title: Mesenchymal stem cells from osteoporotic patients reveal reduced migration and invasion upon stimulation with BMP-2 or BMP-7.
abstract: Fractures to the osteoporotic bone feature a delay in callus formation and reduced enchondral ossification. Human mesenchymal stem cells (hMSC), the cellular source of fracture healing, are recruited to the fracture site by cytokines, such as BMP-2 and BMP-7. Aim of the study was to scrutinize hMSC for osteoporosis associated alterations in BMP mediated migration and invasion as well as in extracellular matrix (ECM) binding integrin expression. HMSC were isolated from 18 healthy or osteoporotic donors. Migration was assessed using a collagen IV coated micro-slide linear gradient chamber and time-lapse microscopy. Invasion was analyzed utilizing an ECM coated transmembrane invasion assay. Quantitative real-time RT PCR was performed for the ECM binding integrins α1, α2, α3, α4, α5, α11, αv and β1. HMSC from osteoporotic patients showed a significant increase of migration upon BMP-2 or FCS stimulation, as well as a significant increase of invasion upon BMP-2, BMP-7 or FCS stimulation. Nevertheless, the migration and invasion capacity was significantly decreased compared to healthy controls. Out of all integrins analyzed, collagen binding integrin α2 was significantly downregulated in hMSC from osteoporotic patients. In conclusion, we here demonstrate for the first time osteoporosis associated alterations in BMP mediated hMSC recruitment. These findings may underlie the reduced healing of osteoporotic fractures. Nevertheless, the maintained migration and invasion response upon BMP stimulation illustrates the therapeutic potential of these clinically approved substances in the treatment of osteoporotic fractures. Another therapeutic target may be the downregulation of the collagen binding integrin α2 in hMSC from osteoporotic patients.
authors.affiliation: Experimental Surgery and Regenerative Medicine, Department of Hand-, Plastic- and Trauma Surgery, Ludwig-Maximilians-University (LMU), Nussbaumstr. 20, D-80336 Munich, Germany. Electronic address: florian.haasters@med.uni-muenchen.de.
authors.forename: Florian
authors.initials: F
authors.lastname: Haasters
authors.affiliation: Experimental Surgery and Regenerative Medicine, Department of Hand-, Plastic- and Trauma Surgery, Ludwig-Maximilians-University (LMU), Nussbaumstr. 20, D-80336 Munich, Germany. Electronic address: denitsa.docheva@med.uni-muenchen.de.
authors.forename: Denitsa
authors.initials: D
authors.lastname: Docheva
authors.affiliation: Experimental Surgery and Regenerative Medicine, Department of Hand-, Plastic- and Trauma Surgery, Ludwig-Maximilians-University (LMU), Nussbaumstr. 20, D-80336 Munich, Germany. Electronic address: gassner.cj@gmail.com.
authors.forename: Christoph
authors.initials: C
authors.lastname: Gassner
authors.affiliation: Experimental Surgery and Regenerative Medicine, Department of Hand-, Plastic- and Trauma Surgery, Ludwig-Maximilians-University (LMU), Nussbaumstr. 20, D-80336 Munich, Germany. Electronic address: tzvetan.popov@med.uni-muenchen.de.
authors.forename: Cvetan
authors.initials: C
authors.lastname: Popov
authors.affiliation: Experimental Surgery and Regenerative Medicine, Department of Hand-, Plastic- and Trauma Surgery, Ludwig-Maximilians-University (LMU), Nussbaumstr. 20, D-80336 Munich, Germany. Electronic address: wboecker@me.com.
authors.forename: Wolfgang
authors.initials: W
authors.lastname: Böcker
authors.affiliation: Experimental Surgery and Regenerative Medicine, Department of Hand-, Plastic- and Trauma Surgery, Ludwig-Maximilians-University (LMU), Nussbaumstr. 20, D-80336 Munich, Germany. Electronic address: wolf.mutschler@med.uni-muenchen.de.
authors.forename: Wolf
authors.initials: W
authors.lastname: Mutschler
authors.affiliation: Experimental Surgery and Regenerative Medicine, Department of Hand-, Plastic- and Trauma Surgery, Ludwig-Maximilians-University (LMU), Nussbaumstr. 20, D-80336 Munich, Germany. Electronic address: matthias.schieker@med.uni-muenchen.de.
authors.forename: Matthias
authors.initials: M
authors.lastname: Schieker
authors.affiliation: Experimental Surgery and Regenerative Medicine, Department of Hand-, Plastic- and Trauma Surgery, Ludwig-Maximilians-University (LMU), Nussbaumstr. 20, D-80336 Munich, Germany. Electronic address: christian.prall@med.uni-muenchen.de.
authors.forename: Wolf Christian
authors.initials: WC
authors.lastname: Prall
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D055396:Bone Morphogenetic Protein 2 / Q000502:physiology*; D055419:Bone Morphogenetic Protein 7 / Q000502:physiology*; D016022:Case-Control Studies; D002465:Cell Movement; D006801:Humans; D059630:Mesenchymal Stem Cells / Q000473:pathology*; D010024:Osteoporosis / Q000473:pathology*; D060888:Real-Time Polymerase Chain Reaction
chemical_list: D055396:Bone Morphogenetic Protein 2; D055419:Bone Morphogenetic Protein 7
keywords: Integrin expression; Invasion; Mesenchymal stem cells (MSC); Migration