@article{AlzheimerSvenssonKoenigetal.2020,
  author    = {Alzheimer, Mona and Svensson, Sarah L. and K{\"o}nig, Fabian and Schweinlin, Matthias and Metzger, Marco and Walles, Heike and Sharma, Cynthia M.},
  title     = {A three-dimensional intestinal tissue model reveals factors and small regulatory RNAs important for colonization with Campylobacter jejuni},
  series = {PLoS Pathogens},
  volume    = {16},
  journal   = {PLoS Pathogens},
  number    = {2},
  doi       = {10.1371/journal.ppat.1008304},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-229454},
  year      = {2020},
  abstract  = {The Gram-negative Epsilonproteobacterium Campylobacter jejuni is currently the most prevalent bacterial foodborne pathogen. Like for many other human pathogens, infection studies with C. jejuni mainly employ artificial animal or cell culture models that can be limited in their ability to reflect the in-vivo environment within the human host. Here, we report the development and application of a human three-dimensional (3D) infection model based on tissue engineering to study host-pathogen interactions. Our intestinal 3D tissue model is built on a decellularized extracellular matrix scaffold, which is reseeded with human Caco-2 cells. Dynamic culture conditions enable the formation of a polarized mucosal epithelial barrier reminiscent of the 3D microarchitecture of the human small intestine. Infection with C. jejuni demonstrates that the 3D tissue model can reveal isolate-dependent colonization and barrier disruption phenotypes accompanied by perturbed localization of cell-cell junctions. Pathogenesis-related phenotypes of C. jejuni mutant strains in the 3D model deviated from those obtained with 2D-monolayers, but recapitulated phenotypes previously observed in animal models. Moreover, we demonstrate the involvement of a small regulatory RNA pair, CJnc180/190, during infections and observe different phenotypes of CJnc180/190 mutant strains in 2D vs. 3D infection models. Hereby, the CJnc190 sRNA exerts its pathogenic influence, at least in part, via repression of PtmG, which is involved in flagellin modification. Our results suggest that the Caco-2 cell-based 3D tissue model is a valuable and biologically relevant tool between in-vitro and in-vivo infection models to study virulence of C. jejuni and other gastrointestinal pathogens.},
  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{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{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}
}