Lanthanum phosphate/chitosan scaffolds enhance cytocompatibility and osteogenic efficiency via the Wnt/β-catenin pathway

BACKGROUND: Fabrication of porous scaffolds with great biocompatibility and osteoinductivity to promote bone defect healing has attracted extensive attention. METHODS: In a previous study, novel lanthanum phosphate (LaPO(4))/chitosan (CS) scaffolds were prepared by distributing 40- to 60-nm LaPO(4) nanoparticles throughout plate-like CS films. RESULTS: Interconnected three dimensional (3D) macropores within the scaffolds increased the scaffold osteoconductivity, thereby promoting cell adhesion and bone tissue in-growth. The LaPO(4)/CS scaffolds showed no obvious toxicity and accelerated bone generation in a rat cranial defect model. Notably, the element La in the scaffolds was found to promote osteogenic differentiation of bone marrow mesenchymal stem cells (BMSCs) through the Wnt/β-catenin signalling pathway and induced high expression of the osteogenesis-related genes alkaline phosphatase, osteocalcin and Collagen I (Col-I). Moreover, the LaPO(4)/CS scaffolds enhanced bone regeneration and collagen fibre deposition in rat critical-sized calvarial defect sites. CONCLUSION: The novel LaPO(4)/CS scaffolds provide an admirable and promising platform for the repair of bone defects. ELECTRONIC SUPPLEMENTARY MATERIAL: The online version of this article (10.1186/s12951-018-0411-9) contains supplementary material, which is available to authorized users.