Multilineage differentiation that favors myelopoiesis after an extended long-term engraftment. (A) The recipients were killed after tertiary cBMT and their BMNCs were collected and stained with lineage markers. Myeloid (Mac-1⁺), T (CD3⁺)–, and B (B220⁺)–cell lineages were sorted for semiquantitative PCR analysis as described in Figure 2C. The actual results are shown. Numbers above the gel images indicate individual animals, and the calculated percentages of donor cells are indicated below the PCR images. (B) Contribution of p18^-/- or p18^-/-p21^-/- donor cells to different lineages in tertiary recipients (6 months after transplantation). Error bars indicate SD. □ and ▪ indicate p18^-/- and p18^-/-p21^-/- transplantation groups, respectively. ^*P < .05 (n = 3, Student t test).