@article{SchmitzJannaschWeigeletal.2020, author = {Schmitz, Tobias and Jannasch, Maren and Weigel, Tobias and Moseke, Claus and Gbureck, Uwe and Groll, J{\"u}rgen and Walles, Heike and Hansmann, Jan}, title = {Nanotopographical Coatings Induce an Early Phenotype-Specific Response of Primary Material-Resident M1 and M2 Macrophages}, series = {Materials}, volume = {13}, journal = {Materials}, number = {5}, issn = {1996-1944}, doi = {10.3390/ma13051142}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-203378}, year = {2020}, abstract = {Implants elicit an immunological response after implantation that results in the worst case in a complete implant rejection. This biomaterial-induced inflammation is modulated by macrophages and can be influenced by nanotopographical surface structures such as titania nanotubes or fractal titanium nitride (TiN) surfaces. However, their specific impact on a distinct macrophage phenotype has not been identified. By using two different levels of nanostructures and smooth samples as controls, the influence of tubular TiO2 and fractal TiN nanostructures on primary human macrophages with M1 or M2-phenotype was investigated. Therefore, nanotopographical coatings were either, directly generated by physical vapor deposition (PVD) or by electrochemical anodization of titanium PVD coatings. The cellular response of macrophages was quantitatively assessed to demonstrate a difference in biocompatibility of nanotubes in respect to human M1 and M2-macrophages. Depending on the tube diameter of the nanotubular surfaces, low cell numbers and impaired cellular activity, was detected for M2-macrophages, whereas the impact of nanotubes on M1-polarized macrophages was negligible. Importantly, we could confirm this phenotypic response on the fractal TiN surfaces. The results indicate that the investigated topographies specifically impact the macrophage M2-subtype that modulates the formation of the fibrotic capsule and the long-term response to an implant.}, language = {en} } @article{SchwedhelmZdziebloAppeltMenzeletal.2019, author = {Schwedhelm, Ivo and Zdzieblo, Daniela and Appelt-Menzel, Antje and Berger, Constantin and Schmitz, Tobias and Schuldt, Bernhard and Franke, Andre and M{\"u}ller, Franz-Josef and Pless, Ole and Schwarz, Thomas and Wiedemann, Philipp and Walles, Heike and Hansmann, Jan}, title = {Automated real-time monitoring of human pluripotent stem cell aggregation in stirred tank reactors}, series = {Scientific Reports}, volume = {9}, journal = {Scientific Reports}, doi = {10.1038/s41598-019-48814-w}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-202649}, pages = {12297}, year = {2019}, abstract = {The culture of human induced pluripotent stem cells (hiPSCs) at large scale becomes feasible with the aid of scalable suspension setups in continuously stirred tank reactors (CSTRs). Innovative monitoring options and emerging automated process control strategies allow for the necessary highly defined culture conditions. Next to standard process characteristics such as oxygen consumption, pH, and metabolite turnover, a reproducible and steady formation of hiPSC aggregates is vital for process scalability. In this regard, we developed a hiPSC-specific suspension culture unit consisting of a fully monitored CSTR system integrated into a custom-designed and fully automated incubator. As a step towards cost-effective hiPSC suspension culture and to pave the way for flexibility at a large scale, we constructed and utilized tailored miniature CSTRs that are largely made from three-dimensional (3D) printed polylactic acid (PLA) filament, which is a low-cost material used in fused deposition modelling. Further, the monitoring tool for hiPSC suspension cultures utilizes in situ microscopic imaging to visualize hiPSC aggregation in real-time to a statistically significant degree while omitting the need for time-intensive sampling. Suitability of our culture unit, especially concerning the developed hiPSC-specific CSTR system, was proven by demonstrating pluripotency of CSTR-cultured hiPSCs at RNA (including PluriTest) and protein level.}, language = {en} } @article{JannaschWeigelEngelhardtetal.2017, author = {Jannasch, Maren and Weigel, Tobias and Engelhardt, Lisa and Wiezoreck, Judith and Gaetzner, Sabine and Walles, Heike and Schmitz, Tobias and Hansmann, Jan}, title = {\({In}\) \({vitro}\) chemotaxis and tissue remodeling assays quantitatively characterize foreign body reaction}, series = {ALTEX - Alternatives to Animal Experimentation}, volume = {34}, journal = {ALTEX - Alternatives to Animal Experimentation}, number = {2}, doi = {10.14573/altex.1610071}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-172080}, pages = {253-266}, year = {2017}, abstract = {Surgical implantation of a biomaterial triggers foreign-body-induced fibrous encapsulation. Two major mechanisms of this complex physiological process are (I) chemotaxis of fibroblasts from surrounding tissue to the implant region, followed by (II) tissue remodeling. As an alternative to animal studies, we here propose a process-aligned \({in}\) \({vitro}\) test platform to investigate the material dependency