The transcription factor NF-Y promotes myeloid cell survival and protects from inflammatory vascular disease.

Myeloid cells orchestrate vascular inflammation through transcriptional programs that control their maturation, effector function, and survival. While lineage-determining transcription factors establish myeloid identity, our understanding of the transcriptional regulation of myeloid cell behavior in chronic inflammatory contexts remains limited. Nuclear factor-Y (NF-Y) is a trimeric CCAAT-binding transcription factor that regulates cell proliferation and differentiation and is essential for maintaining stem and progenitor cell fitness. Here, we investigate NF-Y activity in myeloid cell function and survival using integrated single-cell transcriptomics and myeloid-specific deletion of the NF-YA subunit. At RNA level, NF-Y subunit transcripts were detected across myeloid compartments, with NF-YA enriched in proliferative macrophages and immature neutrophils. In mouse atherosclerotic lesions, low NF-YA levels were associated with macrophages exhibiting lipid-handling and phagocytic signatures and with neutrophils displaying a proinflammatory phenotype. NF-Y deficiency impaired neutrophil adhesion and rolling, increased their susceptibility to apoptosis, and promoted activation and lipid accumulation in macrophages. In vivo, myeloid NF-YA deficiency reduced circulating neutrophil counts, increased macrophage and neutrophil apoptosis during acute inflammation, expanded necrotic cores, leading to larger and more unstable atherosclerotic lesions, and aggravated both atherosclerosis and injury-induced neointimal thickening. These findings identify NF-Y as a transcriptional safeguard of myeloid cell survival during inflammatory stress, thereby shaping disease progression and outcomes in vascular disease.