Fig. 2: The differentially expressed gene pattern distinguishes 6 fibroblast cell clusters.

a TMJ disc tissues were dissected at different stages. Scale bar = 500 μm. N = 8 independent animals at each stage with similar results. b The diameter of each disc was measured under a stereoscopic microscope. Data are presented as mean values + /-SD. N = 8 independent animals at each stage. The one-way ANOVA with Tukey’s multiple comparison test was used, ^**p = 0.0097, ^****p < 0.0001. Scale bar: 500 μm. c UMAP of fibroblast clusters (FB1-FB6). Clusters were generated using a resolution of 0.2 prior to subclustering into major cell types according to the Methods. d Extracellular matrix markers of FBs. Blue: fibroblasts (FBs); yellow: macrophages (MPhs); green: endothelial cells (ECs); and red: mural cells (MCs). e Violin plot of the expression of selected differentially expressed genes (DEGs) of chondrogenesis related FB clusters in the four principal cell types. Expression values are nonnormalized. f Violin plot of the expression of selected DEGs of chondrogenesis related FB clusters in different FB clusters. Expression values are nonnormalized. g Violin plot of the expression of selected DEGs of non-chondrogenic FB cluster (proliferation). Expression values are nonnormalized. h Violin plot of the expression of selected DEGs of non-chondrogenic FB cluster (apoptosis). Expression values are nonnormalized. i Violin plot of the expression of selected DEGs of non-chondrogenic FB cluster (chondrogenesis inhibition). Expression values are nonnormalized. j Violin plot of the expression of Sfrp2. Expression values are nonnormalized.