title: Reply to Chi et al.
authors.affiliation: University College London Institute of Child Health, London, UK.
authors.forename: Grace
authors.initials: G
authors.lastname: Kaushal
authors.affiliation: Centre for Stem Cells and Regenerative Medicine at King's College London, London, UK.
authors.forename: Emanuel
authors.initials: E
authors.lastname: Rognoni
authors.affiliation: Department of Dermatology, Medical University of Vienna, Skin and Endothelium Research Division, Vienna, Austria.
authors.forename: Beate M
authors.initials: BM
authors.lastname: Lichtenberger
authors.affiliation: Centre for Stem Cells and Regenerative Medicine at King's College London, London, UK.
authors.forename: Ryan R
authors.initials: RR
authors.lastname: Driskell
authors.affiliation: Hubrecht Institute-Royal Netherlands Academy of Arts and Sciences (KNAW) and University Medical Centre (UMC) Utrecht, The Netherlands.
authors.forename: Kai
authors.initials: K
authors.lastname: Kretzschmar
authors.affiliation: Unit for Cellular and Molecular (Patho)physiology, Inflammation Research Center, VIB, Ghent, Belgium and Department of Biomedical Molecular Biology, Ghent University, Ghent, Belgium.
authors.forename: Esther
authors.initials: E
authors.lastname: Hoste
authors.affiliation: Centre for Stem Cells and Regenerative Medicine at King's College London, London, UK. Electronic address: fiona.watt@kcl.ac.uk.
authors.forename: Fiona M
authors.initials: FM
authors.lastname: Watt