叶酸修饰的NK细胞外泌体递送呼肠孤病毒抗卵巢癌的作用及机制OA

Objective:To develop a novel delivery system for oncolytic reovirus(Reo)to circumvent neutralization by anti-Reo antibodies and enhance tumor-targeting efficiency.Methods:Natural killer cell-derived exosomes(NKexo)were prepared via tangential flow filtration combined with ultracentrifugation.After folic acid(FA)modification,Reo was encapsulated into NKexo using an extrusion method to construct the FA-NKexo-Reo delivery system.The physicochemical properties of FA-NKexo-Reo were characterized by transmission electron microscopy(TEM),nanoparticle tracking analysis,Western blot,proton nuclear magnetic resonance spectroscopy,and flow cytometry.The in vitro cytotoxicity and cellular uptake of FA-NKexo-Reo was evaluated using CCK-8 assays,flow cytometry,Transwell assays,and confocal laser microscopy.A human ovarian cancer xenograft model in nude mice was established to assess the tumor-targeting capability,therapeutic efficacy,and treatment safety of FA-NKexo-Reo.Results:FA-NKexo-Reo exhibited an average particle size of(94.0±28.5)nm and a zeta potential of(-21.26±1.57)mV,with an encapsulation efficiency of(49.7±15.6)％.In the presence of neutralizing antibodies,FA-NKexo-Reo retained significant cytotoxicity against SKOV3 and A2780 ovarian cancer cells(P＜0.01).In vivo fluorescence imaging demonstrated superior tumor-targeting capability of FA-NKexo-Reo compared to NKexo,with a 60％increase in tumor suppression rate(P＜0.001).Conclusion:The FA-NKexo-Reo delivery system was successfully prepared.In the presence of neutralizing antibodies,FA-NKexo-Reo effectively protects and selectively delivers Reo to ovarian cancer cells with high folate receptor expression,significantly enhancing the antitumor efficacy of Reo.