Department of Medical Biotechnology, Faculty of Medical Science, Tarbiat Modares University, P.O.Box:14115-331 I.R, Jalal ale Ahmad Highway, Tehran, Iran.
Immunogenetic Research Center, Mazandaran University of Medical Sciences, Sari, Iran.
Appl Biochem Biotechnol. 2019 Jan;187(1):352-364. doi: 10.1007/s12010-018-2813-4. Epub 2018 Jun 28.
Exosomes are the best options for gene targeting, because of their natural, nontoxic, non-immunogenic, biodegradable, and targetable properties. By engineering exosome-producing cells, ligands can be expressed fusing with exosomal surface proteins for targeting cancer cell receptors. In the present study, HER2-positive breast cancer cells were targeted with a modified exosome producing engineered HEK293T cell. For this purpose, the HEK293T cells were transduced by a lentiviral vector bearing-LAMP2b-DARPin G3 chimeric gene. Stable cells expressing the fusion protein were selected, and the exosomes produced by these cells were isolated from the culture medium, characterized, and then loaded with siRNA for subsequent delivery to the SKBR3 cells. Our results showed that stable HEK293T cells produced DARPin G3 on the surface of exosomes. These exosomes can bind specifically to HER2/Neu and are capable of delivering siRNA molecules against TPD52 gene into SKBR3 cell line down-regulating the gene expression up to 70%. Present approach is envisaged to facilitate genes and drugs transfer to HER2 cancer cells providing additional option for gene therapy and drug delivery.
外泌体是基因靶向的最佳选择，因为它们具有天然、无毒、非免疫原性、可生物降解和可靶向的特性。通过工程化产生外泌体的细胞，可以将配体与外泌体表面蛋白融合表达，从而靶向癌细胞受体。在本研究中，使用经过修饰的产生外泌体的工程化 HEK293T 细胞来靶向 HER2 阳性乳腺癌细胞。为此，通过携带 LAMP2b-DARPin G3 嵌合基因的慢病毒载体转导 HEK293T 细胞。选择表达融合蛋白的稳定细胞，并从培养基中分离这些细胞产生的外泌体，对其进行表征，然后负载 siRNA 以随后递送至 SKBR3 细胞。我们的结果表明，稳定的 HEK293T 细胞在其外泌体表面表达 DARPin G3。这些外泌体可以特异性地与 HER2/Neu 结合，并能够将针对 TPD52 基因的 siRNA 分子递送至 SKBR3 细胞系，使基因表达下调高达 70%。目前的方法预计将促进基因和药物向 HER2 癌细胞的转移，为基因治疗和药物递送提供了额外的选择。
