Cells are embedded into a complex network of protein nanofibers, growth factors and polysaccharides, which make up the extracellular matrix (ECM). This nanofibrous meshwork plays an important role for different biological functions. Such as cell adhesion and proliferation. For this reason, nanostructured biomaterials and their interaction with cells have become a rapidly expanding research field in regenerative medicine.
This study focuses on the interaction of cells with nanofibrous protein scaffolds. Nanofibers were prepared by extruding different ECM proteins in physiological buffers through nanoporous alumina membranes. It was previously shown that the diameter of extruded nanofibers and the mechanical strain could be tailored by adjusting the protein concentration and the nanopore diameter.  Different hierarchical fiber assemblies of either meshes or fibre bundles were obtained with this technique. In the present study we used glass slides, which were partly covered with nanofibrous meshes of extruded collagen, as cell culture substrates. 3T3 fibroblasts were cultivated on the nanofibrous scaffolds to analyse the biofunctionality on a cellular level. Using light microscopy we observed good overall viability of the fibroblasts. Further on, the cells were fixated and their morphology was analysed with scanning electron microscopy. We observed that fibroblasts were growing towards areas on the glass substrates, which were covered with protein nanofibers, thus indicating a positive cellular response.
In the future we will study the cellular interaction with extruded nanofibers from other ECM protein and protein composites and will use our results to develop a new synthetic ECM system for regenerative medicine.
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