@article{HackethalDungelTeuschl,
  author    = {Hackethal, Johannes and Dungel, Peter and Teuschl, Andreas Herbert},
  title     = {Frequently Used Strategies to Isolate Extracellular Matrix Proteins from Human Placenta and Adipose Tissue},
  series = {Tissue Engineering Part C: Methods},
  volume    = {27},
  journal   = {Tissue Engineering Part C: Methods},
  number    = {12},
  pages     = {649 -- 660},
  abstract  = {The natural extracellular matrix (ECM) provides the optimal environment for cells. Many enzymatic or non-enzymatic based strategies to extract ECM proteins from tissues were published over the past years. However, every single isolation strategy reported so far is associated with specific bottlenecks. In this study, frequently used strategies to isolate ECM from human placenta or adipose tissue using Tris-, serum-, or pepsin-based buffers were compared. The resulting ECM proteins were biochemically characterized by analysis of cellular remnants using Hoechst DNA staining, glycosaminoglycan (GAG) content by dimethylmethylene blue, visualization of protein bands using sodium dodecyl sulfate-polyacrylamide gel electrophoresis analysis combined with amino acid quantification, and assessment of the proangiogenic profile using an angiogenesis array. Tris-NaCl-extracted ECM proteins showed a high heterogenic degree of extracted proteins, bioactive growth factors, and GAGs, but no collagen-I. Active serum-extracted ECM showed significant lower DNA remnants when compared with the Tris-NaCl isolation strategy. Pepsin-extracted ECM was rich in collagen-I and low amounts of remaining bioactive growth factors. This strategy was most effective to reduce DNA amounts when compared with the other isolation strategies. Pepsin-extracted ECM from both tissues easily gelled at 37°C, whereas the other extracted ECM strategies did not gel at 37°C (Tris-NaCl: liquid; serum: sponge). All relevant characteristics (DNA residues, ECM diversity and bioactivity, shape) of the extracted ECM proteins highly depend on its isolation strategy and could still be optimized. Impact statement The natural human extracellular matrix (ECM) is the ideal cell niche. Various strategies were reported to isolate human ECM components from various sources. In this article, we compared frequently used methods and compared their characteristics (DNA remnants, glycosaminoglycan content, sodium dodecyl sulfate-polyacrylamide gel electrophoresis analysis, amino acid quantification, angiogenesis array, and gel formation). We conclude that more research is still necessary to optimize current isolation approaches for in vitro or in vivo applications of human ECM.},
  subject      = {Tissue Engineering},
  language  = {en}
}
@article{KhimichProsolovMishurovaetal.,
  author    = {Khimich, Margarita A. and Prosolov, Konstantin A. and Mishurova, Tatiana and Evsevleev, Sergej and Monforte, Xavier and Teuschl, Andreas H. and Slezak, Paul and Ibragimov, Egor A. and Saprykin, Alexander A. and Kovalevskaya, Zhanna G. and Dmitriev, Andrey I. and Bruno, Giovanni and Sharkeev, Yurii P.},
  title     = {Advances in Laser Additive Manufacturing of Ti-Nb Alloys: From Nanostructured Powders to Bulk Objects},
  series = {Nanomaterials (Basel)},
  volume    = {11},
  journal   = {Nanomaterials (Basel)},
  number    = {5 / 1159},
  abstract  = {The additive manufacturing of low elastic modulus alloys that have a certain level of porosity for biomedical needs is a growing area of research. Here, we show the results of manufacturing of porous and dense samples by a laser powder bed fusion (LPBF) of Ti-Nb alloy, using two distinctive fusion strategies. The nanostructured Ti-Nb alloy powders were produced by mechanical alloying and have a nanostructured state with nanosized grains up to 90 nm. The manufactured porous samples have pronounced open porosity and advanced roughness, contrary to dense samples with a relatively smooth surface profile. The structure of both types of samples after LPBF is formed by uniaxial grains having micro- and nanosized features. The inner structure of the porous samples is comprised of an open interconnected system of pores. The volume fraction of isolated porosity is 2 vol. \% and the total porosity is 20 vol. \%. Cell viability was assessed in vitro for 3 and 7 days using the MG63 cell line. With longer culture periods, cells showed an increased cell density over the entire surface of a porous Ti-Nb sample. Both types of samples are not cytotoxic and could be used for further in vivo studies.},
  subject      = {Tissue Engineering},
  language  = {en}
}
@article{FarokhiAleemardaniSolouketal.,
  author    = {Farokhi, Maryam and Aleemardani, Mina and Solouk, Atefeh and Mirzadeh, Hamid and Teuschl, Andreas Herbert and Redl, Heinz},
  title     = {Crosslinking strategies for silk fibroin hydrogels: promising biomedical materials},
  series = {Biomedical Materials},
  volume    = {16},
  journal   = {Biomedical Materials},
