Oriented Collagen Scaffolds for Anisotropic Bone Tissue Construction In Vitro

Constructing biomimetic tissue architecture in vitro holds the key to the realization of tissue engineering. To control the anisotropic microstructure of bone tissue which governs the mechanical properties of bone, especially, is imperative for the establishment of ideal bone regeneration process. In this study, highly aligned collagen scaffolds were fabricated to control osteoblast alignment. Collagen fibrillogenesis were regulated by an extrusion process, resulting in formation of biomimetic, hierarchically-aligned bony microstructure. Osteoblasts adhered to the fabricated scaffolds showed aligned morphology along the collagen orientation. In the present method, the degree of scaffold orientation is regulatable, which suggests that the designing of the appropriate scaffolds depending on the tissue anisotropy is possible. Interestingly, the bone matrix produced by the aligned osteoblasts exhibited anisotropic microstructure along the cell alignment. Our findings imply that controlling the osteoblast alignment by oriented collagen scaffolds could be an initiator to establish the anisotropic bone structural development or regeneration.