Osteogenic Differentiation of Bone Marrow Stromal Cells Induced by Coculture with Chondrocytes Encapsulated in Three-Dimensional Matrices

Abstract

Endochondral ossification implicates chondrocyte signaling as an important factor in directing the osteogenic differentiation of mesenchymal stem cells in vivo. In this study, the osteoinductive capabilities of articular chondrocytes suspended in alginate hydrogels were analyzed via coculture with bone marrow stromal cells (BMSCs). In particular, the effect of chondrocyte coculture time on the mechanism underlying this osteogenic induction was examined. Chondrocytes were suspended in alginate beads and cultured above BMSCs in monolayer. Beads containing chondrocytes were removed after 1, 10, or 21 days of coculture. Quantitative reverse transcriptase polymerase chain reaction was used to assess the expression of alkaline phosphatase, bone morphogenetic protein-2, and osteocalcin by BMSCs after days 1, 8, 14, and 21. Calcium deposition was also assayed to characterize the extent of mineralization within cultures. Results indicate that osteogenic differentiation of BMSCs is initiated upon brief exposure to chondrocyte signaling, but requires continued exposure in order to progress fully and maintain an osteoblastic phenotype.

Coculture Strategies in Bone Tissue Engineering: The Impact of Culture Conditions on Pluripotent Stem Cell Populations

“…The physically distinct locations of the cell populations help track individual phenotype changes and gene expression characteristics. [21][22][23]27,35 The shared media volume also aids in accounting for factors that may be constitutively expressed by one or more of the cell populations, as well as for any temporal changes in the secretory protein expression profile that is typical of many primary cell populations involved in tissue regeneration.…”

“…These covariant factors demonstrate the potential of chemical cross talk that causes differentiation and subsequent production of important matrix-related factors. 21 It is evident from the literature that paracrine signaling between progenitor cells and differentiated cell types provides an excellent starting point for developing therapeutic applications in injury and defect repair. 4,44 Ex vivo cocultures.…”

“…8 The indirect coculture of similar cells has been shown to yield different results in a number of other studies, raising the need for a consensus on the role of factors in the engineering of mineralized bone tissue and their occurrence as a function of the method used. [21][22][23] Through the course of this review, we attempt to present a synthesis of outcomes of coculture strategies in bone tissue engineering and how recent advancements can be applied to further our understanding of molecular interactions, and, finally, to succeed in the ultimate goal of engineering viable bone tissue (Fig. 1).…”

Differentiation of bone marrow-derived mesenchymal stem cells into chondrocytes using chondrocyte extract

“…Compared with fibroblasts, adult stem cells have a broad prospect of application as a result of their potential of multi-directional differentiation into cells including adipocytes, osteoblasts and chondrocytes in response to lineage-specific induction factors (6,7). Bone marrow-derived mesenchymal stem cells (BM-MSCs), widely used in regenerative medicine, have also been successfully induced into chondrocytes by the induction of growth factors (8,9), co-culturing with chondrocytes (10,11) or low-intensity ultrasound (12).…”

Efficacy and Safety of Autologous Cell Therapies for Knee Cartilage Defects (Autologous Stem Cells, Chondrocytes or the Two): Randomized Controlled Trial Design

“…Further, articular chondrocytes have been shown to initiate and drive the osteo-chondrogenic differentiation of BM-MSCs in in vitro coculture systems [27][28][29]. In addition, BM-MSCs have been suggested an appropriate choice of cell for treating larger, osteoarthritic defects [30] as they have both osteogenic and chondrogenic differentiation capability [31][32][33] and have shown encouraging results in generating both tissue types in large animal models of osteochondral injury [34].…”