cell X1(FS) cell PMID:21566185 A heterogeneous sorted cell population of unstained planarian cells with similar size and complexity to irradiation-sensitive, cycling cells contained in the X1 gate. Unlike X1 cells, X1(FS) cells are amenable to cell transplantation. https://orcid.org/0000-0003-2569-1939 | https://orcid.org/0000-0002-7535-4407 Planarian_Anatomy FACS sorted cell population