title: On the interactions of human bone cells with Ti6Al4V thermally oxidized by means of laser shock processing.
abstract: We investigated a Ti6Al4V alloy modified by means of laser peening in the absence of sacrificial coatings. As a consequence of the temperature rise during laser focusing, melting and ablation generated an undulated surface that exhibits an important increase in the content of titanium oxides and OH- ions. Human mesenchymal stem cells and osteoblasts cultured on the oxidized alloy develop noticeable filopodia and lamellipodia. Their paxillin-stained focal adhesions are smaller than in cells attached to the untreated alloy and exhibit a marked loss of colocalization with the ends of actin stress fibers. An important imbalance of phosphorylation and/or dephosphorylation of the focal adhesion kinase is detected in cells grown on the oxidized alloy. Although these mechanisms of adhesion are deeply altered, the surface treatment does not affect cell attachment or proliferation rates on the alloy. Human mesenchymal stem cells cultured on the treated alloy in media containing osteogenic inducers differentiate towards the osteoblastic phenotype to a higher extent than those on the untreated surface. Also, the specific functions of human osteoblasts cultured on these media are enhanced on the treated alloy. In summary, laser peening tailors the Ti6Al4V surface to yield an oxidized layer with increased roughness that allows the colonization and activities of bone-lineage cells.
authors.affiliation: Hospital Universitario La Paz-IdiPAZ, Paseo de la Castellana 261, 28046 Madrid, Spain. CIBER de Bioingeniería, Biomateriales y Nanomedicina (CIBER-BBN), Spain.
authors.forename: Lara
authors.initials: L
authors.lastname: Crespo
authors.forename: Margarita
authors.initials: M
authors.lastname: Hierro-Oliva
authors.forename: Sandra
authors.initials: S
authors.lastname: Barriuso
authors.forename: Virginia
authors.initials: V
authors.lastname: Vadillo-Rodríguez
authors.forename: M Ángeles
authors.initials: MÁ
authors.lastname: Montealegre
authors.forename: Laura
authors.initials: L
authors.lastname: Saldaña
authors.forename: Enrique
authors.initials: E
authors.lastname: Gomez-Barrena
authors.forename: José Luis
authors.initials: JL
authors.lastname: González-Carrasco
authors.forename: María Luisa
authors.initials: ML
authors.lastname: González-Martín
authors.forename: Nuria
authors.initials: N
authors.lastname: Vilaboa
mesh_terms: D018786:Bone Substitutes / Q000737:chemistry* / Q000528:radiation effects; D002448:Cell Adhesion / Q000502:physiology; D002454:Cell Differentiation / Q000502:physiology; D049109:Cell Proliferation / Q000502:physiology; D002470:Cell Survival / Q000502:physiology; D002478:Cells, Cultured; D006361:Heating / Q000379:methods*; D006801:Humans; D007834:Lasers; D008422:Materials Testing; D010006:Osteoblasts / Q000166:cytology* / Q000502:physiology*; D010084:Oxidation-Reduction / Q000528:radiation effects; D013499:Surface Properties / Q000528:radiation effects; D014025:Titanium / Q000737:chemistry* / Q000528:radiation effects
chemical_list: D018786:Bone Substitutes; C070282:Ti-6Al-7Nb alloy; D014025:Titanium