title: Effect of bioactive extruded PLA/HA composite films on focal adhesion formation of preosteoblastic cells.
abstract: The quality of the initial cell attachment to a biomaterial will influence any further cell function, including spreading, proliferation, differentiation and viability. Cell attachment is influenced by the material's ability to adsorb proteins, which is related to the surface chemistry and topography of the material. In this study, we incorporated hydroxyapatite (HA) particles into a poly(lactic acid) (PLA) composite and evaluated the surface structure and the effects of HA density on the initial cell attachment in vitro of murine calvarial preosteoblasts (MC3T3-EI). Scanning electron microscopy (SEM), atomic force microscopy (AFM) and infrared spectroscopy (FTIR) showed that the HA particles were successfully incorporated into the PLA matrix and located at the surface which is of importance in order to maintain the bioactive effect of the HA particles. SEM and AFM investigation revealed that the HA density (particles/area) as well as surface roughness increased with HA loading concentration (i.e. 5, 10, 15 and 20wt%), which promoted protein adsorption. Furthermore, the presence of HA on the surface enhanced cell spreading, increased the formation of actin stress fibers and significantly improved the expression of vinculin in MC3T3-E1 cells which is a key player in the regulation of cell adhesion. These results suggest the potential utility of PLA/HA composites as biomaterials for use as a bone substitute material and in tissue engineering applications.
authors.affiliation: Department of Anatomy and Cell Biology, University of Oulu, FI-90014 Oulu, Finland; Medical Research Center Oulu, FI-90014 Oulu, Finland. Electronic address: Maria.Persson@oulu.fi.
authors.forename: Maria
authors.initials: M
authors.lastname: Persson
authors.affiliation: Department of Anatomy and Cell Biology, University of Oulu, FI-90014 Oulu, Finland.
authors.forename: Gabriela S
authors.initials: GS
authors.lastname: Lorite
authors.affiliation: Department of Anatomy and Cell Biology, University of Oulu, FI-90014 Oulu, Finland.
authors.forename: Hanna E
authors.initials: HE
authors.lastname: Kokkonen
authors.affiliation: School of Engineering, University of Borås, SE-501 90 Borås, Sweden.
authors.forename: Sung-Woo
authors.initials: SW
authors.lastname: Cho
authors.affiliation: Department of Anatomy and Cell Biology, University of Oulu, FI-90014 Oulu, Finland; Medical Research Center Oulu, FI-90014 Oulu, Finland.
authors.forename: Petri P
authors.initials: PP
authors.lastname: Lehenkari
authors.affiliation: School of Engineering, University of Borås, SE-501 90 Borås, Sweden.
authors.forename: Mikael
authors.initials: M
authors.lastname: Skrifvars
authors.affiliation: Department of Anatomy and Cell Biology, University of Oulu, FI-90014 Oulu, Finland; Medical Research Center Oulu, FI-90014 Oulu, Finland.
authors.forename: Juha
authors.initials: J
authors.lastname: Tuukkanen
mesh_terms: D000327:Adsorption; D000818:Animals; D001672:Biocompatible Materials / Q000494:pharmacology*; D001798:Blood Proteins / Q000378:metabolism; D002448:Cell Adhesion / Q000187:drug effects; D002452:Cell Count; D002465:Cell Movement / Q000187:drug effects; D049109:Cell Proliferation / Q000187:drug effects; D048430:Cell Shape / Q000187:drug effects; D017886:Durapatite / Q000494:pharmacology*; D022001:Focal Adhesions / Q000187:drug effects / Q000378:metabolism*; D019344:Lactic Acid / Q000494:pharmacology*; D051379:Mice; D010006:Osteoblasts / Q000166:cytology* / Q000187:drug effects; D011091:Polyesters; D011108:Polymers / Q000494:pharmacology*; D017550:Spectroscopy, Fourier Transform Infrared; D013499:Surface Properties; D013818:Thermogravimetry; D016596:Vinculin / Q000378:metabolism
chemical_list: D001672:Biocompatible Materials; D001798:Blood Proteins; D011091:Polyesters; D011108:Polymers; D016596:Vinculin; D019344:Lactic Acid; C033616:poly(lactide); D017886:Durapatite
keywords: Cell attachment; Focal adhesion; Hydroxyapatite composite; Poly(lactic acid); Surface roughness