-caprolactone (PCL) nanofibers were prepared using needleless technology and their biocompatibility and therapeutic efficacy have been characterized in vitro in cell cultures and in an experimental model of a skin wound. Human dermal fibroblasts, keratinocytes and mesenchymal stem cells seeded on the nanofibers revealed that both nanofibers promoted cell adhesion and proliferation. The effect of nanofibers on wound healing was examined using a full thickness wound model in rats and compared with a standard control treatment with gauze. Significantly faster wound closure was found with gelatin after 5 and 10 days of treatment, but no enhancement with PCL nanofibers was observed. Histological analysis revealed enhanced epithelialisation, increased depth of granulation tissue and increased density of myofibroblasts in the wound area with gelatin nanofibers. The results show that gelatin nanofibers produced by needleless technology accelerate wound healing and may be suitable as a scaffold for cell transfer and skin regeneration.
- MeSH
- biokompatibilní materiály MeSH
- hojení ran MeSH
- lidé MeSH
- nanovlákna MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
Cyclosporine A (CsA), a potent immunosuppressive drug with low water solubility, was dissolved in poly(L-lactic acid) (PLA) solution, and nanofibers were fabricated from this mixture by electrospinning technology. The addition of CsA into the PLA solution and the conditions of the electrospinning process did not influence the structure of the nanofibers nor affect the pharmacological activity of CsA. Study of the CsA release behavior in culture medium showed a release for at least 96 h. After the topical application of CsA-loaded nanofibers on skin allografts in vivo, the release was significantly slower and about 35% of the drug was still retained in the nanofibers on day 8. The addition of CsA-loaded nanofibers into cultures of mouse spleen cells stimulated with Concanavalin A selectively inhibited T cell functions; the activity of stimulated macrophages or the growth of non-T-cell populations was not suppressed in the presence of CsA-loaded nanofibers. The covering of skin allografts with CsA-loaded nanofibers significantly attenuated the local production of the proinflammatory cytokines IL-2, IFN-γ and IL-17. These results suggest that CsA-loaded electrospun nanofibers can serve as effective drug carriers for the local/topical suppression of an inflammatory reaction and simultaneously could be used as scaffolds for cell-based therapy.
- MeSH
- cyklosporin aplikace a dávkování farmakokinetika farmakologie MeSH
- cytokiny imunologie MeSH
- imunosupresiva aplikace a dávkování farmakokinetika farmakologie MeSH
- kultivované buňky MeSH
- kyselina mléčná chemie MeSH
- myši inbrední BALB C MeSH
- myši inbrední C57BL MeSH
- myši MeSH
- nanovlákna chemie ultrastruktura MeSH
- nosiče léků chemie MeSH
- polymery chemie MeSH
- proliferace buněk účinky léků MeSH
- T-lymfocyty účinky léků imunologie MeSH
- transplantace kůže MeSH
- zvířata MeSH
- Check Tag
- myši MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
Stem cell (SC) therapy represents a promising approach to treat a wide variety of injuries, inherited diseases, or acquired SC deficiencies. One of the major problems associated with SC therapy remains the absence of a suitable matrix for SC growth and transfer. We describe here the growth and metabolic characteristics of mouse limbal stem cells (LSCs) and mesenchymal stem cells (MSCs) growing on 3D nanofiber scaffolds fabricated from polyamide 6/12 (PA6/12). The nanofibers were prepared by the original needleless electrospun Nanospider technology, which enables to create nanofibers of defined diameter, porosity, and a basis weight. Copolymer PA6/12 was selected on the basis of the stability of its nanofibers in aqueous solutions, its biocompatibility, and its superior properties as a matrix for the growth of LSCs, MSCs, and corneal epithelial and endothelial cell lines. The morphology, growth properties, and viability of cells grown on PA6/12 nanofibers were comparable with those grown on plastic. LSCs labeled with the fluorescent dye PKH26 and grown on PA6/12 nanofibers were transferred onto the damaged ocular surface, where their seeding and survival were monitored. Cotransfer of LSCs with MSCs, which have immunosuppressive properties, significantly inhibited local inflammatory reactions and supported the healing process. The results thus show that nanofibers prepared from copolymer PA6/12 represent a convenient scaffold for growth of LSCs and MSCs and transfer to treat SC deficiencies and various ocular surface injuries.
- MeSH
- buněčná diferenciace MeSH
- kaprolaktam analogy a deriváty chemie MeSH
- kmenové buňky cytologie MeSH
- kultivované buňky MeSH
- limbus corneae cytologie MeSH
- mezenchymální kmenové buňky cytologie MeSH
- myši MeSH
- nanovlákna MeSH
- polymery chemie MeSH
- poranění oka terapie MeSH
- proliferace buněk MeSH
- rohovkový epitel cytologie MeSH
- tkáňové inženýrství MeSH
- tkáňové podpůrné struktury MeSH
- transplantace kmenových buněk MeSH
- transplantace mezenchymálních kmenových buněk MeSH
- zvířata MeSH
- Check Tag
- myši MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
