TY  - JOUR
AU  - Sato, Masahiro
AU  - Inada, Emi
AU  - Watanabe, Satoshi
AU  - Saitoh, Issei
AU  - Kubota, Naoko
AU  - Iwase, Yoko
AU  - Morohoshi, Kazunori
AU  - Nakamura, Shingo
PY  - 2025
DA  - 2025/11/24
TI  - Episomal Vectors: Principle, Utility, and Application
JO  - OBM Genetics
SP  - 317
VL  - 09
IS  - 04
AB  - An episomal vector is a plasmid- or virus-based vector that is present extrachromosomally in cells after transfection. Although it disappears during cell proliferation, it can exist in non-dividing cells, such as neuronal and muscular cells, and continues to express a gene of interest (GOI). Such episomal vectors are usually based on sequences from DNA viruses such as bovine papillomavirus 1 and Epstein-Barr virus. When cells are transfected with an episomal vector harboring a drug-resistance gene and subsequently cultivated in a medium containing a selective drug, the transfected cells would survive and continue to express the GOI. However, cultivating these cells in the absence of a drug may result in plasmid loss and reduced GOI expression. This seamless property of an episomal vector is especially advantageous for generating specific cells, as exemplified by induced pluripotent stem cells (which have been transdifferentiated after transfection of fibroblasts with reprogramming factors) without exogenous DNA. Moreover, the episomal vector has been improved using chromosomal S/MAR (scaffold/matrix attached region) derived from the β-interferon gene with episomal retention properties. This improved vector enables long-term expression of GOI, even in the absence of a selective drug. This property will be beneficial for its application in various scientific fields, including basic research (i.e., the generation of genetically modified animals) and gene therapy. This review describes the utility and applications of episomal vector-based gene expression systems.
SN  - 2577-5790
UR  - https://doi.org/10.21926/obm.genet.2504317
DO  - 10.21926/obm.genet.2504317
ID  - Sato2025
ER  -