3D-printed HAp bone regeneration scaffolds enable nano-scale manipulation of cellular mechanotransduction signals

Nano-scale morphology on bone tissue engineering scaffold plays an essential role in cell behavior regulation and bone regeneration. In this study, patient-customized porous bone tissue engineering scaffolds were fabricated by 3D printing. Then functionalized nanorod morphologies were controllably fabricated. The influence of nanorods geometrical cues on cellular behaviors and the mechanics of triggered osteogenesis were studied. In vitro studies indicated that the nanorods with a diameter of 30 nm accelerated cell proliferation and osteogenic differentia-tion. Yes-associated protein (YAP) was found involved in the cell sensing system, which regulates the cytoskeletal structure and gene expression. These results provided strong evidence that the surface nano-scale morphology triggered mechanotransduction related signals for promoting osteogenic differentiation. In vivo experiments indicated that the proposed 3D printed scaffolds with a nanorod coating promoted bone regeneration without exogenous cells and growth factors. This work provides a promising strategy for personalized bone tissue repair.