Dr. Susanne Semmann (Rostock, DE), Dr. Susanne Stählke (Rostock, DE), Manuela Dubs (Jena, DE), Dr. Dirk Koczan (Rostock, DE), Dr. Hernando S. Salapare III (Mulhouse, FR), Dr. Arnaud Ponche (Mulhouse, FR), Dr. Annika Wartenberg (Jena, DE), Dr. Matthias Schnabelrauch (Jena, DE), Dr. Karine Anselme (Mulhouse, FR), Prof. Dr. J. Barbara Nebe (Rostock, DE)
Abstract text (incl. figure legends and references)
Demographic change in industrialized countries results in an increased incidence of osteoporosis. Most of the implants are not adapted for use in systemically diseased bone and therefore, osseointegration is a challenge. Amine-based coatings improve initial cell attachment, and signaling1,2. The question arose if there is a correlation between amino group density and cell response.
Covalent grafting of polymer-based nano-coatings on titanium (ZfM Chemnitz) with different amino group densities was prepared by INNOVENT e.V., e.g. trimethoxysilylpropyl modified poly(ethyleneimine (TMS-PEI). For protein adsorption, size-exclusion HPLC was used (λ 215 nm). WCA, zeta potential and XPS characterized the surface coatings. Cell areas (PKH-26) of human MG-63 cells (ATCC®) were determined via LSM780 (Carl Zeiss), and differential gene expression via ClariomTM S microarrays (Applied Biosystems).
Interestingly, a correlation exists between amino group density and cell spreading (Fig. 1). TMS-PEI offers the highest amino group density (N/C 32.2%) and positive surface charges, which is preferred by cells2. A premature activation of cell proliferation and differentiation was identified. BSA adsorption is highest on TMS-PEI compared to Ti-Ref. The fact that differentiation on amine-based coatings is enhanced has already been shown, but no microarray data are available now. The effects of TMS-PEI could compensate for the age-related slowing of osteoblast proliferation3 and thus promote osseointegration.
Fig. 1: MG-63s on different polymer coatings with increased amino group density. TMS-PEI pushed significantly the cell spreading after 30 min.
References
Chen S. et al., Colloids Surf B Biointerfaces, 164:58-69, 2018 Gruening M. et al., Front Bioeng Biotechnol, 8:1016, 2020 Rauner M. et al., Age (Dordr), 30(4):273-82, 2008Acknowledgments: Funded by the (i) ANR-DFG NLE2020 (DFG NE560/19-1, SCHN1099/9-1, no. 446225522) and (ii) Agence Nationale de la Recherche (ANR-20-CE92-0032).