Conclusions
Our results provided deep insights into the immune ecosystem and highlighted the potential chemotactic effects of chemokine-enriched myofibroblasts within OKCs. The close interaction between immune cells and fibroblasts demonstrated in this study may be responsible for the osteoclastogenic effects of OKC fibroblasts.
Methods
Mass cytometry of 41 markers was employed for the classification of OKC cells from six OKC samples. Immunofluorescence staining and single-cell RNA sequencing (GSE176351) were used for the detection of fibroblast subpopulations. Enzyme-linked immunosorbent assay and immunofluorescence staining were employed for chemokine detection in hypoxia- and/or HIF-1α inhibitor-treated OKC fibroblasts and tissues. Chemotaxis assay was employed to determine the chemotactic effect of fibroblasts via co-culture with peripheral blood mononuclear cells. A cell communication network was constructed based on the single-cell RNA sequencing data.
Results
The characterization of the immune cell types of OKC evidenced the enrichment of macrophages, neutrophils and B cells. The majority (41.5%) of fibroblast subsets consisted of chemokine ligand-enriched myofibroblasts. The activation of the HIF-1α signaling pathway in fibroblasts was associated with chemokine release. The chemokines released by OKC fibroblasts remarkably promoted the migration of peripheral blood mononuclear cells in the co-culture system. Close interactions between myofibroblasts and immune cells were validated by cell-cell interaction analysis. Increased RANKL expression was detected in OKC fibroblasts in the co-culture system with peripheral blood mononuclear cells. Conclusions: Our results provided deep insights into the immune ecosystem and highlighted the potential chemotactic effects of chemokine-enriched myofibroblasts within OKCs. The close interaction between immune cells and fibroblasts demonstrated in this study may be responsible for the osteoclastogenic effects of OKC fibroblasts.