Abstract 6587: Plasma-derived exosomes in the frontier of gene therapy development

Abstract Gene transfer refers to the process of incorporating foreign genetic material, such as DNA or RNA, into target cells or organisms. Gene transfer is a dynamic field with significant potential for advancing medicine, biotechnology, and scientific research. Ongoing research and technological developments aim to enhance the efficiency, safety, and precision of gene transfer techniques for various applications. In the transportation of genetic materials such as DNA, miRNA, mRNA, and siRNA, various challenges are encountered, and these challenges are being addressed through the approach of nanobiotechnology. Exosomes are promising natural carriers for gene delivery systems. Due to their high biocompatibility, stability, and low immunogenicity, exosomes are preferred as cargo carriers. The lipid bilayer membrane of exosomes also provides protection against cargo degradation, making exosomes a desirable candidate for gene delivery. Despite the various strategies developed to facilitate the loading of the desired cargo, such as incubation, electroporation, sonication, extrusion, freeze-thaw cycles, and transfection, insufficient efficiency persists. Our main goal is to develop a highly efficient gene transfer method for exosomes isolated from healthy human blood plasma. In our study, the gene transfer capacities of exosomes isolated from human blood plasma were examined. First, an exosome isolation method from plasma was developed. The most efficient method for exosome isolation has been developed, and for this purpose, both the ultracentrifugation method without gradients and the sucrose gradient have been studied. Based on exosome characterizations with NTA and Western blot, it was determined that the best method was the 30% sucrose gradient. Then, the gene delivery capacity of exosomes as a cargo molecule was examined using FAM-labeled GAPDH-siRNA. In our study, the sonication and the extrusion methods were compared for the loading of genes into exosomes. When evaluating all parametric comparisons, the highest efficiency of gene loading capacity into exosomes was achieved using the sonication method. The gene loading efficiency of exosomes was also determined using FAM-labeled GAPDH-siRNA through fluorescence microscopy and flow cytometry. The cellular uptake of GAPDH-siRNA-loaded exosomes was evaluated based on time and concentration. Cellular uptake within 6-12-24 hours was evaluated. When all these results are evaluated, our study has developed a gene therapy agent to be used for gene therapy purposes, which will guide us in our future gene therapy studies against cancer. In this way, fundamental cases will be provided for more efficient and effective gene therapy through exosomes, which is one of today's most important and favored treatments. Research has been supported by the Erciyes University Scientific Research Projects (BAP) Grant No: TSAÜ-2024-13269. Citation Format: Gizem Kursunluoglu, Omer Aydin, Mükerrem Betül Yerer. Plasma-derived exosomes in the frontier of gene therapy development [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2025; Part 1 (Regular Abstracts); 2025 Apr 25-30; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2025;85(8_Suppl_1):Abstract nr 6587.