Generation of iTS cells via ES cells carrying an inducible Cdx2 transgene. (A) Southern blot analysis of ES clones carrying an inducible Cdx2 transgene, as detected by Cdx2-exon 1 probe. Four independent clones were tested. (B) Immunofluorescence analysis for Oct4, Nanog, and Cdx2. Tx, tamoxifen. (C) Quantitative RT-PCR analysis for Oc4, Nanog, and Cdx2 mRNA. Levels are normalized to β-actin levels, with ES level set to 1. Mean ± 1 SD is shown. n = 3 biological replicates. (D) iTS cells form TS-like colonies and giant cells (arrows) typically seen in the trophoblast lineage.