of fibroblast chemotaxis and tissue remodeling mediated by material-resident macrophages. Embedded in a biomimetic three-dimensional collagen hydrogel, chemotaxis of fibroblasts in the direction of macrophage-material-conditioned cell culture supernatant was analyzed by live cell imaging. A combination of statistical analysis with a complementary parameterized random walk model allowed quantitative and qualitative characterization of the cellular walk process. We thereby identified an increasing macrophage-mediated chemotactic potential ranking of biomaterials from glass over polytetrafluorethylene to titanium. To address long-term effects of biomaterial-resident macrophages on fibroblasts in a three-dimensional microenvironment, we further studied tissue remodeling by applying macrophage-material-conditioned medium on fibrous \({in}\) \({vitro}\) tissue models. A high correlation of the \({in}\) \({vitro}\) tissue model to state of the art \({in}\) \({vivo}\) study data was found. Titanium exhibited a significantly lower tissue remodeling capacity compared to polytetrafluorethylene. With this approach, we identified a material dependency of both chemotaxis and tissue remodeling processes, strengthening knowledge on their specific contribution to the foreign body reaction.}, language = {en} } @article{JannaschGaetznerWeigeletal.2017, author = {Jannasch, Maren and Gaetzner, Sabine and Weigel, Tobias and Walles, Heike and Schmitz, Tobias and Hansmann, Jan}, title = {A comparative multi-parametric in vitro model identifies the power of test conditions to predict the fibrotic tendency of a biomaterial}, series = {Scientific Reports}, volume = {7}, journal = {Scientific Reports}, number = {1689}, doi = {10.1038/s41598-017-01584-9}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-170908}, year = {2017}, abstract = {Despite growing effort to advance materials towards a low fibrotic progression, all implants elicit adverse tissue responses. Pre-clinical biomaterial assessment relies on animals testing, which can be complemented by in vitro tests to address the Russell and Burch's 3R aspect of reducing animal burden. However, a poor correlation between in vitro and in vivo biomaterial assessments confirms a need for suitable in vitro biomaterial tests. The aim of the study was to identify a test setting, which is predictive and might be time- and cost-efficient. We demonstrated how sensitive in vitro biomaterial assessment based on human primary macrophages depends on test conditions. Moreover, possible clinical scenarios such as lipopolysaccharide contamination, contact to autologous blood plasma, and presence of IL-4 in an immune niche influence the outcome of a biomaterial ranking. Nevertheless, by using glass, titanium, polytetrafluorethylene, silicone, and polyethylene representing a specific material-induced fibrotic response and by comparison to literature data, we were able to identify a test condition that provides a high correlation to state-of-the-art in vivo studies. Most important, biomaterial ranking obtained under native plasma test conditions showed a high predictive accuracy compared to in vivo assessments, strengthening a biomimetic three-dimensional in vitro test platform.}, language = {en} } @article{BrendtkeWiehlGroeberetal.2016, author = {Brendtke, Rico and Wiehl, Michael and Groeber, Florian and Schwarz, Thomas and Walles, Heike and Hansmann, Jan}, title = {Feasibility Study on a Microwave-Based Sensor for Measuring Hydration Level Using Human Skin Models}, series = {PLoS ONE}, volume = {11}, journal = {PLoS ONE}, number = {4}, doi = {10.1371/journal.pone.0153145}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-179934}, year = {2016}, abstract = {Tissue dehydration results in three major types of exsiccosis—hyper-, hypo-, or isonatraemia. All three types entail alterations of salt concentrations leading to impaired biochemical processes, and can finally cause severe morbidity. The aim of our study was to demonstrate the feasibility of a microwave-based sensor technology for the non-invasive measurement of the hydration status. Electromagnetic waves at high frequencies interact with molecules, especially water. Hence, if a sample contains free water molecules, this can be detected in a reflected microwave signal. To develop the sensor system, human three-dimensional skin equivalents were instituted as a standardized test platform mimicking reproducible exsiccosis scenarios. Therefore, skin equivalents with a specific hydration and density of matrix components were generated and microwave measurements were performed. Hydration-specific spectra allowed deriving the hydration state of the skin models. A further advantage of the skin equivalents was the characterization of the impact of distinct skin components on the measured signals to investigate mechanisms of signal generation. The results demonstrate the feasibility of a non-invasive microwave-based hydration sensor technology. The sensor bears potential to be integrated in a wearable medical device for personal health monitoring.