Nanotopographical Coatings Induce an Early Phenotype-Specific Response of Primary Material-Resident M1 and M2 Macrophages

Abstract

Implants elicit an immunological response after implantation that results in the worst case in a complete implant rejection. This biomaterial-induced inflammation is modulated by macrophages and can be influenced by nanotopographical surface structures such as titania nanotubes or fractal titanium nitride (TiN) surfaces. However, their specific impact on a distinct macrophage phenotype has not been identified. By using two different levels of nanostructures and smooth samples as controls, the influence of tubular TiO2 and fractal TiN nanostructures on primary human macrophages with M1 or M2-phenotype was investigated. Therefore, nanotopographical coatings were either, directly generated by physical vapor deposition (PVD) or by electrochemical anodization of titanium PVD coatings. The cellular response of macrophages was quantitatively assessed to demonstrate a difference in biocompatibility of nanotubes in respect to human M1 and M2-macrophages. Depending on the tube diameter of the nanotubular surfaces, low cell numbers and impaired cellular activity, was detected for M2-macrophages, whereas the impact of nanotubes on M1-polarized macrophages was negligible. Importantly, we could confirm this phenotypic response on the fractal TiN surfaces. The results indicate that the investigated topographies specifically impact the macrophage M2-subtype that modulates the formation of the fibrotic capsule and the long-term response to an implant.

Manipulating macrophage polarization with nanoparticles to control metastatic behavior in heterotypic breast cancer micro-tissues via exosome signaling

“…Based on these findings, it can be concluded that PdNPs-induced macrophages effectively suppress metastatic activity in tumor micro-tissues. The function of PdNPs on constraining EMT via inhibition of the TGF-β signaling has been previously reported, 43,44 which highly overlaps with our findings.…”

Nano‐Roughness‐Mediated Macrophage Polarization for Desired Host Immune Response

“…While both phenotypes exhibited round shapes on glass, M2 cells display elongated structures on Ti surfaces. [ 41 ] M0 cells are highly spread on flat bulk metallic glass surfaces, whereas M1 and M2 are more spread, with podia on nanopatterned bulk metallic glass surfaces. [ 42 ] A distinct change in macrophages morphology was reported on different diameters of nanotube surfaces.…”

Antibacterial nanopatterned coatings for dental implants

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