婷婷六月丁香,午夜欧美日韩影视

您現(xiàn)在的位置：首頁 > 新聞動態(tài) > 行業(yè)新聞 >正文

細(xì)胞外囊泡核酸藥物開發(fā)面臨的挑戰(zhàn)

發(fā)表日期：2022-03-01

Challenges for the Development of Extracellular Vesicle-Based Nucleic Acid Medicines

細(xì)胞外囊泡核酸藥物開發(fā)面臨的挑戰(zhàn)

The development of nucleic acid drugs has progressed in recent years, especially in the field of cancer therapy, where there has been considerable progress in the development of siRNA-, antisense oligonucleotide-, and miRNA-related drugs. Extracellular vesicles are expected to play a pivotal role as a drug delivery system for nucleic acid drugs. By conjugating EVs with proteins, antibodies, or chemical antibodies called aptamers that specifically bind to cancer, EVs can be effectively delivered to tumor tissues and cells. This review summarizes the latest findings, serving as a bridge to the clinical application of nucleic acid drugs in cancer therapy.

近年來，核酸藥物的開發(fā)取得了長足的進步，特別是在癌癥治療領(lǐng)域，siRNA、反義寡核苷酸和miRNA相關(guān)藥物的開發(fā)取得了長足的進步。預(yù)計細(xì)胞外囊泡作為核酸藥物的給藥系統(tǒng)將發(fā)揮關(guān)鍵作用。通過將 EV 與蛋白質(zhì)、抗體或稱為適體的化學(xué)抗體結(jié)合，這些抗體可與癌癥特異性結(jié)合，EV 可以有效地遞送至腫瘤組織和細(xì)胞。本綜述總結(jié)了最新發(fā)現(xiàn)，為核酸藥物在癌癥治療中的臨床應(yīng)用提供了橋梁。

三角細(xì)胞搖瓶

Extracellular vesicles (EVs) are phospholipid bilayer membranous vesicles and are generated by almost all types of mammalian cells as a cell-to-cell communication tool [1]. EVs carry various nucleic acids, proteins, and lipids inherited from the cell of origin. EVs have been found in body fluids such as blood [2], urine [3], saliva [4], ascites [5], pleural effusion [6], cerebrospinal fluids [7], and amniotic fluids [8]. According to the International Society for Extracellular Vesicles (ISEV), EVs can be categorized into three main subtypes based on their size and biology: exosomes, microvesicles (MVs), and apoptotic bodies (ABs). Exosomes are approximately 100 nm in diameter and are the smallest type of EV. Exosome-specific surface markers, such as tetraspanins (CD9, CD81, CD63, flotillins), integrins, and heat shock proteins (HSP) 70 and HSP90, have been identified by Western blotting and enzyme-linked immunosorbent analysis [1,9,10]. Exosomes are formed in multiple steps. Early endosomes are formed through invagination of the plasma membrane [11]. The fusion of early endosomes results in the formation of late endosomes and multivesicular bodies (MVBs) during the maturation process, and intraluminal vesicles (ILVs) are formed by the invagination of the endosomal membrane into the lumen [12]. Some of the formed MVBs bind to lysosomes and are degraded, but other fusions with the plasma membrane release ILVs into the extracellular space as exosomes [13,14]. MVs are a few hundred nanometers to a few micrometers in diameter and are formed by direct outward budding from the plasma membrane [1,15]. Apoptotic bodies are several micrometers in diameter and are formed when cells undergo apoptosis. Various types of EVs have been reported, but they are not yet clearly distinguished. ISEV has recommended that particles with lipid bilayers that have been released from cells be referred to as EVs, but there are no specific markers yet to distinguish between EV subtypes [1].

