Oral Presentation Matrix Biology Society of Australia and New Zealand Annual Meeting 2012

FGF-2 and -18 promote chondrogenic and terminal osteogenic differentiation of bone marrow derived chondroprogenitor cells in micromass pellet culture. (#9)

Cindy C Shu 1 , Margaret M Smith 1 , Susan M Smith 1 , Clare E Hughes 2 , Bruce Caterson 2 , Stephen N Hunyor 3 , Chris Ward 4 , Christopher B Little 1 , James Melrose 1
  1. Kolling Institute of Medical Research, St. Leonards, NSW, Australia
  2. School of Biosciences, University of Cardiff, Cardiff, UK
  3. Centre for Cardiac Technology, Kolling Institute of Medical Research, St. Leonards, NSW, Australia
  4. Northern Blood Research Centre and Department of Haematology, Kolling Institute of Medical Research, St. Leonards, NSW, Australia

Bone marrow derived mesenchymal stem cells (BMMSCs) display an enormous potential for cartilage repair.  There is a clear need for such regenerative strategies given the poor regenerative capacity of articular cartilage.  Feedback cues from the extracellular matrix (ECM) via cell-cell and cell-matrix interactions are important for the regulation of BMMSCs. Interaction with soluble factors, other cells and ECM, define a local biochemical/biomechanical regulatory niche promoting stem cell survival, self-renewal and differentiation. FGF-2 and -18 and perlecan can promote chondrocyte proliferation and ECM production in-vitro. The former has been used to stimulate cartilage repair and FGF-18 is undergoing phase III clinical trials for the repair of OA lesions (Merck-Serono). In the present study we examined if FGF-2 and -18 could be used to stimulate chondroprogenitor cells to produce ECM components conducive to cartilage repair.  CD44 and CD106 positive and CD11b, CD34 and CD45 negative ovine BMMSCs were isolated.  Pluripotency was established in chondrogenic, adipogenic and osteogenic selection media.  Seventh passage BMMSCs were grown in pellet culture in chondroselection media for 21 days and then with media supplemented with FGF-2 or FGF-18 (10ng/ml) for a further 21 days. Cartilage ECM components were demonstrated in the pellets by immunohistochemistry, total RNA was also isolated and qRT-PCR undertaken of selected cartilage matrix genes. FGF-2 promoted chondrogenic differentiation of MSCs in micro-mass pellet culture.  Alizarin Red S staining demonstrated calcium deposition centrally in the FGF-18 pellets on day 42 accompanied by up-regulation of perlecan production by cells located at the periphery of the pellets.  In contrast, cells in the vicinity of the central calcium deposition expressed elevated levels of decorin and biglycan substituted with CS chains displaying the developmental CS sulphation motifs 7D4 and 4C3.  This demonstrated for the first time that terminal differentiation of chondrocytes by FGF-18 also induced a subtle modulation of glycosaminoglycan substitution on decorin and biglycan.