A Biomimetic Smart Nanoplatform as "Inflammation Scavenger" for Regenerative Therapy of Periodontal Tissue

Introduction: The functional reconstruction of periodontal tissue defects remains a clinical challenge due to excessive and prolonged host response to various endogenous and exogenous pro-inflammatory stimuli. Thus, a biomimetic nanoplatform with the capability of modulating inflammatory response in a microenvironment-responsive manner is attractive for regenerative therapy of periodontal tissue. Methods: Herein, a facile and green design of engineered bone graft materials was developed by integrating a biomimetic apatite nanocomposite with a smart-release coating, which could realize inflammatory modulation by "on-demand" delivery of the anti-inflammatory agent through a pH-sensing mechanism. Results: In vitro and in vivo experiments demonstrated that this biocompatible nanoplatform could facilitate the clearance of reactive oxygen species in human periodontal ligament stem cells under inflammatory conditions via inhibiting the production of endogenous proinflammatory mediators, in turn contributing to the enhanced healing efficacy of periodontal tissue. Moreover, this system exhibited effective antimicrobial activity against common pathogenic bacteria in the oral cavity, which is beneficial for the elimination of exogenous pro-inflammatory factors from bacterial infection during healing of periodontal tissue. Conclusion: The proposed strategy provides a versatile apatite nanocomposite as a promising "inflammation scavenger" and propels the development of intelligent bone graft materials for periodontal and orthopedic applications.