PPBP (pro-platelet basic protein) encodes a multifunctional inflammatory mediator primarily released from activated platelets that plays critical roles in immune responses and vascular pathology. The protein functions as a chemokine that activates neutrophils through CXCR1 and CXCR2 receptors, promoting neutrophil chemotaxis and activation 1. PPBP demonstrates significant upregulation in cardiovascular diseases, serving as a potential biomarker for coronary heart disease risk in both men and postmenopausal women with hyperlipidemia 23. Mechanistically, PPBP exacerbates atherosclerosis by inducing mitochondrial dysfunction in aortic endothelial cells through suppression of zinc homeostasis regulator ZNG1F, leading to oxidative stress 4. The protein also facilitates CD8+ T cell migration to intestines via PPBP-CXCR2 interactions, contributing to stress-related depression through modulation of gut microbiome metabolism 5. Additionally, PPBP expression is elevated in various inflammatory conditions including severe acute pancreatitis, where it marks specific monocyte subpopulations 6, and interstitial lung abnormalities with fibrotic patterns 7. These findings establish PPBP as a key inflammatory mediator linking platelet activation to systemic inflammatory responses and cardiovascular pathology.