Engraftment of CD34⁺CLL-1⁺ AML blasts in NOD/SCID mice. FACS-sorted CD34⁺CLL-1⁺ cells from 3 different AML patients were transplanted into NOD/SCID mice. Six weeks after transplantation, the mice were killed and engraftment of human cells in these mice was studied using human anti-CD45. In this figure, the overall results are depicted on a logarithmic scale; every symbol represents the percentage engraftment of human CD45⁺ cells in one mouse. In a mouse that received a transplant of the whole CD34⁺ population from patient 2, which included the CD34⁺CD38⁻CLL⁺, but also a clear CD34⁺CD38⁻CLL-1⁻ population (15% of the CD34⁺CD38⁻ population), outgrowth of CD45^dimCD33⁺CD19⁻ AML cells was likewise accompanied by outgrowth of CD45^dimCD33⁻CD19⁺ cells (18% of human cells), which are presumably normal (data not shown).²²  Horizontal lines represent the mean percentage engraftment of leukemic cells.