Efficient Production of Mice from Embryonic Stem Cells Injected Into 4- or 8- Cell Embryos by Piezo Micromanipulation

¹ College of Life Sciences, Sun Yat-Sen University, Guangzhou 510275, China; Department of Obstetrics and Gynecology, University of South Florida College of Medicine, Tampa, FL. USA
² College of Life Sciences, Sun Yat-Sen University, Guangzhou 510275, China
³ College of Life Science, Nankai University, Tianjin 300071, China.
⁴ Department of Obstetrics and Gynecology, University of South Florida College of Medicine, Tampa, FL. USA
⁵ Department of Obstetrics and Gynecology, University of South Florida College of Medicine, Tampa, FL. USA; College of Life Science, Nankai University, Tianjin 300071, China.

^* To whom correspondence should be addressed. E-mail: liutelom{at}yahoo.com.

Correspondence may also be addressed to David L. Keefe at dkeefe@health.usf.edu

	Abstract

The conventional method for producing ES cell-derived knockout or transgenic mice involves injection of ES cells into normal, diploid embryos, followed by several rounds of breeding of resultant chimeras, and thus is a time consuming and inefficient procedure. F0 ES cell-pups can also directly be derived from tetraploid embryo complementation, which requires fusion of two-cell embryos. Recently, F0 ES cell-pups have been produced by injection of ES cells into 8-cell embryos using a laser-assisted micromanipulation system. We report a simple method for producing F0 ES cell- germline competent mice by Piezo injection of ES cells into 4- or 8-cell embryos. The efficiency of producing live, transgenic mice by this method is higher than the tetraploid blastocyst complementation method. This efficient and economical technique for directly producing F0 ES cell-offspring can be applicable in many laboratories for creating genetically manipulated mice using ES cell technology and also for stringent testing the developmental potency of new ES cell or other types of pluripotent stem cell lines.