  number    = {2},
  pages     = {022004},
  abstract  = {Due to their strong biomimetic potential, silk fibroin (SF) hydrogels are impressive candidates for tissue engineering, due to their tunable mechanical properties, biocompatibility, low immunotoxicity, controllable biodegradability, and a remarkable capacity for biomaterial modification and the realization of a specific molecular structure. The fundamental chemical and physical structure of SF allows its structure to be altered using various crosslinking strategies. The established crosslinking methods enable the formation of three-dimensional (3D) networks under physiological conditions. There are different chemical and physical crosslinking mechanisms available for the generation of SF hydrogels (SFHs). These methods, either chemical or physical, change the structure of SF and improve its mechanical stability, although each method has its advantages and disadvantages. While chemical crosslinking agents guarantee the mechanical strength of SFH through the generation of covalent bonds, they could cause some toxicity, and their usage is not compatible with a cell-friendly technology. On the other hand, physical crosslinking approaches have been implemented in the absence of chemical solvents by the induction of β-sheet conformation in the SF structure. Unfortunately, it is not easy to control the shape and properties of SFHs when using this method. The current review discusses the different crosslinking mechanisms of SFH in detail, in order to support the development of engineered SFHs for biomedical applications.},
  subject      = {Tissue Engineering},
  language  = {en}
}
@article{BachmannSpitzSchaedletal.,
  author    = {Bachmann, Barbara and Spitz, Sarah and Sch{\"a}dl, Barbara and Teuschl, Andreas and Redl, Heinz and N{\"u}rnberger, Sylvia and Ertl, Peter},
  title     = {Stiffness Matters: Fine-Tuned Hydrogel Elasticity Alters Chondrogenic Redifferentiation},
  series = {Froniers in Bioengineering and Biotechnology},
  volume    = {2020},
  journal   = {Froniers in Bioengineering and Biotechnology},
  number    = {8},
  pages     = {373},
  abstract  = {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.},
  subject      = {Tissue Engineering},
  language  = {en}
}
@article{ZiadlouRotmanTeuschletal.,
  author    = {Ziadlou, Reihane and Rotman, Stijn and Teuschl, Andreas and Salzer, Elias and Barbero, Andrea and Martin, Ivan and Alini, Mauro and Eglin, David and Grad, Sibylle},
  title     = {Optimization of hyaluronic acid-tyramine/silk-fibroin composite hydrogels for cartilage tissue engineering and delivery of anti-inflammatory and anabolic drugs},
  series = {Materials Science and Engineering: C},
  volume    = {120},
  journal   = {Materials Science and Engineering: C},
  number    = {111701},
  abstract  = {Injury of articular cartilage leads to an imbalance in tissue homeostasis, and due to the poor self-healing capacity of cartilage the affected tissue often exhibits osteoarthritic changes. In recent years, injectable and highly tunable composite hydrogels for cartilage tissue engineering and drug delivery have been introduced as a desirable alternative to invasive treatments. In this study, we aimed to formulate injectable hydrogels for drug delivery and cartilage tissue engineering by combining different concentrations of hyaluronic acid-tyramine (HA-Tyr) with regenerated silk-fibroin (SF) solutions. Upon enzymatic crosslinking, the gelation and mechanical properties were characterized over time. To evaluate the effect of the hydrogel compositions and properties on extracellular matrix (ECM) deposition, bovine chondrocytes were embedded in enzymatically crosslinked HA-Tyr/SF composites (in further work abbreviated as HA/SF) or HA-Tyr hydrogels. We demonstrated that all hydrogel formulations were cytocompatible and could promote the expression of cartilage matrix proteins allowing chondrocytes to produce ECM, while the most prominent chondrogenic effects were observed in hydrogels with HA20/SF80 polymeric ratios. Unconfined mechanical testing showed that the compressive modulus for HA20/SF80 chondrocyte-laden constructs was increased almost 10-fold over 28 days of culture in chondrogenic medium which confirmed the superior production of ECM in this hydrogel compared to other hydrogels in this study. Furthermore, in hydrogels loaded with anabolic and anti-inflammatory drugs, HA20/SF80 hydrogel showed the longest and the most sustained release profile over time which is desirable for the long treatment duration typically necessary for osteoarthritic joints. In conclusion, HA20/SF80 hydrogel was successfully established as a suitable injectable biomaterial for cartilage tissue engineering and drug delivery applications.},
  subject      = {Tissue Engineering},
  language  = {en}
}
@misc{TeuschlSchuhWeihsetal.,
  author    = {Teuschl, Andreas and Schuh, Christina and Weihs, Anna and Guillaume, Olivier and Monforte Vila, Xavier and Redl, Heinz and Kaplan, David and R{\"u}nzler, Dominik},
