RESUMEN
Thrombus is a major factor leading to cardiovascular diseases such as myocardial infarction and stroke. Although fibrinolytic anti-thrombotic drugs have been widely used in clinical practice, they are still limited by narrow therapeutic windows, short half-lives, susceptibility to inactivation, and abnormal bleeding caused by non-targeting. Therefore, it is crucial to effectively deliver thrombolytic agents to the site of thrombus with minimal adverse effects. Based on the long blood circulation and excellent drug-loading properties of human serum albumin (HSA), we employed genetic engineering techniques to insert a functional peptide (P-selectin binding peptide, PBP) which can target the thrombus site to the N-terminus of HSA. The fusion protein was expressed using Pichia pastoris and purified by Ni-chelating affinity chromatography. After being loaded with gold nanoparticles (Au NPs), the fusion protein formed homogeneous and stable nanoparticles (named as PBP-HSA@Au) with a diameter of 17.7 ± 1.0 nm and a zeta potential of -11.3 ± 0.2 mV. Cytotoxicity and hemolysis tests demonstrated the superb biocompatibility of PBP-HSA@Au. Platelet-targeting experiments confirmed the thrombus-targeting ability conferred by the introduction of PBP into PBP-HSA@Au. Upon near-infrared ray (NIR) irradiation, PBP-HSA@Au rapidly converted light energy into heat, thereby disrupting fibrinogen and exhibiting outstanding thrombolytic efficacy. The designed HSA fusion protein delivery system provides a precise, rapid, and drug-free treatment strategy for thrombus therapy. This system is characterized by its simple design, high biocompatibility, and strong clinical applicability. All animal experiments involved in this study were carried out under the protocols approved by the Animal Experiment Ethics Committee of Jiangnan University [JN. No20230915S0301015(423)].