Nair Ashita, Bu Jiyoon, Rawding Piper A, Do Steven C, Li Hangpeng, Hong Seungpyo
Division of Pharmaceutical Sciences, School of Pharmacy, University of Wisconsin, Madison, WI 53705, USA.
Wisconsin Center for NanoBioSystems (WisCNano), School of Pharmacy, The University of Wisconsin-Madison, 777 Highland Ave., Madison, WI 53705, USA.
Nanomaterials (Basel). 2021 Dec 21;12(1):3. doi: 10.3390/nano12010003.
Extracellular vesicles (EVs) have been highlighted as novel drug carriers due to their unique structural properties and intrinsic features, including high stability, biocompatibility, and cell-targeting properties. Although many efforts have been made to harness these features to develop a clinically effective EV-based therapeutic system, the clinical translation of EV-based nano-drugs is hindered by their low yield and loading capacity. Herein, we present an engineering strategy that enables upscaled EV production with increased loading capacity through the secretion of EVs from cells via cytochalasin-B (CB) treatment and reduction of EV intravesicular contents through hypo-osmotic stimulation. CB (10 µg/mL) promotes cells to extrude EVs, producing ~three-fold more particles than through natural EV secretion. When CB is induced in hypotonic conditions (223 mOsm/kg), the produced EVs (hypo-CIMVs) exhibit ~68% less intravesicular protein, giving 3.4-fold enhanced drug loading capacity compared to naturally secreted EVs. By loading doxorubicin (DOX) into hypo-CIMVs, we found that hypo-CIMVs efficiently deliver their drug cargos to their target and induce up to ~1.5-fold more cell death than the free DOX. Thus, our EV engineering offers the potential for leveraging EVs as an effective drug delivery vehicle for cancer treatment.
细胞外囊泡（EVs）因其独特的结构特性和内在特征，包括高稳定性、生物相容性和细胞靶向性，而被视为新型药物载体。尽管人们已做出诸多努力，利用这些特性开发基于EVs的临床有效治疗系统，但基于EVs的纳米药物的临床转化却因产量低和载药量受限而受阻。在此，我们提出一种工程策略，通过细胞松弛素B（CB）处理使细胞分泌EVs来实现EVs的规模化生产并提高其载药量，同时通过低渗刺激减少EVs的囊泡内成分。CB（10 µg/mL）可促进细胞排出EVs，产生的颗粒数量比自然分泌的EVs多约三倍。当在低渗条件（223 mOsm/kg）下诱导CB时，产生的EVs（低渗诱导的多囊泡体，hypo-CIMVs）的囊泡内蛋白质减少约68%，与自然分泌的EVs相比，载药能力提高了3.4倍。通过将阿霉素（DOX）载入hypo-CIMVs，我们发现hypo-CIMVs能有效地将其药物载荷递送至靶标，诱导的细胞死亡比游离DOX多约1.5倍。因此，我们的EV工程为将EVs作为癌症治疗的有效药物递送载体提供了潜力。
