Chondrogenesis of human bone marrow‐derived mesenchymal stem cells in agarose culture

AbstractMesenchymal stem cells derived from human bone marrow (hBM‐MSCs) can differentiate into chondrogenic cells for the potential treatment of injured articular cartilage. To evaluate agarose gels as a supportive material for chondrogenesis of hBM‐MSCs, this study examined chondrogenesis of hBM‐MSCs in the agarose cultures. Pellet cultures were employed to confirm the chondrogenic potential of the hBM‐MSCs that were used in agarose cultures. The hBM‐MSCs were seeded in 2% agarose constructs at the initial cell‐seeding densities of 3, 6, and 9 × 106 cells/ml while each of pellets was formed using 2.5 × 105 cells. Chondrogenesis of hBM‐MSCs was induced by culturing cell‐agarose constructs and pellets for 21 days in the presence of a defined medium containing transforming growth factor β3 (TGF‐β3). The analysis of reverse transcription‐polymerase chain reaction showed that hBM‐MSCs of agarose and pellet cultures expressed the chondrogenic markers of collagen type II and aggrecan in the presence of TGF‐β3. The deposition of cartilage‐specific macromolecules was detected in both agarose and pellet cultures by histological and immunohistochemical assessments. Chondrogenesis of hBM‐MSCs in agarose gels directly correlated with the initial cell‐seeding density, with the cell‐agarose constructs of higher initial cell‐seeding density exhibiting more cartilage‐specific gene expressions. This study establishes a basic model for future studies on chondrogenesis of hBM‐MSCs using the agarose cultures. Anat Rec Part A 278A:428–436, 2004. © 2004 Wiley‐Liss, Inc.