title: Ectopic bone formation by 3D porous calcium phosphate-Ti6Al4V hybrids produced by perfusion electrodeposition.
abstract: Successful clinical repair of non-healing skeletal defects requires the use of bone substitutes with robust bone inductivity and excellent biomechanical stability. Thus, three-dimensionally functionalised porous calcium phosphate-Ti6Al4V (CaP-Ti) hybrids were produced by perfusion electrodeposition, and the in vitro and in vivo biological performances were evaluated using human periosteum derived cells (hPDCs). By applying various current densities at the optimised deposition conditions, CaP coatings with sub-micrometer to nano-scale porous crystalline structures and different ion dissolution kinetics were deposited on the porous Ti6Al4V scaffolds. These distinctive physicochemical properties caused a significant impact on in vitro proliferation, osteogenic differentiation, and matrix mineralisation of hPDCs. This includes a potential role of hPDCs in mediating osteoclastogenesis for the resorption of CaP coatings, as indicated by a significant down-regulation of osteoprotegerin (OPG) gene expression and by the histological observation of abundant multi-nucleated giant cells near to the coatings. By subcutaneous implantation, the produced hybrids induced ectopic bone formation, which was highly dependent on the physicochemical properties of the CaP coating (including the Ca(2+) dissolution kinetics and coating surface topography), in a cell density-dependent manner. This study provided further insight on stem cell-CaP biomaterial interactions, and the feasibility to produced bone reparative units that are predictively osteoinductive in vivo by perfusion electrodeposition technology.
authors.affiliation: Laboratory for Skeletal Development and Joint Disorders, KU Leuven, O&N 1, Herestraat 49, Bus 813, 3000 Leuven, Belgium. yokechin.chai@med.kuleuven.be
authors.forename: Yoke Chin
authors.initials: YC
authors.lastname: Chai
authors.forename: Greet
authors.initials: G
authors.lastname: Kerckhofs
authors.forename: Scott J
authors.initials: SJ
authors.lastname: Roberts
authors.forename: Simon
authors.initials: S
authors.lastname: Van Bael
authors.forename: Evert
authors.initials: E
authors.lastname: Schepers
authors.forename: Jozef
authors.initials: J
authors.lastname: Vleugels
authors.forename: Frank P
authors.initials: FP
authors.lastname: Luyten
authors.forename: Jan
authors.initials: J
authors.lastname: Schrooten
mesh_terms: D000497:Alloys; D001483:Base Sequence; D001846:Bone Development; D002130:Calcium Phosphates / Q000737:chemistry*; D002454:Cell Differentiation; D049109:Cell Proliferation; D002478:Cells, Cultured; D017931:DNA Primers; D015536:Down-Regulation; D055664:Electrochemical Techniques; D006801:Humans; D008855:Microscopy, Electron, Scanning; D053244:Osteoprotegerin / Q000235:genetics; D016133:Polymerase Chain Reaction; D012995:Solubility; D013499:Surface Properties; D014025:Titanium / Q000737:chemistry*; D014057:Tomography, X-Ray Computed
chemical_list: D000497:Alloys; D002130:Calcium Phosphates; D017931:DNA Primers; D053244:Osteoprotegerin; C031462:titanium alloy (TiAl6V4); C020243:calcium phosphate; D014025:Titanium