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Castletroy, Ireland

Stiegler P.,Medical University of Graz | Matzi V.,Medical University of Graz | Pierer E.,Medical University of Graz | Hauser O.,Ziel Biopharma Ltd. | And 10 more authors.
Xenotransplantation | Year: 2010

Introduction: Transplanted cells, especially islet cells, are likely to become apoptotic due to local hypoxia leading to graft dysfunction. Isolated pancreatic islet cells depend on the diffusion of oxygen from the surrounding tissue; therefore, access to sufficient oxygen supply is beneficial, particularly when microcapsules are used for immunoisolation in xenotransplantation. The aim of this study was to create a prevascularized site for cell transplantation in rats and test its effectiveness with microencapsulated HEK293 cells. Methods: The combination of implantation of a foam dressing, vacuum-assisted wound closure (foam+VAC) and hyperbaric oxygenation (HBO) was used in 40 Sprague-Dawley rats. Blood flow and vascular endothelial growth factor (VEGF) levels were determined. Sodium cellulose sulphate (SCS)-microencapsulated HEK293 cells were xenotransplanted into the foam dressing in rats pre-treated with HBO, and angiogenesis and apoptosis were assessed. Results: Vessel ingrowth and VEGF levels increased depending on the duration of HBO treatment. The area containing the foam was perfused significantly better in the experimental groups when compared to controls. Only a small amount of apoptosis occurs in SCS-microencapsulated HEK293 cells after xenotransplantation. Conclusion: As ischemia-damaged cells are likely to undergo cell death or loose functionality due to hypoxia, therefore leading to graft dysfunction, the combination foam+VAC and HBO might be a promising method to create a prevascularized site to achieve better results in xenogeneic cell transplantation. © 2010 John Wiley & Sons A/S. Source


Trademark
Ziel Biopharma Ltd. and Austrianova Biotechnology Gmbh | Date: 2006-01-20

Pharmaceutical and veterinary preparations for the diagnosis and treatment of cancer, auto-immune disorders, infectious diseases, inflammatory diseases, neurological and genetic disorders; microcapsules for release of viral vectors, proteins, enzymes, antibodies, nucleic acids or pharmaceutically active compound; cultures of microorganisms or eukaryotic cells or packaging cells or isolated tissues encased in microcapsules.


Sanz-Nogues C.,National University of Ireland | Horan J.,Ziel Biopharma Ltd. | Thompson K.,Center for Microscopy and Imaging AnatomyNational University of Ireland GalwayNewcastle RoadGalway Ireland | Howard L.,National University of Ireland | And 3 more authors.
Journal of Biomedical Materials Research - Part A | Year: 2015

Microcapsules made of sodium cellulose sulphate (SCS) and poly-diallyl-dimethyl-ammonium chloride (pDADMAC) have been employed to encapsulate a wide range of established cell lines for several applications. However, little is known about the encapsulation of primary cells including human mesenchymal stem cells (hMSCs). Human MSCs are of interest in regenerative medicine applications due to pro-angiogenic, anti-inflammatory and immunomodulatory properties, which result from paracrine effects of this cell type. In the present work we have encapsulated primary hMSCs and hMSC-TERT immortalized cells and compared their behavior and in vitro angiogenic potential. We found that, although both cell types were able to secret angiogenic factors such as VEGF, there was a marked reduction of primary hMSC viability compared to hMSC-TERT cells when cultured in these microcapsules. Moreover, this applied to other primary cell cultures such as primary human fibroblasts but not to other cell lines such as human embryonic kidney 293 (HEK293) cells. We found that the microcapsule membrane had a molecular weight cut-off below a critical size, which caused impairment in the diffusion of essential nutrients and had a more detrimental effect on the viability of primary cell cultures compared to cell lines and immortalized cells. © 2015 Wiley Periodicals, Inc. Source


Sanz-Nogues C.,National University of Ireland | Horan J.,Ziel Biopharma Ltd. | Thompson K.,National University of Ireland | Howard L.,National University of Ireland | And 4 more authors.
Journal of Biomedical Materials Research - Part A | Year: 2015

Microcapsules made of sodium cellulose sulphate (SCS) and poly-diallyl-dimethyl-ammonium chloride (pDADMAC) have been employed to encapsulate a wide range of established cell lines for several applications. However, little is known about the encapsulation of primary cells including human mesenchymal stem cells (hMSCs). Human MSCs are of interest in regenerative medicine applications due to pro-angiogenic, anti-inflammatory and immunomodulatory properties, which result from paracrine effects of this cell type. In the present work we have encapsulated primary hMSCs and hMSC-TERT immortalized cells and compared their behavior and in vitro angiogenic potential. We found that, although both cell types were able to secret angiogenic factors such as VEGF, there was a marked reduction of primary hMSC viability compared to hMSC-TERT cells when cultured in these microcapsules. Moreover, this applied to other primary cell cultures such as primary human fibroblasts but not to other cell lines such as human embryonic kidney 293 (HEK293) cells. We found that the microcapsule membrane had a molecular weight cut-off below a critical size, which caused impairment in the diffusion of essential nutrients and had a more detrimental effect on the viability of primary cell cultures compared to cell lines and immortalized cells. © 2015 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 103A: 3676-3688, 2015. © 2015 Wiley Periodicals, Inc. Source

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