Bioactive Mineralized Cell-Derived Extracellular Matrix via Polymer-Induced Liquid Precursor Enhances Osteogenesis and Bone Regeneration.

Effective bone regeneration requires biomaterials that exhibit appropriate bioactive functions, particularly osteoconductive and osteoinductive properties. Here, we engineered a cell-derived, decellularized extracellular matrix (cdECM) into a novel mineralized ECM scaffold by harnessing the polymer-induced liquid precursor (PILP) process, an effective strategy for generating calcium phosphate (CaP) mineralized constructs. Mineral deposition within cdECM was successfully achieved through the PILP mineralization, which stabilizes the amorphous precursor phase and promotes matrix-associated mineralization. The resulting mineralized ECM (mECM) exhibited osteoconductive properties, as evidenced by excellent cytocompatibility and enhanced cell proliferation of osteogenic cells. The mECM also demonstrated osteoinductive potential, as confirmed by enhanced alkaline phosphatase activity, increased calcification, and up-regulated osteogenic gene expression in mouse preosteoblasts and human mesenchymal stem cells. Moreover, mECM promoted M2-like macrophage polarization and enhanced tubular formation of endothelial cells. To enable localized in vivo delivery of both ECM-derived biological cues and minerals, a sheet-type mECM scaffold was fabricated using hyaluronic acid as a supporting matrix and further stabilized by glutaraldehyde vapor crosslinking. In a mouse calvarial defect model, the mECM sheet facilitated new bone formation and supported advanced bone maturation, accompanied by enhanced angiogenesis and an M2-dominant anti-inflammatory milieu at an early time point. Collectively, our findings demonstrate that PILP mineralization can be successfully applied to cdECM for generating a bioactive mECM scaffold with enhanced regenerative capacity, representing a promising biomaterial platform for bone tissue regeneration.