}, language = {en} } @article{GroeberEngelhardtLangeetal.2016, author = {Groeber, Florian and Engelhardt, Lisa and Lange, Julia and Kurdyn, Szymon and Schmid, Freia F. and R{\"u}cker, Christoph and Mielke, Stephan and Walles, Heike and Hansmann, Jan}, title = {A First Vascularized Skin Equivalent as an Alternative to Animal Experimentation}, series = {ALTEX - Alternatives to Animal Experimentation}, volume = {33}, journal = {ALTEX - Alternatives to Animal Experimentation}, number = {4}, doi = {10.14573/altex.1604041}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-164438}, pages = {415-422}, year = {2016}, abstract = {Tissue-engineered skin equivalents mimic key aspects of the human skin, and can thus be employed as wound coverage for large skin defects or as in vitro test systems as an alternative to animal models. However, current skin equivalents lack a functional vasculature limiting clinical and research applications. This study demonstrates the generation of a vascularized skin equivalent with a perfused vascular network by combining a biological vascularized scaffold (BioVaSc) based on a decellularized segment of a porcine jejunum and a tailored bioreactor system. Briefly, the BioVaSc was seeded with human fibroblasts, keratinocytes, and human microvascular endothelial cells. After 14 days at the air-liquid interface, hematoxylin \& eosin and immunohistological staining revealed a specific histological architecture representative of the human dermis and epidermis including a papillary-like architecture at the dermal-epidermal-junction. The formation of the skin barrier was measured non-destructively using impedance spectroscopy. Additionally, endothelial cells lined the walls of the formed vessels that could be perfused with a physiological volume flow. Due to the presence of a complex in-vivo-like vasculature, the here shown skin equivalent has the potential for skin grafting and represents a sophisticated in vitro model for dermatological research.}, language = {en} } @article{NietzerBaurSieberetal.2016, author = {Nietzer, Sarah and Baur, Florentin and Sieber, Stefan and Hansmann, Jan and Schwarz, Thomas and Stoffer, Carolin and H{\"a}fner, Heide and Gasser, Martin and Waaga-Gasser, Ana Maria and Walles, Heike and Dandekar, Gudrun}, title = {Mimicking metastases including tumor stroma: a new technique to generate a three-dimensional colorectal cancer model based on a biological decellularized intestinal scaffold}, series = {Tissue Engineering Part C-Methods}, volume = {22}, journal = {Tissue Engineering Part C-Methods}, number = {7}, doi = {10.1089/ten.tec.2015.0557}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-188202}, pages = {621-635}, year = {2016}, abstract = {Tumor models based on cancer cell lines cultured two-dimensionally (2D) on plastic lack histological complexity and functionality compared to the native microenvironment. Xenogenic mouse tumor models display higher complexity but often do not predict human drug responses accurately due to species-specific differences. We present here a three-dimensional (3D) in vitro colon cancer model based on a biological scaffold derived from decellularized porcine jejunum (small intestine submucosa+mucosa, SISmuc). Two different cell lines were used in monoculture or in coculture with primary fibroblasts. After 14 days of culture, we demonstrated a close contact of human Caco2 colon cancer cells with the preserved basement membrane on an ultrastructural level as well as morphological characteristics of a well-differentiated epithelium. To generate a tissue-engineered tumor model, we chose human SW480 colon cancer cells, a reportedly malignant cell line. Malignant characteristics were confirmed in 2D cell culture: SW480 cells showed higher vimentin and lower E-cadherin expression than Caco2 cells. In contrast to Caco2, SW480 cells displayed cancerous characteristics such as delocalized E-cadherin and nuclear location of beta-catenin in a subset of cells. One central drawback of 2D cultures-especially in consideration of drug testing-is their artificially high proliferation. In our 3D tissue-engineered tumor model, both cell lines showed decreased numbers of proliferating cells, thus correlating more precisely with observations of primary colon cancer in all stages (UICC I-IV). Moreover, vimentin decreased in SW480 colon cancer cells, indicating a mesenchymal to epithelial transition process, attributed to metastasis formation. Only SW480 cells cocultured with fibroblasts induced the formation of tumor-like aggregates surrounded by fibroblasts, whereas in Caco2 cocultures, a separate Caco2 cell layer was formed separated from the fibroblast compartment beneath. To foster tissue generation, a bioreactor was constructed for dynamic culture approaches. This induced a close tissue-like association of cultured tumor cells with fibroblasts reflecting tumor biopsies. Therapy with 5-fluorouracil (5-FU) was effective only in 3D coculture. In conclusion, our 3D tumor model reflects human tissue-related tumor characteristics, including lower tumor cell proliferation. It is now available for drug testing in metastatic context-especially for substances targeting tumor-stroma interactions.}, language = {en} }