Macrophage-Derived TNF-α Promotes Vascular Inflammation and Cell Crosstalk in Human Atherosclerotic Plaques via TNFRSF1A

Aims Atherosclerosis (AS) is a chronic inflammatory disease driven by complex cellular crosstalk within plaques. How a key inflammatory pathway orchestrates multicellular vascular injury and whether this is conserved across vascular beds remains incompletely understood. Methods Carotid and coronary plaques were profiled by single-cell RNA sequencing and spatial transcriptomics. Immunofluorescence validated cell localization and TNF–TNFRSF1A signaling, and CellChat analyzed intercellular communication. THP-1 macrophages were subjected to hypoxia/nutrient deprivation or ox-LDL, and conditioned media were applied to endothelial and smooth muscle cells to assess TNFRSF1A-dependent cytotoxicity, NF-κB/MAPK activation, lipid accumulation, and cytokine release. Results Single-cell and spatial analyses revealed a conserved plaque architecture: myeloid cells enriched in the lipid core, mural and endothelial cells at the periphery. Five endothelial, eight mural, and six macrophage subtypes showed distinct spatial and functional features. Central to these interactions, TNF–TNFRSF1A emerged as a central signaling axis linking macrophages, endothelial cells, and smooth muscle cells. Microenvironmental stress amplified macrophage TNF-α secretion, leading to promoting TNFRSF1A-dependent vascular cell death, NF-κB/MAPK activation, and foam cell formation. Mechanistically, ox-LDL upregulated increased macrophage CD36 and TREM2, while TNFRSF1A knockdown mitigated lipid accumulation, cytokine release, and downstream signaling. Conclusions These findings delineate the spatial and functional landscape of AS plaques and reveal a conserved, spatially constrained mechanism: macrophage-derived TNF-α drives TNFRSF1A-dependent vascular injury, inflammatory amplification, and foam cell formation, highlighting this axis as a promising therapeutic target for atherosclerotic diseases.