Abstract
Somatic cells can be reprogrammed into embryonic stem cells (ESCs) by nuclear transfer (NT-ESCs), or into induced pluripotent stem cells (iPSCs) by the "Yamanaka method." However, recent studies have indicated that mouse and human iPSCs are prone to epigenetic and transcriptional aberrations, and that NT-ESCs correspond more closely to ESCs derived from in vitro fertilized embryos than iPSCs. In addition, the procedure of NT-ESCs does not involve gene modification. Demonstration of generation of NT-ESCs using an easily-accessible source of adult cell types would be very important. Adipose tissue is a source of readily accessible donor cells and can be isolated from both males and females at different ages. Here we report that NT-ESCs can be generated from adipose tissue-derived cells (ADCs). At morphological, mRNA and protein levels, these NT-ESCs show classic ESC colonies, exhibit alkaline phosphatase (AP) activity, and display normal diploid karyotypes. Importantly, these cells express pluripotent markers including Oct4, Sox2, Nanog and SSEA-1. Furthermore, they can differentiate in vivo into various types of cells from 3 germinal layers by teratoma formation assays. This study demonstrates for the first time that ESCs can be generated from the adipose tissue by somatic cell nuclear transfer (SCNT) and suggests that ADCs can be a new donor-cell type for potential therapeutic cloning.