CELL-/TISSUE MATERIAL INTERACTIONS
Our group aims to understand the mechanisms of how human cells and tissues interact with materials/material surfaces and, in close collaboration with clinics and industry, to use this knowledge to develop novel materials for unmet clinical needs.
We develop tissue-specific advanced in vitro models that more closely mimic the in vivo situation to investigate the interactions of cells and tissues with materials. We study the early events of blood-material interaction and its influence on human cell response governing integration or non-integration of materials into host tissue as well as cellular processes involved in wound healing, mainly focusing on bone, skin and soft tissue.
Scrutinizing cellular signaling pathways, we explore how the tissue response can be steered with surface functionalization or controlled release of bioactive molecules from materials. Ultimately, we evaluate the predictive power of our models via correlation with in vivo results and clinical data in collaboration with our academic, industrial and clinical partners. For this, we use state of the art techniques including gene- and protein expression analysis as well as microscopy techniques.
Materials to improve wound healing
When damage to the body occurs, healing processes often lead to fibrosis or tissue scarring, where normal tissue is replaced by permanent scar/fibrotic tissue with impaired functionality.
Our goal is to understand the occurrence of and mechanisms involved in impaired wound healing and tissue scarring for the development of novel, material-based treatment strategies. We explore and develop new materials and fabrication concepts to create tailor-made solutions for different wound pathologies. Furthermore, we develop new advanced in vitro 3D co-culture models and use analytical tools including omics-technology, ELISA, SEM or 2-photon microscopy.
Selected research topics:
- Controlling pH by electronic ion pumps to fight fibrosis
- Near-infrared light-sensitive polyvinyl alcohol hydrogel photoresist for spatiotemporal control of cell-instructive 3D microenvironments
- Complex 3D skin models based on a light-sensitive polyvinyl alcohol hydrogel (Skintegrity)
- 3D scaffold based on biodegradable P4HB for the treatment of chronic skin wounds and scar tissue formation (ScarAvoid)
Steering integration and non-integration of materials
Implantable biomaterials are designed to function either in a transient or permanent manner. Depending on the clinical indication, integration of an implant material into the host tissue is desired or needs to be avoided. Generally, fast and specific protein adsorption and enhanced cell migration towards the implant is beneficial in the former situation, whereas non-fouling is favored in the latter one. In both cases however, implant surface properties including roughness, surface chemistry or wettability influence the tissue response to the material. Addition of drug-release functionality to a material can be used to further enhance such a response or to add novel properties such as an antibacterial effect to the material.
Our aim is to understand how such material properties influence different stages of the tissue response to implants, ranging from blood-material interaction to immune cell recruitment to cell differentiation processes, and to develop novel materials and material surfaces to either achieve or to avoid tissue integration. For this, we develop in vitro 3D models that mimic the target tissue and that allow to recreate the situation during implantation of a material in vitro.
- Rationally designed ultra-short pulsed laser patterning of zirconia-based ceramics tailored for the bone-implant interface
- Surface modification of ultrafine‐grained titanium: Influence on mechanical properties, cytocompatibility, and osseointegration potential
- In Vitro Cytocompatibility Assessment of Ti-Modified, Silicon-oxycarbide-Based, Polymer-Derived, Ceramic-Implantable Electrodes under Pacing Conditions
- Enhanced endothelialization of electrospun 3D scaffold interlayers on hyperelastic membranes in pulsatile ventricular assist devices by surface functionalization or hybrid scaffold design (Zurich Heart)
Controlling the immune response towards materials
The immune response is a key element of wound healing and when the body interacts with implanted materials. Encompassing a complex and coordinated series of events, any disturbance can lead to a variety of pathologies or the development of fibrotic tissue in response to implantation of materials.
Our aim is thus to better understand how we can control the immune cell response (e.g. the switch during macrophage polarization into a pro- or anti-inflammatory phenotype) in wound healing but also in contact with engineered materials, and develop novel biomaterials with local immunomodulation capabilities (e.g. 3D scaffolds with controlled drug release).
- In vitro skin culture media influence the viability and inflammatory response of primary macrophages
- Tissue inhibitor of metalloproteinase (TIMP) peptidomimetic as an adjunctive therapy for infectious keratitis
- Lumican is upregulated in osteoarthritis and contributes to TLR4-induced pro-inflammatory activation of cartilage degradation and macrophage polarization
- Silk based scaffolds with immunomodulatory capacity: anti-inflammatory effects of nicotinic acid
Within our different research projects, we collaborate with excellent partners from academia (e.g. Prof. Marcy Zenobi-Wong (ETH Zurich), Prof. Viola Vogel (ETH Zurich), Prof. Jörg Löffler (ETH Zurich), Prof. Jürgen Brugger (EPFL), Prof. Brigitte von Rechenberg (University Zurich), Prof. Simon Pot (University Zurich), Prof. Rainer Riedl (ZHAW Wädenswil), Prof. Heike Walles (University of Magdeburg), Prof. Sally McArthur (Swinburne University), from clinics (e.g. Dr. Karl Grob, (Cantonal Hospital St.Gallen), Dr. Peter Wahl (Cantonal Hospital Winterthur), Dr. Elisabeth Roider (University Hospital Basel), and from industry (e.g. Institut Straumann AG, Lumendo AG, Meddrop AG).
We kindly thank for the financial support by Gebert Rüf Stiftung, Helmut Horten Foundation, Novartis FreeNovation, Novartis Foundation for Medical-Biological Research, SFA Additive Manufacturing, OrthoTrauma Foundation, International Team for Implantology, SNF and Innosuisse.
Dr. med et Dr. med. dent. Matthias G. Wiesli
Dr. Arie Bruinink, Scientist
Dr. Géraldine Guex, Scientist
Dr. Vera Malheiro, PostDoc/Scientist
Dr. Samantha Chan, PostDoc/Scientist
Dr. Xiao-Hua Qin, PostDoc/Scientist
Dr. Eike Müller, PostDoc/Scientist
Dr. Berna Neidhart, PostDoc/Scientist
Rebecca Huber, PhD candidate
Gökce Yazgan, PhD candidate
Lukas Weidenbacher, PhD candidate
Chiara Griffoni, PhD candidate
Anne-Sophie Mertgen, PhD candidate
Amin Zakeri Ziavashani, guest PhD candidate
Marielle Hintereder, Master student
Andrej Eigenmann, Bachelor student
Tanja Schwalm, pre-study internship
Leonie Bannwarth, pre-study internship