Sorted T-ALL subsets engraft in NS122 xenografts. (A) Five primary T-ALL samples were sorted for CD34 and CD7 expression, then injected intrafemorally into NS122 recipients. Cell dose for each subset ranged from 3 × 10⁴ to 2.5 × 10⁶ cells with the cell dose determined previously by limiting dilution analysis. At least 2 recipients were injected for each T-ALL subset from each T-ALL sample. Engraftment was determined by flow cytometric analysis to detect human CD45⁺CD7⁺CD5⁺ cells in recipient RF. Each dot represents the percentage of human CD45⁺CD7⁺CD5⁺ cells from 1 recipient. The bar represents the mean percentage of CD45⁺CD7⁺CD5⁺ cells for each T-ALL sample. The CD34⁺CD7⁺ subset from 1 of 5 T-ALL samples engrafted in NS122 mice. (B) The CD34⁻CD7⁺ subset from 4 of 5 T-ALL samples engrafted in NS122 recipients. (C) T-ALL 0549 did not have any immunophenotype changes after engraftment in NS122 mice. Sorted CD34⁺CD7⁺CD1a⁻ cells from T-ALL 0549 engrafted in NS122 recipients with both CD34⁺CD7⁺CD1a⁻ and CD34⁻CD7⁺CD1a⁻ cells, reconstituting the original immunophenotype of the patient T-ALL.