Macrophage-mediated CXCL2 regulation of EPC homing promotes the progression of atherosclerosis.

Atherosclerosis is a chronic inflammatory disease driven by pathological angiogenesis and plaque instability. Herein, we investigated the role of macrophage-derived CXCL2 in mediating endothelial progenitor cell (EPC) homing during atherosclerosis progression. Using ApoE-/- mice on a high-fat diet and in vitro co-culture models, we found that infused EPCs exacerbated plaque burden, neovascularization, and matrix degradation. Macrophages were essential for EPC recruitment to plaques. Ox-LDL-stimulated macrophages enhanced EPC angiogenic functions, with transcriptome sequencing identifying CXCL2 as a key upregulated mediator. Functional experiments confirmed CXCL2's critical role. In vivo silencing of CXCL2 attenuated EPC homing, reduced plaque size and lipid accumulation, decreased neovascularization, and stabilized the plaque matrix. Our findings demonstrate that macrophages promote pathological angiogenesis and plaque progression via CXCL2, suggesting that targeting this chemokine could be a novel therapeutic strategy for stabilizing atherosclerotic plaques.