Comparison of the chondrogenic potential of mesenchymal stem cells derived from bone marrow and umbilical cord blood intended for cartilage tissue engineering

International audienceArticular cartilage is frequently altered upon trauma or in osteoarthritis (OA), a degenerative disease that is currently incurable. Cartilage tissue engineering/cell therapy offer new insights to cure these articular disorders. Since the first generation of cartilage tissue engineering led to a poor quality cartilage rich in the hyaline cartilage atypical type I collagen, it has been followed with improved generations. One way to improve these strategies was to diversify the cell type used. Mesenchymal stem cells (MSC) are considered as an interesting cell type in order to produce a hyaline cartilage substitute. This study aimed to compare umbilical cord blood (UCB) and bone marrow (BM) derived MSC. BM and UCB MSC were isolated and then amplified in monolayer culture. We characterized MSC by assessing their proliferative and multipotence capacities, and the presence of cluster of differentiation (CD) characteristic of MSC. Then, we compared MSC at their basal state and after a chondrogenic differentiation, which consisted of culture in hypoxia or normoxia in a biomaterial, with chondrogenic factors (BMP-2, TGF-ß1). Criteria used to compare MSC were the mRNA level and protein amount of several osteogenic (osteocalcin/Runx2), hypertrophic (type X collagen) and chondrogenic markers (type II collagen). Furthermore, we analysed the extracellular matrix(ECM) composition/structure by immunochemistry