Published online Aug 26, 2015. doi: 10.4252/wjsc.v7.i7.1054
Peer-review started: August 23, 2014
First decision: September 28, 2014
Revised: May 29, 2015
Accepted: July 16, 2015
Article in press: July 18, 2015
Published online: August 26, 2015
Embryonic stem (ES) cells are isolated from the inner cell mass of a blastocyst, and are used for the generation of gene-modified animals. In mice, the transplantation of gene-modified ES cells into recipient blastocysts leads to the creation of gene-targeted mice such as knock-in and knock-out mice; these gene-targeted mice contribute greatly to scientific development. Although the rat is considered a useful laboratory animal alongside the mouse, fewer gene-modified rats have been produced due to the lack of robust establishment methods for rat ES cells. A new method for establishing rat ES cells using signaling inhibitors was reported in 2008. By considering the characteristics of rat ES cells, recent research has made progress in improving conditions for the stable culture of rat ES cells in order to generate gene-modified rats efficiently. In this review, we summarize several advanced methods to maintain rat ES cells and generate gene-targeted rats.
Core tip: Rat embryonic stem (ES) cells are thought to be an essential tool for creating transgenic rats. Since the method for establishing rat ES cells using signaling inhibitors was reported, numerous approaches have been made to propagate rat ES cells efficiently. Additionally, recent investigations have demonstrated the usefulness of the signal inhibitors for microinjection. In this review, we summarize the several advanced methods to maintain rat ES cells and generate gene-targeted rats.