Simple Derivation of Transgene-Free iPS Cells by a Dual Recombinase Approach

Induced pluripotent stem cells (iPSCs) can be derived from somatic cells by the introduction of the transcription factors Oct4, Sox2, Klf4 and cMyc using various methods. Here, we describe a new approach for the derivation of murine iPSCs using a polycistronic non-viral inducible vector integrated into pseudo attP sites via the C31 integrase-mediated site-specific recombination and subsequent vector excision by Cre recombinase. The pluripotency of the derived iPSCs was proved by in vitro and in vivo tests. The derived transgene-free iPSCs reactivated the endogenous pluripotency genes like e.g. Oct4, Sox2 and Nanog and the global gene expression profiles of iPSCs lines are highly similar to ESCs and distinct from parental murine fibroblasts. We demonstrated the differentiation potential of iPSCs by generation cells of the three germ layers as well as we successfully created germline chimeric mice from transgene-free iPSCs. In this study, we presented an efficient method for the generation of transgene-free iPSCs using dual-recombinase technology. expression data of iPSCs/ESCs/MEFs