Engineering a single-chain vascular endothelial growth factor with enhanced physiological stability for accelerating...

Vascular endothelial growth factor (VEGF) is characterized by its homodimeric structure, in which two cysteine-knot subunits are covalently linked. Although its profound pro-angiogenic activity presents considerable therapeutic promise, challenges associated with dimer stability and its short physiological half-life restrict its clinical translation. To address these limitations, we engineered prototype VEGF-A165 into a single-chain construct, V165-CTP-V165, by incorporating the C-terminal peptide (CTP) of human chorionic gonadotropin as a linker to enhance dimerization efficiency and improve protein stability of VEGF. Recombinant V165-CTP-V165 protein exhibited comparable bioactivities to native human VEGF-A165 (rhVEGF) in promoting endothelial cell proliferation, migration, and tube formation in vitro, and neovascularization in vivo. Notably, CTP modification significantly extended the VEGF's half-life in circulating blood by up to 4.5-fold and in wound exudates by up to 6-fold. When applied to a murine excisional wound model, a single topical administration of V165-CTP-V165 was sufficient to accelerate wound closure compared to rhVEGF as evidenced by enhanced neovascularization, re-epithelialization and dermal reconstitution. These findings highlight the potential of V165-CTP-V165 as an improved VEGF-based therapeutic biomaterial with enhanced stability and physiological efficacy for diverse applications, including wound care and tissue regeneration.