The Role of Cell Seeding, Bioscaffolds, and the In Vivo Microenvironment in the Guided Generation of Osteochondral Composite Tissue.

Tissue engineering based on cell seeding, bioscaffolds, and growth factors has been widely applied for the reconstruction of tissue defects. Recent progress has fueled in vivo tissue engineering techniques in becoming hot topics in regenerative medicine and reconstructive surgery. To improve the efficacy of tissue engineering, we here investigated the roles of cell seeding, bioscaffolds, growth factors, and in vivo microenvironment (IM) in tissue regeneration. Bone marrow-derived stem cells, allogeneic demineralized bone matrix as bioscaffold, and growth factor bone morphogenetic protein 2/transforming growth factor, and the IM of rib periosteum and perichondrium were used in different combinations for the generation of osteochondral composite tissue. Self-regenerated neocomposite tissue based on the IM alone exhibited excellent anatomical configuration, vascularization, biomechanical stability, and function similar to native controls. Our findings indicate that the IM is a crucial factor in biofunctional tissue generation. Further refinement and development of this technique may enable transfer to clinical application with broad spectrum of application.