摘要Periodontal bone regeneration is a major challenge in the treatment of periodontitis.Currently the main obstacle is the difficulty of restoring the regenerative vitality of periodontal osteoblast lineages suppressed by inflammation,via conventional treatment.CD301b+macrophages were recently identified as a subpopulation that is characteristic of a regenerative environment,but their role in periodontal bone repair has not been reported.The current study indicates that CD301b+macrophages may be a constituent component of periodontal bone repair,and that they are devoted to bone formation in the resolving phase of periodontitis.Transcriptome sequencing suggested that CD301b+macrophages could positively regulate osteogenesis-related processes.In vitro,CD301b+macrophages could be induced by interleukin 4(IL-4)unless proinflammatory cytokines such as interleukin 1β(IL-1β)and tumor necrosis factor α(TNF-α)were present.Mechanistically,CD301b+macrophages promoted osteoblast differentiation via insulin-like growth factor 1(IGF-1)/thymoma viral proto-oncogene 1(Akt)/mammalian target of rapamycin(mTOR)signaling.An osteogenic inducible nano-capsule(OINC)consisting of a gold nanocage loaded with IL-4 as the"core"and mouse neutrophil membrane as the"shell"was designed.When injected into periodontal tissue,OINCs first absorbed proinflammatory cytokines in inflamed periodontal tissue,then released IL-4 controlled by far-red irradiation.These events collectively promoted CD301b+macrophage enrichment,which further boosted periodontal bone regeneration.The current study highlights the osteoinductive role of CD301b+macrophages,and suggests a CD301b+macrophage-targeted induction strategy based on biomimetic nano-capsules for improved therapeutic efficacy,which may also provide a potential therapeutic target and strategy for other inflammatory bone diseases.