Targeting Modulated Vascular Smooth Muscle Cells in Atherosclerosis via FAP-Directed Immunotherapy [Human_CITEseq]

Vascular smooth muscle cell (VSMCs) cell diversification drives atherosclerotic coronary artery disease (CAD). Mechanisms governing these cell state transitions remain unclear. We applied multi-omic single-cell profiling, epitope mapping, and spatial transcriptomics across 27 human coronary arteries, identifying fibroblast activation protein (FAP) as a marker of modulated VSMCs. Lineage tracing in mice indicated that FAP⁺ cells originate from Myh11⁺ VSMCs, and FAP PET imaging in CAD patients showed plaque uptake. FAP⁺ cells states resided in the macrophage-rich neo-intima. Therapeutically, we developed an anti-FAP bispecific T-cell engager, which reduced plaque burden and remodeled the stromal–immune microenvironment through T-cell clonal expansion. Our study delivers a single-cell and spatial atlas of human CAD, establishes FAP as a marker of modulated VSMCs, and highlights immunotherapy for lipid-independent targets.