Supramolecularly co-assembled composite bone cement prepared from tea polyphenol-modified tricalcium...

Injectable bone cements are widely applied in orthopedic repair, yet their effectiveness is limited by inadequate immune modulation and antimicrobial activity. Here, we developed a multifunctional bone cement (TTKS) by modifying tricalcium phosphate (TP-TCP, TTK) with tea polyphenols (TP) through supramolecular co-assembly and blending it with tricalcium silicate (C₃S) at an 8:2 ratio. The incorporation of tea polyphenols imparted sustained-release capability, antimicrobial activity, immunomodulatory effects, and osteogenic potential. In vitro, TTKS exhibited good cytocompatibility with osteoblasts (MC3T3-E1) and macrophages (RAW264.7), enhanced osteoblast proliferation, migration, and mineralized matrix deposition, and upregulated osteogenic markers (ALP, BMP-2, RUNX-2, OPN). TTKS effectively inhibited methicillin-resistant Staphylococcus aureus (MRSA) colonization by inducing a reactive oxygen species (ROS) burst, leading to bacterial DNA damage. Moreover, TTKS facilitated M2 macrophage polarization and enhanced the secretion of anti-inflammatory cytokines TGF-β1 and IL-10. In a rat cranial defect model, comprehensive evaluation through micro-CT scanning, H&E staining, and Masson's trichrome staining revealed that TTKS significantly promoted bone regeneration and defect repair over a 6-week implantation period. These results demonstrate that TTKS integrates osteogenic, antimicrobial, and immunomodulatory functions, providing a promising platform for bone defect repair and orthopedic applications.