Fig. 6: SRGN secreted by late-stage NPCs increases macrophage infiltration.

a, b UMAP plot of the following 3 clusters of macrophages: cluster 0 (TNF⁺), cluster 1 (VENTX⁺), and cluster 2 (MARCO⁺). c The propositions of 3 clusters in MDD and SDD IVDs. d UMAP plot of cluster 0 (TNF⁺) macrophages and M1 macrophages. e QuSAGE gene set analysis heatmap showing that cytokine and proinflammatory gene sets are significantly expressed. f Seurat4RDSPlot analysis shows that CCL3, IL1B, and TNF are significantly increased in cluster 0 macrophages. g QuSAGE pathways analysis showed that the proinflammatory gene set and NF-κB signaling pathway gene set were significant in cluster 0 macrophages. h CellPhone and receptor analysis of TNF⁺ macrophages showed that TNF⁺ macrophages are regulated by Fibro-NPCs with CCL3, IL-1β, and TNF-α receptors. i–l Migration of macrophage RAW264.7 cells after SRGN, si-SRGN or si-P65 treatment (original magnification ×100, scale bar = 200 µm). n = 3 each group. (m) Flow cytometry of CD11c+ and CD86 + RAW264.7 cells treated with SRGN and si-P65. n, o IF staining of F4/80 (green) and CD86 (red) and quantitative analysis in WT, Srgn^−/−, WT plus AF, and Srgn^−/− plus AF mice (original magnification ×100, ×400, scale bar = 400 µm, 100 µm). n = 3 each group in (i–m), n = 5 each group in (n) and (o). Data are represented as the mean ± standard deviation. p values were determined by one-way ANOVA with a post hoc Bonferroni correction or a Kruskal‒Wallis H test with Dunn’s correction. Source data are provided as a Source Data file.