Polydopamine-based biofunctional substrate coating promotes mesenchymal stem cell migration

Rapid migration of mesenchymal stem cells (MSCs) on device surfaces could support in vivo tissue integration and might facilitate in vitro organoid formation. Here, polydopamine (PDA) is explored as a biofunctional coating to effectively promote MSC motility. It is hypothesized that PDA stimulates fibronectin deposition and in this way enhances integrin-mediated migration capability. The random and directional cell migration was investigated by time-lapse microscopy and gap closure assay respectively, and analysed with softwares as computational tools. A higher amount of deposited fibronectin was observed on PDA substrate, compared to the non-coated substrate. The integrin β1 activation and focal adhesion kinase (FAK) phosphorylation at Y397 were enhanced on PDA substrate, but the F-actin cytoskeleton was not altered, suggesting MSC migration on PDA was regulated by integrin initiated FAK signalling. This study strengthens the biofunctionality of PDA coating for regulating stem cells and offering a way of facilitating tissue integration of devices. Graphic abstract Polydopamine-coated substrate induces increased fibronectin deposition of mesenchymal stem cells, and promotes cell migration via integrin-initiated FAK signaling, compared to non-coated polystyrene-based standard tissue culture surface. In this way, multifunctional PDA coating could support in vivo tissue integration on implant surface and promote in vitro organoid formation.