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Title: Complex cell physiology on chemically and topographically designed implant surfaces

J. Barbara Nebe

University of Rostock, Rostock University Medical Center, Germany

Biography

B. Nebe is an adjunct Professor of Cell Biology and chair of the Department of Cell Biology in the Rostock University Medical Center. Nebe received her Ph.D. in 1995 at the University of Rostock, and the Habilitation and venia legendi in 2005 with the theme “Integrin receptors, cell adhesion, and cell signalling”. She is focused on cell biological issues in interfacial interactions of the biosystem to implant surfaces and regenerative medicine. She was invited speaker, e.g. in Paris (2018, THERMEC), and Shanghai (2015, BIT’s RMSC). She was the co-organiser of international symposia, e.g. “Interface Biology of Implants” in Germany. She has published more than 150 research articles in SCI(E) journals.

Abstract

Implant biomaterials should be bioactive in stimulating the surrounding tissue to accelerate the ingrowth of permanent implants, e.g. the dental implants. The critical factor for the ingrowth of permanent implants into bone tissue is rapid cellular acceptance. Although the surface topography is a decisive factor for cell function and adhesion, it turns out that a specific surface chemistry with positive charge carriers can dominate over the topography. Recently, we have shown that a plasma-chemical modification using allylamine as precursor was able to boost not only cell attachment, spreading and cell migration but also intracellular signaling in vital cells. The calcium ion mobilisation capacity was decisively higher in cells growing on plasma polymerised allylamine (PPAAm). The PPAAm plasma process generated a homogenous nanolayer (~50 nm) with randomly distributed, positively charged amino groups. The membrane surface of human osteoblasts is negatively charged due to their spherical coat composed of the extracellular matrix component hyaluronan. Interestingly, sharp-edged micro topographies can be enwrapped completely by cells if coated with the nanolayer of PPAAm. In addition, cells are able to overcome the restrictions of micro-grooves, i.e. the topographically induced contact guidance. However, coating with collagen type I or immobilisation of the integrin adhesion peptide sequence Arg-Gly-Asp (RGD) could not induce the same effect. This plasma-chemical nanocoating PPAAm can be used for several biomaterials in orthopaedic and dental implantology, e.g. titanium, titanium alloys, calcium phosphate scaffolds, or ceramics using Yttria-stabilised tetragonal zirconia [Staehlke S et al. Cell & Bioscience 2018; Moerke C et al. ACS Applied Material Interfaces 2017; Moerke C et al. Biomaterials 2016; Staehlke S et al. Biomaterials 2015; Finke B et al. Biomaterials 2007].