Local stimulation of articular cartilage repair by transplantation of encapsulated chondrocytes overexpressing human fibroblast growth factor 2 (FGF-2) in vivo

Gunter Kaul, Magali Cucchiarini, David Arntzen, David Zurakowski, Michael D. Menger, Dieter Kohn, Stephen B. Trippel, Henning Madry

Research output: Contribution to journalArticle

82 Scopus citations


Background: Defects of articular cartilage are an unsolved problem in orthopaedics. In the present study, we tested the hypothesis that gene transfer of human fibroblast growth factor 2 (FGF-2) via transplantation of encapsulated genetically modified articular chondrocytes stimulates chondrogenesis in cartilage defects in vivo. Methods: Lapine articular c hondrocytes overexpressing a lacZ or a human FGF-2 gene sequence were encapsulated in alginate and further characterized. The resulting lacZ or FGF-2 spheres were applied to cartilage defects in the knee joints of rabbits. In vivo, cartilage repair was assessed qualitatively and quantitatively at 3 and 14 weeks after implantation. Results: In vitro, bioactive FGF-2 was secreted, leading to a significant increase in the cell numbers in FGF-2 spheres. In vivo, FGF-2 continued to be expressed for at least 3 weeks without leading to differences in FGF-2 concentrations in the synovial fluid between treatment groups. Histological analysis revealed no adverse pathologic effects on the synovial membrane at any time point. FGF-2 gene transfer enhanced type II collagen expression and individual parameters of chondrogenesis, such as the cell morphology and architecture of the new tissue. Overall articular cartilage repair was significantly improved at both time points in vivo. Conclusions: The data suggest that localized overexpression of FGF-2 enhances the repair of cartilage defects via stimulation of chondrogenesis, without adverse effects on the synovial membrane. These results may lead to the development of safe gene-based therapies for human articular cartilage defects.

Original languageEnglish (US)
Pages (from-to)100-111
Number of pages12
JournalJournal of Gene Medicine
Issue number1
StatePublished - Jan 1 2006



  • Alginate
  • Cartilage defects
  • Chondrocytes
  • FGF-2
  • Transfection
  • Transplantation

ASJC Scopus subject areas

  • Genetics

Cite this