title: Stromal cell-derived factor-1alpha-directed chemoattraction of transiently CXCR4-overexpressing bone marrow stromal cells into functionalized three-dimensional biomimetic scaffolds.
abstract: Three-dimensional (3D) bone substitute material should not only serve as scaffold in large bone defects but also attract mesenchymal stem cells, a subset of bone marrow stromal cells (BMSCs) that are able to form new bone tissue. An additional crucial step is to attract BMSCs from the surface into deeper structures of 3D porous bone substitute scaffolds. Here we show that transient overexpression of CXCR4 in human BMSCs induced by mRNA transfection enhances stromal cell-derived factor-1alpha (SDF-1alpha)-directed chemotactic capacity to invade internal compartments of porous 3D bone substitute scaffolds in vitro and in vivo. In vitro native BMCSs invaded up to 500 mum into SDF-1alpha-releasing 3D scaffolds, whereas CXCR4-overexpressing BMSCs invaded up to 800 mum within 5 days. In addition, 60% downregulation of endogenous SDF-1 transcription in BMSCs by endoribonuclease-prepared siRNA before CXCR4 mRNA transfection enhanced SDF-1alpha-directed migration of human BMSCs by 50%. Implantation of SDF-1alpha-releasing scaffolds seeded with transiently CXCR4-overexpressing BMSCs resulted in an increase of invasion into internal compartments of the scaffolds in a mouse model. In vivo native BMCS invaded up to 250 mum into SDF-1alpha-releasing 3D scaffolds, whereas CXCR4-overexpressing BMSC invaded up to 500 mum within 5 days. Thus, the SDF-1alpha/CXCR4 chemoattraction system can be used to efficiently recruit BMSCs into SDF-1alpha-releasing 3D scaffolds in vitro and in vivo.
authors.affiliation: Department of Pediatrics, University Clinic Carl Gustav Carus, Technische Universität Dresden , Dresden, Germany.
authors.forename: Sebastian
authors.initials: S
authors.lastname: Thieme
authors.forename: Martin
authors.initials: M
authors.lastname: Ryser
authors.forename: Marcus
authors.initials: M
authors.lastname: Gentsch
authors.forename: Katrin
authors.initials: K
authors.lastname: Navratiel
authors.forename: Sebastian
authors.initials: S
authors.lastname: Brenner
authors.forename: Maik
authors.initials: M
authors.lastname: Stiehler
authors.forename: Jan
authors.initials: J
authors.lastname: Rölfing
authors.forename: Michael
authors.initials: M
authors.lastname: Gelinsky
authors.forename: Angela
authors.initials: A
authors.lastname: Rösen-Wolff
mesh_terms: D000818:Animals; D040761:Biomimetic Materials / Q000494:pharmacology*; D001854:Bone Marrow Cells / Q000166:cytology*; D054377:Chemokine CXCL12 / Q000378:metabolism*; D002633:Chemotaxis / Q000187:drug effects*; D006801:Humans; D051379:Mice; D016513:Mice, SCID; D008855:Microscopy, Electron, Scanning; D016062:Porosity / Q000187:drug effects; D034741:RNA, Small Interfering / Q000378:metabolism; D019718:Receptors, CXCR4 / Q000378:metabolism*; D017154:Stromal Cells / Q000166:cytology / Q000187:drug effects / Q000378:metabolism* / Q000637:transplantation; D054457:Tissue Scaffolds / Q000737:chemistry*; D014162:Transfection
chemical_list: D054377:Chemokine CXCL12; D034741:RNA, Small Interfering; D019718:Receptors, CXCR4