Self-regulated immune-neurovascular bone repair scaffold via functional surface features

Abstract

Given specific microenvironment of bone repair, the novel implant endowed with self-regulated bone healing procedure was the representative trend of bio-functional decoration. Inspired by the microstructure and chemical composition of natural bone, bioactive calcium titanate coating containing trace ions with micro/nano-gradient morphological for bionic human bone was in-situ hydrothermally grown on 3D printed porous titanium alloy scaffold. Surface features on these porous titanium alloy scaffolds, by itself, could modulate microenvironment, and enhance neurovascular bone regeneration and reconstruction via micro/nano-scaled surface topography and bioactive ions of sustainable release, as verified by in vitro and in vivo biological evaluation. The underlying immunoregulation mechanism was simultaneous activation of PPAR and PI3K-Akt-mTOR signaling axes, which advocated M2 macrophage phenotypic switch. It provided an insightful foundation for intelligent implants of self-regulated bone repair.