TY - JOUR A1 - Bachmann, Barbara A1 - Spitz, Sarah A1 - Schädl, Barbara A1 - Teuschl, Andreas A1 - Redl, Heinz A1 - Nürnberger, Sylvia A1 - Ertl, Peter T1 - Stiffness Matters: Fine-Tuned Hydrogel Elasticity Alters Chondrogenic Redifferentiation JF - Froniers in Bioengineering and Biotechnology N2 - Biomechanical cues such as shear stress, stretching, compression, and matrix elasticity are vital in the establishment of next generation physiological in vitro tissue models. Matrix elasticity, for instance, is known to guide stem cell differentiation, influence healing processes and modulate extracellular matrix (ECM) deposition needed for tissue development and maintenance. To better understand the biomechanical effect of matrix elasticity on the formation of articular cartilage analogs in vitro, this study aims at assessing the redifferentiation capacity of primary human chondrocytes in three different hydrogel matrices of predefined matrix elasticities. The hydrogel elasticities were chosen to represent a broad spectrum of tissue stiffness ranging from very soft tissues with a Young's modulus of 1 kPa up to elasticities of 30 kPa, representative of the perichondral-space. In addition, the interplay of matrix elasticity and transforming growth factor beta-3 (TGF-β3) on the redifferentiation of primary human articular chondrocytes was studied by analyzing both qualitative (viability, morphology, histology) and quantitative (RT-qPCR, sGAG, DNA) parameters, crucial to the chondrotypic phenotype. Results show that fibrin hydrogels of 30 kPa Young's modulus best guide chondrocyte redifferentiation resulting in a native-like morphology as well as induces the synthesis of physiologic ECM constituents such as glycosaminoglycans (sGAG) and collagen type II. This comprehensive study sheds light onto the mechanobiological impact of matrix elasticity on formation and maintenance of articular cartilage and thus represents a major step toward meeting the need for advanced in vitro tissue models to study both re- and degeneration of articular cartilage. KW - Tissue Engineering KW - Chondrogenic Redifferentiation KW - Biomaterials Y1 - 2021 VL - 2020 IS - 8 SP - 373 ER - TY - JOUR A1 - Slezak, Paul A1 - Slezak, Cyrill A1 - Hartinger, Joachim A1 - Teuschl, Andreas A1 - Nürnberger, Sylvia A1 - Redl, Heinz A1 - Mittermayr, Rainer T1 - A Low Cost Implantation Model in the Rat That Allows a Spatial Assessment of Angiogenesis. JF - Frontiers in Bioengineering and Biotechnology N2 - 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. KW - Tissue Engineering KW - Bioreactor KW - Biomaterial Y1 - ER - TY - GEN A1 - Teuschl, Andreas A1 - Heimel, Patrick A1 - Monforte Vila, Xavier A1 - Nürnberger, Sylvia A1 - Tangl, Stefan A1 - van Griensven, Martijn A1 - Redl, Heinz A1 - Nau, Thomas T1 - Anterior cruciate ligament regeneration using the silk-based RegACL scaffold KW - Tissue Engineering KW - Silk KW - Biomaterial KW - Anterior Cruciate Ligament Y1 - ER - TY - JOUR A1 - Schneider, Cornelia A1 - Lehmann, Johannes A1 - van Osch, Gerjo A1 - Hildner, Florian A1 - Teuschl, Andreas A1 - Monforte Vila, Xavier A1 - Miosga, David A1 - Heimel, Patrick A1 - Priglinger, Eleni A1 - Redl, Heinz A1 - Wolbank, Susanne A1 - Nürnberger, Sylvia T1 - Systematic Comparison of Protocols for the Preparation of Human Articular Cartilage for Use as Scaffold Material in Cartilage Tissue Engineering JF - Tissue Eng Part C Methods KW - Cartilage KW - Scaffold Material Y1 - 2018 VL - 22 IS - 12 ER - TY - GEN A1 - Teuschl, Andreas A1 - Heimel, Patrick A1 - Nürnberger, Sylvia A1 - Redl, Heinz A1 - Nau, Thomas T1 - ACL Regeneration using a novel silk fiber based scaffold - Histological Results of a Large Animal Study KW - Tissue Regeneration KW - Silk KW - Scaffold Y1 - 2018 ER - TY - JOUR A1 - Teuschl, Andreas A1 - Heimel, Patrick A1 - Nürnberger, Sylvia A1 - van Griensven, Martijn A1 - Redl, Heinz A1 - Nau, Thomas T1 - A Novel Silk Fiber-Based Scaffold for Regeneration of the Anterior Cruciate Ligament: Histological Results From a Study in Sheep. JF - The American Journal of Sports Medicine KW - Ligament KW - Regeneration Y1 - 2018 ER - TY - GEN A1 - Teuschl, Andreas A1 - Fuchs, Christiane A1 - Feichtinger, Georg A1 - Heher, Philipp A1 - Heimel, Patrick A1 - Schuh, Christina A1 - Nürnberger, Sylvia A1 - Nau, Thomas A1 - Rünzler, Dominik A1 - Redl, Heinz T1 - Fibrin or Fibroin - Not only the "o" Makes the Difference KW - Fibrin KW - Fibroin Y1 - 2018 ER - TY - GEN A1 - Teuschl, Andreas A1 - Nürnberger, Sylvia A1 - Heimel, Patrick A1 - Redl, Heinz A1 - Nau, Thomas T1 - Regeneration of the Anterior Cruciate Ligament Using a Silk-Fiber Based Scaffold - Histological Results KW - Tissue Regeneration KW - Ligaments KW - Scaffold Y1 - 2018 ER - TY - JOUR A1 - Banerjee, Asmita A1 - Nürnberger, Sylvia A1 - Hennerbichler, Simone A1 - Riedl, Stefan A1 - Schuh, Christina A1 - Hacobian, Ara A1 - Teuschl, Andreas A1 - Eibl, Jürgen A1 - Redl, Heinz T1 - In toto differentiation of human amniotic membrane towards the Schwann cell lineage JF - 227-239 KW - Membrane KW - In toto differentiation Y1 - 2018 VL - 15 IS - 2 ER - TY - JOUR A1 - Teuschl, Andreas A1 - Nürnberger, Sylvia A1 - Redl, Heinz A1 - Nau, Thomas T1 - Articular cartilage tissue regeneration: current research strategies and outlook for the future JF - European Surgery KW - Tissue Regeneration KW - Cartilage Tissue Y1 - 2018 VL - 45 IS - 3 SP - 142 EP - 153 ER -