title: Induction of osteogenic differentiation by nanostructured alumina surfaces.
abstract: Permanent orthopedic implants are becoming increasingly important due to the demographic development. Their optimal osseointegration is key in obtaining good secondary stability. For anchorage dependent cells, topographic features of a surface play an essential role for cell adhesion, proliferation, differentiation and biomineralization. We studied the topographical effect of nanostructured alumina surfaces prepared by chemical vapor deposition on osteogenic differentiation and growth of human osteoblasts. Chemical vapor deposition of the single source precursor (tBuOAIH2)2 led to synthesis of one dimensional alumina nanostructures of high purity with a controlled stoichiometry. We fabricated different topographic features by altering the distribution density of deposited one dimensional nanostructures. Although the topography differed, all surfaces exhibited identical surface chemistry, which is the key requirement for systematically studying the effect of the topography on cells. Forty-eight hours after seeding, cell density and cell area were not affected by the nanotopography, whereas metabolic activity was reduced and formation of actin-fibres and focal adhesions was impaired compared to the uncoated control. Induction of osteogenic differentiation was demonstrated via up-regulation of alkaline phosphatase, bone sialoprotein, osteopontin and Runx2 at the mRNA level, demonstrating the potential of nanostructured surfaces to improve the osseointegration of permanent implants.
authors.forename: Wolfgang
authors.initials: W
authors.lastname: Metzger
authors.forename: Benedikt
authors.initials: B
authors.lastname: Schwab
authors.forename: Marina M
authors.initials: MM
authors.lastname: Miro
authors.forename: Sibylle
authors.initials: S
authors.lastname: Grad
authors.forename: Angharad
authors.initials: A
authors.lastname: Simpson
authors.forename: Michael
authors.initials: M
authors.lastname: Veith
authors.forename: Gunther
authors.initials: G
authors.lastname: Wennemuth
authors.forename: Vladimir
authors.initials: V
authors.lastname: Zaporojtchenko
authors.forename: Sophie
authors.initials: S
authors.lastname: Verrier
authors.forename: Jessica S
authors.initials: JS
authors.lastname: Hayes
authors.forename: Monika
authors.initials: M
authors.lastname: Bubel
authors.forename: Tim
authors.initials: T
authors.lastname: Pohlemann
authors.forename: Martin
authors.initials: M
authors.lastname: Oberringer
authors.forename: Cenk
authors.initials: C
authors.lastname: Aktas
mesh_terms: D000537:Aluminum Oxide / Q000737:chemistry*; D002454:Cell Differentiation / Q000502:physiology; D049109:Cell Proliferation; D002478:Cells, Cultured; D005260:Female; D006801:Humans; D008297:Male; D008422:Materials Testing; D008875:Middle Aged; D008968:Molecular Conformation; D049329:Nanostructures / Q000737:chemistry* / Q000648:ultrastructure*; D010006:Osteoblasts / Q000166:cytology* / Q000502:physiology*; D010012:Osteogenesis / Q000502:physiology*; D010316:Particle Size; D013499:Surface Properties
chemical_list: D000537:Aluminum Oxide