title: Biocompatibility of bioresorbable poly(L-lactic acid) composite scaffolds obtained by supercritical gas foaming with human fetal bone cells.
abstract: The aim of this investigation was to test the biocompatibility of three-dimensional bioresorbable foams made of poly(L-lactic acid) (PLA), alone or filled with hydroxyapatite (HA) or beta-tricalcium phosphate (beta-TCP), with human primary osteoblasts, using a direct contact method. Porous constructs were processed by supercritical gas foaming, after a melt-extrusion of ceramic/polymer mixture. Three neat polymer foams, with pore sizes of 170, 310, and 600 microm, and two composite foams, PLA/5 wt% HA and PLA/5 wt% beta-TCP, were examined over a 4-week culture period. The targeted application is the bone tissue-engineering field. For this purpose, human fetal and adult bone cells were chosen because of their highly osteogenic potential. The association of fetal bone cells and composite scaffold should lead to in vitro bone formation. The polymer and composite foams supported adhesion and intense proliferation of seeded cells, as revealed by scanning electron microscopy. Cell differentiation toward osteoblasts was demonstrated by alkaline phosphatase (ALP) enzymatic activity, gamma-carboxylated Gla-osteocalcin production, and the onset of mineralization. The addition of HA or beta-TCP resulted in higher ALP enzymatic activity for fetal bone cells and a stronger production of Gla-osteocalcin for adult bone cells.
authors.affiliation: Laboratoire de Recherche en Orthopédie, Ecole Polytechnique Fédérale de Lausanne, Lausanne, Switzerland.
authors.forename: Marc-Olivier
authors.initials: MO
authors.lastname: Montjovent
authors.forename: Laurence
authors.initials: L
authors.lastname: Mathieu
authors.forename: Boris
authors.initials: B
authors.lastname: Hinz
authors.forename: Lee Laurent
authors.initials: LL
authors.lastname: Applegate
authors.forename: Pierre-Etienne
authors.initials: PE
authors.lastname: Bourban
authors.forename: Pierre-Yves
authors.initials: PY
authors.lastname: Zambelli
authors.forename: Jan-Anders
authors.initials: JA
authors.lastname: Månson
authors.forename: Dominique P
authors.initials: DP
authors.lastname: Pioletti
mesh_terms: D018786:Bone Substitutes; D002130:Calcium Phosphates; D002478:Cells, Cultured; D005333:Fetus / Q000502:physiology* / Q000648:ultrastructure; D006801:Humans; D019344:Lactic Acid; D008422:Materials Testing / Q000379:methods; D010006:Osteoblasts / Q000502:physiology* / Q000648:ultrastructure; D010012:Osteogenesis / Q000502:physiology*; D011091:Polyesters; D011108:Polymers; D023822:Tissue Engineering / Q000379:methods
chemical_list: D018786:Bone Substitutes; D002130:Calcium Phosphates; D011091:Polyesters; D011108:Polymers; C485817:beta-tricalcium phosphate; D019344:Lactic Acid; C033616:poly(lactide)