高效装载细胞内源蛋白工程化外泌体的构建

Construction of engineered exosomes with high loading efficiency of cellular endogenous proteins

摘要:

外泌体作为天然药物运送载体具有诸多优点，但其对细胞内源药物 (蛋白、核酸等) 的有限装载限制了其应用。文中以红色荧光蛋白mCherry为模拟细胞内源性货物，通过对供体细胞的基因改造及采用膜定位元件融合策略，将mCherry富集于细胞质膜，再经天然发生 (Biogenesis) 途径，高效分选进入外泌体。结果表明，在CAAX、PB、Palm和CD63四组膜定位元件中，CD63和Palm能有效提高靶蛋白mCherry在外泌体中的装载量。该研究可为工程化外泌体的设计、内源蛋白等货物的高效递送提供参考。

关键词:外泌体，药物运送载体，内源蛋白，膜定位元件，装载效率

Abstract:

Exosomes have many advantages as natural drug delivery carriers, but their application is limited by the inefficient loading of intracellular drugs (such as proteins and nucleic acids). In this study, mCherry, a red fluorescent protein, was used as the endogenous cargo target. Through gene modification of donor cells and fusion expression of membrane localization elements (PB, CAAX, Palm and CD63), mCherry was specifically sorted into exosomes through biogenesis. Results show that CD63 had the highest sorting efficiency, followed by Palm. PB and CAAX led enrichment of mCherry on the plasma membrane, but not in exosomes. The approach provides an alternative to facilitate packaging of cargo by exosomes and thus to increase the efficient delivery of endogenous protein drugs.

Key words:exosome, drug delivery carrier, endogenous protein, membrane localization element, loading efficiency