TY - JOUR A1 - Schmid, Rafael A1 - Schmidt, Sonja K. A1 - Hazur, Jonas A1 - Detsch, Rainer A1 - Maurer, Evelyn A1 - Boccaccini, Aldo R. A1 - Hauptstein, Julia A1 - Teßmar, Jörg A1 - Blunk, Torsten A1 - Schrüfer, Stefan A1 - Schubert, Dirk W. A1 - Horch, Raymund E. A1 - Bosserhoff, Anja K. A1 - Arkudas, Andreas A1 - Kengelbach-Weigand, Annika T1 - Comparison of hydrogels for the development of well-defined 3D cancer models of breast cancer and melanoma JF - Cancers N2 - Bioprinting offers the opportunity to fabricate precise 3D tumor models to study tumor pathophysiology and progression. However, the choice of the bioink used is important. In this study, cell behavior was studied in three mechanically and biologically different hydrogels (alginate, alginate dialdehyde crosslinked with gelatin (ADA–GEL), and thiol-modified hyaluronan (HA-SH crosslinked with PEGDA)) with cells from breast cancer (MDA-MB-231 and MCF-7) and melanoma (Mel Im and MV3), by analyzing survival, growth, and the amount of metabolically active, living cells via WST-8 labeling. Material characteristics were analyzed by dynamic mechanical analysis. Cell lines revealed significantly increased cell numbers in low-percentage alginate and HA-SH from day 1 to 14, while only Mel Im also revealed an increase in ADA–GEL. MCF-7 showed a preference for 1% alginate. Melanoma cells tended to proliferate better in ADA–GEL and HA-SH than mammary carcinoma cells. In 1% alginate, breast cancer cells showed equally good proliferation compared to melanoma cell lines. A smaller area was colonized in high-percentage alginate-based hydrogels. Moreover, 3% alginate was the stiffest material, and 2.5% ADA–GEL was the softest material. The other hydrogels were in the same range in between. Therefore, cellular responses were not only stiffness-dependent. With 1% alginate and HA-SH, we identified matrices that enable proliferation of all tested tumor cell lines while maintaining expected tumor heterogeneity. By adapting hydrogels, differences could be accentuated. This opens up the possibility of understanding and analyzing tumor heterogeneity by biofabrication. KW - breast cancer KW - melanoma KW - biofabrication KW - hydrogel KW - tumor heterogeneity Y1 - 2020 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-211195 SN - 2072-6694 VL - 12 IS - 8 ER - TY - JOUR A1 - Schmidt, Stefanie A1 - Abinzano, Florencia A1 - Mensinga, Anneloes A1 - Teßmar, Jörg A1 - Groll, Jürgen A1 - Malda, Jos A1 - Levato, Riccardo A1 - Blunk, Torsten T1 - Differential production of cartilage ECM in 3D agarose constructs by equine articular cartilage progenitor cells and mesenchymal stromal cells JF - International Journal of Molecular Sciences N2 - Identification of articular cartilage progenitor cells (ACPCs) has opened up new opportunities for cartilage repair. These cells may be used as alternatives for or in combination with mesenchymal stromal cells (MSCs) in cartilage engineering. However, their potential needs to be further investigated, since only a few studies have compared ACPCs and MSCs when cultured in hydrogels. Therefore, in this study, we compared chondrogenic differentiation of equine ACPCs and MSCs in agarose constructs as monocultures and as zonally layered co-cultures under both normoxic and hypoxic conditions. ACPCs and MSCs exhibited distinctly differential production of the cartilaginous extracellular matrix (ECM). For ACPC constructs, markedly higher glycosaminoglycan (GAG) contents were determined by histological and quantitative biochemical evaluation, both in normoxia and hypoxia. Differential GAG production was also reflected in layered co-culture constructs. For both cell types, similar staining for type II collagen was detected. However, distinctly weaker staining for undesired type I collagen was observed in the ACPC constructs. For ACPCs, only very low alkaline phosphatase (ALP) activity, a marker of terminal differentiation, was determined, in stark contrast to what was found for MSCs. This study underscores the potential of ACPCs as a promising cell source for cartilage engineering. KW - ACPC KW - chondroprogenitors KW - tissue engineering KW - MSC KW - agarose KW - hypoxia KW - ECM KW - co-culture KW - zonal KW - cartilage Y1 - 2020 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-236180 SN - 1422-0067 VL - 21 IS - 19 ER - TY - JOUR A1 - Hazur, Jonas A1 - Detsch, Rainer A1 - Karakaya, Emine A1 - Kaschta, Joachim A1 - Teßmar, Jörg A1 - Schneidereit, Dominik A1 - Friedrich, Oliver A1 - Schubert, Dirk W A1 - Boccaccini, Aldo R T1 - Improving alginate printability for biofabrication: establishment of a universal and homogeneous pre-crosslinking technique JF - Biofabrication N2 - Many different biofabrication approaches as well as a variety of bioinks have been developed by researchers working in the field of tissue engineering. A main challenge for bioinks often remains the difficulty to achieve shape fidelity after printing. In order to overcome this issue, a homogeneous pre-crosslinking technique, which is universally applicable to all alginate-based materials, was developed. In this study, the Young’s Modulus after post-crosslinking of selected hydrogels, as well as the chemical characterization of alginate in terms of M/G ratio and molecular weight, were determined. With our technique it was possible to markedly enhance the printability of a 2% (w/v) alginate solution, without using a higher polymer content, fillers or support structures. 3D porous scaffolds with a height of around 5 mm were printed. Furthermore, the rheological behavior of different pre-crosslinking degrees was studied. Shear forces on cells as well as the flow profile of the bioink inside the printing nozzle during the process were estimated. A high cell viability of printed NIH/3T3 cells embedded in the novel bioink of more than 85% over a time period of two weeks could be observed. KW - alginate KW - bioprinting KW - rheology KW - bioink KW - pre-crosslinking KW - printability KW - shape fidelity Y1 - 2020 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-254030 VL - 12 IS - 4 ER -