Serial BM transplantation assay for HSCs within BM of Slug−/− or Slug+/+ mice. (A) A representation of flow cytometric analysis of donor test cell (CD45.2+)– and competitor cell (CD45.1+/CD45.2+)–derived BM cells in the secondary recipients (CD45.1+). (B) Enhanced repopulation capacity of Slug−/− BM MNCs during serial transplantation. BM MNCs from the recipient mice were serially transplanted into recipients as described in “Competitive BM transplantation coupled with serial transfer.” The repopulating capacity of Slug−/− and Slug+/+ BM donor cells was determined in primary (n = 7), secondary (n = 4), and tertiary (n = 3 or 4) recipients at 2 months after BM transplantation. Data shown are the mean ratio ± SD of donor test-derived cells to competitor-derived cells (*P < .05 and **P < .01 for Slug−/− vs Slug+/+).