Annals of Biomedical Engineering

, Volume 42, Issue 12, pp 2562–2576 | Cite as

Initial Boost Release of Transforming Growth Factor-β3 and Chondrogenesis by Freeze-Dried Bioactive Polymer Scaffolds

  • Jan Philipp Krüger
  • Isabel Machens
  • Matthias Lahner
  • Michaela Endres
  • Christian KapsEmail author


In cartilage regeneration, bio-activated implants are used in stem and progenitor cell-based microfracture cartilage repair procedures. Our aim was to analyze the chondrogenic potential of freeze-dried resorbable polymer-based polyglycolic acid (PGA) scaffolds bio-activated with transforming growth factor-β3 (TGFB3) on human subchondral mesenchymal progenitor cells known from microfracture. Progenitor cells derived from femur heads were cultured in the presence of freeze-dried TGFB3 in high-density pellet culture and in freeze-dried TGFB3-PGA scaffolds for chondrogenic differentiation. Progenitor cell cultures in PGA scaffolds as well as pellet cultures with and without continuous application of TGFB3 served as controls. Release studies showed that freeze-dried TGFB3-PGA scaffolds facilitate a rapid, initial boost-like release of 71.5% of TGFB3 in the first 10 h. Gene expression analysis and histology showed induction of typical chondrogenic markers like type II collagen and formation of cartilaginous tissue in TGFB3-PGA scaffolds seeded with subchondral progenitor cells and in pellet cultures stimulated with freeze-dried TGFB3. Chondrogenic differentiation in freeze-dried TGFB3-PGA scaffolds was comparable to cultures receiving TGFB3 continuously, while non-stimulated controls did not show chondrogenesis during prolonged culture for 14 days. These results suggest that bio-activated, freeze-dried TGFB3-PGA scaffolds have chondrogenic potential and are a promising tool for stem cell-mediated cartilage regeneration.


Cartilage tissue engineering Cartilage regeneration Resorbable polymer scaffold Polyglycolic acid Chondrocyte differentiation Freeze-drying Growth factor release 



The authors are very grateful to Samuel Vetterlein for the excellent technical assistance. JPK, ME and CK are employees of TransTissue Technologies GmbH. TransTissue develops products on the basis of polymer-scaffolds for the regeneration of mesenchymal tissues. This study was supported by the European Union, EU-FP7 program (TissueGEN: HEALTH-F4-2011-278955).


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Copyright information

© Biomedical Engineering Society 2014

Authors and Affiliations

  • Jan Philipp Krüger
    • 1
  • Isabel Machens
    • 1
  • Matthias Lahner
    • 2
  • Michaela Endres
    • 1
    • 3
  • Christian Kaps
    • 1
    • 3
    Email author
  1. 1.TransTissue Technologies GmbHBerlinGermany
  2. 2.Department of Orthopaedic Sports Surgery, St. Josef-HospitalRuhr-University BochumBochumGermany
  3. 3.Tissue Engineering Laboratory, Department of RheumatologyCharité - Universitätsmedizin BerlinBerlinGermany

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