We used human fetal bone marrow-derived mesenchymal stromal cells (hfMSCs) differentiating towards chondrocytes as an
alternative model for the human growth plate (GP). Our aims were to study gene expression patterns associated with
chondrogenic differentiation to assess whether chondrocytes derived from hfMSCs are a suitable model for studying the
development and maturation of the GP. hfMSCs efficiently formed hyaline cartilage in a pellet culture in the presence of
TGFb3 and BMP6. Microarray and principal component analysis were applied to study gene expression profiles during
chondrogenic differentiation. A set of 232 genes was found to correlate with in vitro cartilage formation. Several identified
genes are known to be involved in cartilage formation and validate the robustness of the differentiating hfMSC model.
KEGG pathway analysis using the 232 genes revealed 9 significant signaling pathways correlated with cartilage formation.
To determine the progression of growth plate cartilage formation, we compared the gene expression profile of
differentiating hfMSCs with previously established expression profiles of epiphyseal GP cartilage. As differentiation towards
chondrocytes proceeds, hfMSCs gradually obtain a gene expression profile resembling epiphyseal GP cartilage. We
visualized the differences in gene expression profiles as protein interaction clusters and identified many protein clusters that
are activated during the early chondrogenic differentiation of hfMSCs showing the potential of this system to study GP