@article{SlezakSlezakHartingeretal., author = {Slezak, Paul and Slezak, Cyrill and Hartinger, Joachim and Teuschl, Andreas and N{\"u}rnberger, Sylvia and Redl, Heinz and Mittermayr, Rainer}, title = {A Low Cost Implantation Model in the Rat That Allows a Spatial Assessment of Angiogenesis.}, series = {Frontiers in Bioengineering and Biotechnology}, journal = {Frontiers in Bioengineering and Biotechnology}, abstract = {There is continual demand for animal models that allow a quantitative assessment of angiogenic properties of biomaterials, therapies, and pharmaceuticals. In its simplest form, this is done by subcutaneous material implantation and subsequent vessel counting which usually omits spatial data. We have refined an implantation model and paired it with a computational analytic routine which outputs not only vessel count but also vessel density, distribution, and vessel penetration depth, that relies on a centric vessel as a reference point. We have successfully validated our model by characterizing the angiogenic potential of a fibrin matrix in conjunction with recombinant human vascular endothelial growth factor (rhVEGF165). The inferior epigastric vascular pedicles of rats were sheathed with silicone tubes, which were subsequently filled with 0.2 ml of fibrin and different doses of rhVEGF165, centrically embedding the vessels. Over 4 weeks, tissue samples were harvested and subsequently immunohistologically stained and computationally analyzed. The model was able to detect variations over the angiogenic potentials of growth factor spiked fibrin matrices. Adding 20 ng of rhVEGF165 resulted in a significant increase in vasculature while 200 ng of rhVEGF165 did not improve vascular growth. Vascularized tissue volume increased during the first week and vascular density increased during the second week. Total vessel count increased significantly and exhibited a peak after 2 weeks which was followed by a resorption of vasculature by week 4. In summary, a simple implantation model to study in vivo vascularization with only a minimal workload attached was enhanced to include morphologic data of the emerging vascular tree.}, subject = {Tissue Engineering}, language = {en} } @misc{TeuschlHeimelMonforteVilaetal., author = {Teuschl, Andreas and Heimel, Patrick and Monforte Vila, Xavier and N{\"u}rnberger, Sylvia and Tangl, Stefan and van Griensven, Martijn and Redl, Heinz and Nau, Thomas}, title = {Anterior cruciate ligament regeneration using the silk-based RegACL scaffold}, subject = {Tissue Engineering}, language = {en} } @incollection{HackethalSchuhHoferetal., author = {Hackethal, Johannes and Schuh, Christina and Hofer, Alexandra and Meixner, Barbara and Hennerbichler, Simone and Redl, Heinz and Teuschl, Andreas}, title = {Human Placenta Laminin-111 as a Multifunctional Protein for Tissue Engineering and Regenerative Medicine}, series = {Advances in Experimental Medicine and Biology}, booktitle = {Advances in Experimental Medicine and Biology}, publisher = {Springer}, publisher = {Fachhochschule Technikum Wien}, subject = {Biomaterial}, language = {en} } @article{SchneiderEnayatiGrasletal., author = {Schneider, Karl Heinrich and Enayati, Marjan and Grasl, Christian and Walter, Ingrid and Budinsky, Lubos and Zebic, Gabriel and Kaun, Christoph and Wagner, Anja and Kratochwill, Klaus and Redl, Heinz and Teuschl, Andreas and Podesser, Bruno K. and Bergmeister, Helga}, title = {Acellular vascular matrix grafts from human placenta chorion: Impact of ECM preservation on graft characteristics, protein composition and in vivo performance.}, series = {Biomaterials}, journal = {Biomaterials}, pages = {14 -- 26}, abstract = {Small diameter vascular grafts from human placenta, decellularized with either Triton X-100 (Triton) or SDS and crosslinked with heparin were constructed and characterized. Graft biochemical properties, residual DNA, and protein composition were evaluated to compare the effect of the two detergents on graft matrix composition and structural alterations. Biocompatibility was tested in vitro by culturing the grafts with primary human macrophages and in vivo by subcutaneous implantation of graft conduits (n = 7 per group) into the flanks of nude rats. Subsequently, graft performance was evaluated using an aortic implantation model in Sprague Dawley rats (one month, n = 14). In situ graft imaging was performed using MRI angiography. Retrieved specimens were analyzed by electromyography, scanning electron microscopy, histology and immunohistochemistry to evaluate cell migration and the degree of functional tissue remodeling. Both decellularization methods resulted in grafts of excellent biocompatibility in vitro and in vivo, with low immunogenic potential. Proteomic data revealed removal of cytoplasmic proteins with relative enrichment of ECM proteins in decelluarized specimens of both groups. Noteworthy, LC-Mass Spectrometry analysis revealed that 16 proteins were exclusively preserved in Triton decellularized specimens in comparison to SDS-treated specimens. Aortic grafts showed high patency rates, no signs of thrombus formation, aneurysms or rupture. Conduits of both groups revealed tissue-specific cell migration indicative of functional remodeling. This study strongly suggests that decellularized allogenic grafts from the human placenta have the potential to be used as vascular replacement materials. Both detergents produced grafts with low residual immunogenicity and appropriate mechanical properties. Observed differences in graft characteristics due to preservation method had no impact on successful in vivo performance in the rodent model.}, subject = {Biomaterial}, language = {en} }