FIG. 3.

Therapeutic strategies for cartilage damage utilizing preconditioned stem cell and three-dimensional (3D) matrix. After ex vivo expansion of adult stem cells extracted from the human body, two strategies can be used for the treatment of cartilage defects: direct intra-articular injection or transplant of cells in a 3D scaffold. For full-thickness cartilage defects, the second strategy is normally used. Three-dimensional scaffolds can be made of extracellular matrix (ECM) materials. A structurally and mechanically stable scaffold allows for infiltration and attachment of bioactive molecules (IGF-I, FGF-2, and/or TGF-β), which can exert their anti-inflammatory effects on the surrounding environment. For partial-thickness cartilage defects, direct intra-articular injection of expanded stem cells is an option. Mesenchymal stem cells can secrete growth factors, which may exert their anti-inflammatory and antioxidative effects in the microenvironment where mesenchymal stem cells (MSCs) reside. These growth factors also benefit tissue regeneration. A recent finding suggests that decellularized stem cell matrix (DSCM) could rejuvenate expanded MSCs in proliferation and chondrogenic potential; this process may provide a large quantity of high-quality MSCs for cell-based cartilage regeneration. DSCM-expanded MSCs exhibiting an enhanced capacity against oxidation and inflammation may represent a promising anti-inflammatory strategy in the near future. Color images available online at www.liebertpub.com/teb