title: Mineralised collagen--an artificial, extracellular bone matrix--improves osteogenic differentiation of bone marrow stromal cells.
abstract: In the field of bone tissue engineering there is a high demand on bone graft materials which promote bone formation. By combination of collagen type I with nanocrystalline hydroxyapatite (HA) we generated a resorbable material which structure and composition is close to those of the extracellular bone matrix. This nanocomposite material was produced in a biomimetic process in which collagen fibril assembly and mineralisation with hydroxyapatite occur simultaneously. In this study the proliferation and osteogenic differentiation of human bone marrow-derived stromal cells (hBMSC) on membranes of biomimetically mineralised collagen type I was investigated. To this end, we optimised biochemical assays for determination of cell number and alkaline phosphatase activity corresponding to the special properties of this biomaterial. For cell experiments hBMSC were seeded on the mineralised collagen membranes and cultivated over 35 days, both in static and perfusion culture, in the presence and absence of dexamethasone, beta-glycerophosphate and ascorbate. Compared to cells grown on tissue culture polystyrene we found attenuated proliferation rates, but markedly increased activity of alkaline phosphatase on the mineralised collagen indicating its promoting effect on the osteogenic differentiation of hBMSC. Therefore this bone-like material may act as a suitable artificial extracellular matrix for bone tissue engineering. Perfusion of the 2D cell matrix constructs with cell culture medium did not improve proliferation and osteogenic differentiation of the hBMSC.
authors.affiliation: Max Bergmann Center of Biomaterials, Institute of Materials Science, Technische Universität Dresden, Budapester-Str. 27, 01069 Dresden, Germany. bernhard@tmfs.mpgfk.tu-dresden.de
authors.forename: Anne
authors.initials: A
authors.lastname: Bernhardt
authors.forename: Anja
authors.initials: A
authors.lastname: Lode
authors.forename: Sabine
authors.initials: S
authors.lastname: Boxberger
authors.forename: Wolfgang
authors.initials: W
authors.lastname: Pompe
authors.forename: Michael
authors.initials: M
authors.lastname: Gelinsky
mesh_terms: D001672:Biocompatible Materials / Q000737:chemistry*; D032701:Biomimetics; D001854:Bone Marrow Cells / Q000166:cytology; D018786:Bone Substitutes; D001842:Bone and Bones / Q000737:chemistry*; D002454:Cell Differentiation; D002462:Cell Membrane / Q000378:metabolism; D049109:Cell Proliferation; D003094:Collagen / Q000737:chemistry*; D005109:Extracellular Matrix / Q000737:chemistry*; D006801:Humans; D008855:Microscopy, Electron, Scanning; D017154:Stromal Cells / Q000166:cytology; D013997:Time Factors; D023822:Tissue Engineering / Q000379:methods*
chemical_list: D001672:Biocompatible Materials; D018786:Bone Substitutes; D003094:Collagen