MFAP4 (microfibrillar associated protein 4) is a 36-kDa extracellular matrix glycoprotein that plays critical roles in elastic fiber assembly and maintenance 1. The protein forms calcium-dependent octamers through homodimer assembly, which are essential for its interactions with elastogenic proteins including fibrillin-1 and tropoelastin 1. MFAP4 functions as an integrin αvβ3/5/6 ligand, mediating cell adhesion and intercellular interactions 23. The protein is highly expressed in elastic fiber-rich tissues, particularly in blood vessels, heart, lung, and intestine 45. MFAP4 has significant disease relevance, being upregulated in liver fibrosis where it promotes hepatic stellate cell activation through FAK/PI3K/NFκB signaling 3, and is associated with cardiovascular diseases and chr17 kidney disease progression 46. Clinically, MFAP4 shows promise as both a biomarker and therapeutic target, with serum levels varying in cardiovascular conditions 4 and anti-MFAP4 antibodies demonstrating efficacy in reducing retinal neovascularization and vascular leakage 2. The protein's expression is regulated by retinol and coenzyme Q10 through a TATA-less promoter 5.