Fig. 1
From: Cytosolic phospholipase A2 as a therapeutic target for degenerative joint diseases
cPLA2 is predominatly expressed in preHTCs and up-regulated in OA cartilage. a Unbiased clustering of scRNA-seq data from human nonarthritic healthy (n = 3) and OA (n = 4) cartilage revealed 8 distinct cell clusters. b Stacked bar plot showing the proportion of chondrocyte subpopulations in human nonarthritic (n = 3) and OA (n = 4). c Density scatter plot of PLA2G4A expression visualized on the UMAP of chondrocyte. d Dot plot illustrating the expression patterns of PLA2G4A, MMP13 and ADAMTS5 across diverse chondrocyte subpopulations. e Representative immunofluorescence staining images of cPLA2 and Safranin O/Fast Green staining of human nonarthritic and OA cartilage. Scale bar = 100 μm. f Representative immunofluorescence staining images of cPLA2 and Safranin O/Fast Green staining of knee joints from ctrl, aged (18-month-old), and DMM mice (n = 6). Scale bar = 100 μm. g, h Density Scatter plot and density heatmap showing the distribution of OA-related (g) and SASP-related (h) gene sets across single-cell transcriptomic data. i Scatter plots depicting the relationships between PLA2G4A expression (x-axis) and the enrichment of OA-related genes (left) or SASP-related genes (right) across single cells. j, k Western blot analysis and quantification of cPLA2, p21, and γH2AX expression in primary human OA chondrocytes at passages 2 (P2) and 7 (P7) (n = 3). k, Data are mean±s.d., P-values by two-tailed unpaired Student’s t-test