細(xì)胞外囊泡 (EVs) 是磷脂雙層膜狀囊泡，幾乎所有類型的哺乳動物細(xì)胞都可以生成細(xì)胞外囊泡，作為細(xì)胞間通訊工具 [ 1 ]。EV 攜帶從起源細(xì)胞繼承的各種核酸、蛋白質(zhì)和脂質(zhì)。已在血液 [ 2 ]、尿液 [ 3 ]、唾液 [ 4 ]、腹水 [ 5 ]、胸腔積液 [ 6 ]、腦脊液 [ 7 ] 和羊水 [ 8 ]等體液中發(fā)現(xiàn) EV]。根據(jù)國際細(xì)胞外囊泡協(xié)會 (ISEV)，EV 可根據(jù)其大小和生物學(xué)特性分為三個主要亞型：外泌體、微泡 (MV) 和凋亡小體 (AB)。外泌體的直徑約為 100 nm，是最小的 EV 類型。外泌體特異性表面標(biāo)志物，例如四跨膜蛋白（CD9、CD81、CD63、flotillins）、整合素和熱休克蛋白 (HSP) 70 和 HSP90，已通過蛋白質(zhì)印跡和酶聯(lián)免疫吸附分析鑒定 [ 1 , 9 , 10 ]。外泌體在多個步驟中形成。早期內(nèi)體是通過質(zhì)膜內(nèi)陷形成的 [ 11]。早期內(nèi)體的融合導(dǎo)致在成熟過程中形成晚期內(nèi)體和多泡體 (MVB)，而腔內(nèi)囊泡 (ILV) 是由內(nèi)體膜內(nèi)陷到管腔中形成的 [ 12 ]。一些形成的 MVB 與溶酶體結(jié)合并被降解，但其他與質(zhì)膜的融合將 ILV 作為外泌體釋放到細(xì)胞外空間[ 13、14 ]。MV 的直徑為幾百納米到幾微米，是通過從質(zhì)膜直接向外出芽而形成的 [ 1 , 15]。凋亡小體直徑為幾微米，在細(xì)胞發(fā)生凋亡時形成。已經(jīng)報道了各種類型的電動汽車，但它們尚未明確區(qū)分。ISEV 建議將從細(xì)胞中釋放的具有脂質(zhì)雙層的顆粒稱為 EV，但目前還沒有特定的標(biāo)記來區(qū)分 EV 亞型 [ 1 ]。

細(xì)胞轉(zhuǎn)瓶

EVs have a lipid bilayer structure and express CD47, a membrane protein known as a “don’t eat me” signal. EVs are more biocompatible and less immunogenic than liposomes and accumulate more readily in cancer tissues than in normal tissues due to the fenestrated vascular structure of cancer tissue, known as the EPR effect. Although few studies have compared EVs with artificial nanovesicles, such as liposomes, the properties of EVs indicate that they could be useful drug delivery devices in cancer therapy. In addition, various modifications to EVs can increase their accumulation in tumors. For example, PEGylation reduces clearance by the MPS, and the addition of tumor-specific integrins or antibodies to the EV surface has been shown to increase tumor accumulation. Conjugating EVs with aptamers, also known as chemical antibodies, also increases the tumor accumulation potential of EVs. There are two methods of loading EVs. Pre-secretion loading involves the genetic modification of parental cells, while post-secretion loading involves the direct loading of nucleic acid drugs into EVs. Pre-secretion loading is a simple method, but its loading efficiency is unknown, and there are concerns about safety because it involves genetic modification. Electroporation is the most commonly used post-secretion loading method, but its loading efficiency needs to be carefully considered. Alternatively, Exo-fect is a commercially available kit that gives good loading efficiency and is a useful loading method. In general, considering the use of EVs as a drug delivery system for cancer treatment, there are various problems still to overcome, such as how to produce a large amount of EVs and how to collect them.

This review discusses the latest research on the combination of nucleic acid drugs and EVs. These EV-nucleic acid complexes might be future candidates for cancer therapy, and we hope that the technologies described herein will be used to develop novel nucleic acid drugs for anticancer therapy in the near future.

細(xì)胞培養(yǎng)瓶

EV 具有脂質(zhì)雙層結(jié)構(gòu)并表達(dá) CD47，這是一種被稱為“不要吃我”信號的膜蛋白。EV 比脂質(zhì)體更具生物相容性且免疫原性更低，并且由于癌組織的有孔血管結(jié)構(gòu)（稱為 EPR 效應(yīng)），EV 比在正常組織中更容易在癌組織中積累。盡管很少有研究將 EV 與人工納米囊泡（如脂質(zhì)體）進行比較，但 EV 的特性表明它們可能是癌癥治療中有用的藥物輸送裝置。此外，對 EV 的各種修改可以增加它們在腫瘤中的積累。例如，聚乙二醇化降低了 MPS 的清除率，并且已顯示向 EV 表面添加腫瘤特異性整合素或抗體會增加腫瘤積累。將 EV 與適體（也稱為化學(xué)抗體）結(jié)合，還增加了電動汽車的腫瘤積累潛力。有兩種加載 EV 的方法。分泌前加載涉及親代細(xì)胞的基因修飾，而分泌后加載涉及將核酸藥物直接加載到EV中。預(yù)分泌加載是一種簡單的方法，但其加載效率未知，并且由于涉及基因改造，因此存在安全性問題。電穿孔是最常用的分泌后上樣方法，但需要仔細(xì)考慮其上樣效率?；蛘撸?/span>Exo-fect 是一種市售試劑盒，可提供良好的加載效率，是一種有用的加載方法?？偟膩碚f，考慮到將電動汽車用作癌癥治療的藥物輸送系統(tǒng)，仍有各種問題需要克服，