1. Cell Engineering Laboratory, IdiPaz, La Paz Hospital Research Institute, Madrid Spain.
2. Department of Cell and Developmental Biology, Max Planck Institute for Molecular Biomedicine, Münster, Germany.
3. Centro de Investigación Cooperativa en Biociencias CIC bioGUNE, Parque Tecnológico de Bizkaia-Ed., Derio, Spain.
4. Biotechnology Program, CNIO, Madrid, Spain.
5. Sue and Bill Gross Stem Cell Research Center, University of California Irvine, Irvine, California.