  title     = {Tailoring bioactivity of silk-based biomaterials via delivering and functionalization strategies with fibrinogen/thrombin, plant lectins or laminin},
  subject      = {Biomaterials},
  language  = {en}
}
@article{BerkovitchCohenPeledetal.,
  author    = {Berkovitch, Yulia and Cohen, Talia and Peled, Eli and Schmidhammer, Robert and Hildner, Florian and Teuschl, Andreas and Wolbank, Susanne and Yelin, Dvir and Redl, Heinz and Seliktar, Dror},
  title     = {Hydrogel composition and laser micropatterning to regulate sciatic nerve regeneration.},
  series = {Journal of Tissue Engineering and Regenerative Medicine},
  journal   = {Journal of Tissue Engineering and Regenerative Medicine},
  pages     = {1049 -- 1061},
  abstract  = {Treatment of peripheral nerve injuries has evolved over the past several decades to include the use of sophisticated new materials endowed with trophic and topographical cues that are essential for in vivo nerve fibre regeneration. In this research, we explored the use of an advanced design strategy for peripheral nerve repair, using biological and semi-synthetic hydrogels that enable controlled environmental stimuli to regenerate neurons and glial cells in a rat sciatic nerve resection model. The provisional nerve growth conduits were composed of either natural fibrin or adducts of synthetic polyethylene glycol and fibrinogen or gelatin. A photo-patterning technique was further applied to these 3D hydrogel biomaterials, in the form of laser-ablated microchannels, to provide contact guidance for unidirectional growth following sciatic nerve injury. We tested the regeneration capacity of subcritical nerve gap injuries in rats treated with photo-patterned materials and compared these with injuries treated with unpatterned hydrogels, either stiff or compliant. Among the factors tested were shear modulus, biological composition, and micropatterning of the materials. The microchannel guidance patterns, combined with appropriately matched degradation and stiffness properties of the material, proved most essential for the uniform tissue propagation during the nerve regeneration process.},
  subject      = {Tissue Engineering},
  language  = {en}
}
@misc{TeuschlWeihsFuchsetal.,
  author    = {Teuschl, Andreas and Weihs, Anna and Fuchs, Christiane and Monforte Vila, Xavier},
  title     = {Silk as a versatile biomaterial for musculoskeletal tissue engineering},
  subject      = {Silk},
  language  = {en}
}
@misc{HromadaTomaschWeihsetal.,
  author    = {Hromada, Carina and Tomasch, Janine and Weihs, Anna and R{\"u}nzler, Dominik and Teuschl, Andreas},
  title     = {Engineering of 3D Tissue Constructs Using our Novel MagneTissue Bioreactor as Alternatives to Animal Models},
  subject      = {Bioreactor},
  language  = {en}
}
@article{SchneiderRohringerKapelleretal.,
  author    = {Schneider, Karl and Rohringer, Sabrina and Kapeller, Barbara and Grasl, Christian and Kiss, Herbert and Heber, Stefan and Walter, Ingrid and Teuschl, Andreas and Podesser, Bruno K. and Bergmeister, Helga},
  title     = {Riboflavin-mediated photooxidation to improve the characteristics of decellularized human arterial small diameter vascular grafts},
  series = {Acta Biomater.},
  volume    = {2020},
  journal   = {Acta Biomater.},
  number    = {116},
  pages     = {246 -- 258},
  abstract  = {Vascular grafts with a diameter of less than 6 mm are made from a variety of materials and techniques to provide alternatives to autologous vascular grafts. Decellularized materials have been proposed as a possible approach to create extracellular matrix (ECM) vascular prostheses as they are naturally derived and inherently support various cell functions. However, these desirable graft characteristics may be limited by alterations of the ECM during the decellularization process leading to decreased biomechanical properties and hemocompatibility. In this study, arteries from the human placenta chorion were decellularized using two distinct detergents (Triton X-100 or SDS), which differently affect ECM ultrastructure. To overcome biomechanical strength loss and collagen fiber exposure after decellularization, riboflavin-mediated UV (RUV) crosslinking was used to uniformly crosslink the collagenous ECM of the grafts. Graft characteristics and biocompatibility with and without RUV crosslinking were studied in vitro and in vivo. RUV-crosslinked ECM grafts showed significantly improved mechanical strength and smoothening of the luminal graft surfaces. Cell seeding using human endothelial cells revealed no cytotoxic effects of the RUV treatment. Short-term aortic implants in rats showed cell migration and differentiation of host cells. Functional graft remodeling was evident in all grafts. Thus, RUV crosslinking is a preferable tool to improve graft characteristics of decellularized matrix conduits.},
  subject      = {Tissue Engineering},
  language  = {en}
}