gms | German Medical Science

Deutscher Kongress für Orthopädie und Unfallchirurgie
70. Jahrestagung der Deutschen Gesellschaft für Unfallchirurgie
92. Tagung der Deutschen Gesellschaft für Orthopädie und Orthopädische Chirurgie und
47. Tagung des Berufsverbandes der Fachärzte für Orthopädie

02. - 06.10.2006, Berlin

Biocompatibility of super-paramagnetic nanoparticles and its effect on the osteogenic differentiation of mesenchymal stem cells

Meeting Abstract

  • A. Mehlhorn - Department of Orthopaedic and Trauma Surgery, Alberts-Ludwigs University Freiburg, Freiburg, Germany
  • K. Utchiyama - Department of Orthopaedic and Trauma Surgery, Alberts-Ludwigs University Freiburg, Freiburg, Germany
  • H. Schmal - Department of Orthopaedic and Trauma Surgery, Alberts-Ludwigs University Freiburg, Freiburg, Germany
  • A. Petri-Fink - Powder Institute of Material Science, EPFL, Lausanne, Switzerland
  • H. Hofmann - Powder Institute of Material Science, EPFL, Lausanne, Switzerland
  • N. Südkamp - Department of Orthopaedic and Trauma Surgery, Alberts-Ludwigs University Freiburg, Freiburg, Germany

Deutscher Kongress für Orthopädie und Unfallchirurgie. 70. Jahrestagung der Deutschen Gesellschaft für Unfallchirurgie, 92. Tagung der Deutschen Gesellschaft für Orthopädie und Orthopädische Chirurgie und 47. Tagung des Berufsverbandes der Fachärzte für Orthopädie. Berlin, 02.-06.10.2006. Düsseldorf, Köln: German Medical Science; 2006. DocE.3.1-1594

Die elektronische Version dieses Artikels ist vollständig und ist verfügbar unter: http://www.egms.de/de/meetings/dgu2006/06dgu0079.shtml

Veröffentlicht: 28. September 2006

© 2006 Mehlhorn et al.
Dieser Artikel ist ein Open Access-Artikel und steht unter den Creative Commons Lizenzbedingungen (http://creativecommons.org/licenses/by-nc-nd/3.0/deed.de). Er darf vervielf&aauml;ltigt, verbreitet und &oauml;ffentlich zug&aauml;nglich gemacht werden, vorausgesetzt dass Autor und Quelle genannt werden.


Gliederung

Text

The development of super-paramagnetic nanoparticles opens new possibilities for directed growth factor delivery to enhance healing of bone defects. Proteins or plasmids (pDNA) can be coupled to super-paramagnetic nanoparticles (SPION), be directed to intra- or extracellular targets and then be released by magnetic force e.g. an intermittent magnetic field. Since SPION have been developed recently there are only a few data about the influence of nanoparticles on cellular proliferation and differentiation. As a first step to use nanoparticles for biomedical purposes we examined the biocompatibility of plain coated SPION and its effect on osteogenic differentiation in vitro.

Osteogenic precursor cells (MC3T3) and mesenchymal stem cells (C3H10T1/2) were cultured in presence or absence of amnio-polyvinylalcohol- (aPVA) and carboxy-polyvinylalcohol- (cPVA) coated SPION for 1h, 4h, 4d or 6d. The samples were stimulated in a static or intermittent magnetic field (1Hz, 1 or 4 h/d). The intracellular iron content, the cellular proliferation and the expression of bone specific alkaline phosphatase were measured and Cy-3 labelled SPION were detected by confocal laser scanning microscopy. The staining of the actin skeleton, focal adhesions (vinculin/paxillin) and calcified matrix was performed.

It was shown that the coating of SPION with aPVA enables and with cPVA inhibits the intracellular uptake of the SPION by changing of the particle load. In presence of SPION (intermittent magnetic field, 4h) an enhancement of actin skeleton and a weakening of focal adhesions was observed. Beside this, no morphological changes were found. In presence of a static magnetic field the particles seemed not to have any effect on cellular proliferation and differentiation. In presence of an intermittent magnetic field a decrease of proliferation in all groups (p<0.05) and an increase of DNA content in cPVA-SPION groups (p<0.05) was observed. The alkaline phosphatase activity per µg DNA was decreased in cPVA-SPION groups.

SPION have been shown to deliver proteins or pDNA to cellular targets. In absence of magnetic fields particles seem not to change the cellular properties of MC3T3 and C3H10T1/2 cells. In presence of an intermittent magnetic field SPION might change proliferation and differentiation properties depending on the surface coating and the used frequency. In future delivery- and release-mechanisms of SPION-coupled proteins or pDNA have to be examined to develop SPION-based applications for the clinical use.