Characterising the periodontal granulation tissue using scRNAseq.
AimsOur research investigated the cellular composition and molecular mechanisms of periodontal granulation tissue using single-cell RNA sequencing (scRNA-seq), aiming to enhance the understanding of periodontal disease pathogenesis and identify potential targets for regenerative therapies. Materials and MethodsGranulation tissue samples were collected from patients undergoing periodontal surgery. Fresh tissues were processed into single-cell suspensions and subjected to scRNA-seq. The data were integrated with existing datasets from healthy gingiva and periodontal ligament. Computational analyses were performed, and validation through immunofluorescence staining. ResultsTen distinct cell clusters were identified across the samples. Granulation tissue exhibited a higher abundance of immune cells compared to healthy tissues. A novel endothelial cell subpopulation, exclusive to granulation tissue, was discovered, characterized by NOTCH3 expression and involvement in ossification pathways. Additionally, granulation tissue Fibroblast subpopulations demonstrated a progenitor-like state, characterized by extracellular matrix reorganization and low differentiation, similar to cancer-associated fibroblasts. Conclusion(s)This study advances the understanding of periodontal disease by characterizing key regulatory cell populations within granulation tissue. The identification of the novel endothelial subpopulation offers new insights into the diseases pathogenesis and presents potential targets for regenerative therapies. These findings suggest opportunities for developing biomaterials that modulate specific cellular pathways to improve periodontal disease treatment.