Modifying the surface topography of biomaterials is a promising approach to guide macrophages’ fate to ensure good integration of biomaterials in the host and reduce the risk of implant-associated infections (IAI). High-aspect-ratio titanium nanopillars have shown both bactericidal and osteoconductive properties; however, their effect on immunomodulation is limited researched. Understanding these immunomodulatory effects is important, as the immune response plays a key role in regulating bone regeneration and implant success.

This study investigates the behaviour of J774A.1 macrophages on nanopatterned Dry Etched Titanium (DETi) and polished Titanium (pTi) surfaces, with a focus on cell morphology, migration, proliferation, and cytoskeletal organization. Therefore, stimulated pro-inflammatory (M1) macrophages were cultured on the two substrates and on glass for 48 hours. For morphological evaluation of the cells, the samples were imaged by high resolution fluorescence microscopy after fixation and staining for actin, nucleus and vinculin. Migration was assessed on DETi and pTi samples by creating wounds on the seeded surfaces, measuring the wound closure time. Furthermore, live imaging of M1 macrophages on glass was performed to evaluate their migration and proliferation behaviour.