Histology of mice that received transplants. Immunohistologic analyses of different organs of a representative leukemic Cdx2 or W167A-Cdx2 mouse compared with a healthy animal from the ΔN-Cdx2 cohort. The spleen (Giemsa staining, ×640) of the analyzed Cdx2 and W167A-Cdx2 animals shows an infiltration with blast cells in contrast to the ΔN-Cdx2 animal that received a transplant. The liver of the Cdx2 and W167A-Cdx2 mice demonstrates perivascular infiltration with leukemic cells. Positivity for myeloperoxidase (MPO) and chloracetate esterase (CAE) confirmed the myeloid nature of the cells (×100 and ×400). May-Grunwald-Giemsa–stained cytospin preparations of cells isolated from the spleen (×640) or BM (×1000) of ΔN-Cdx2 mice that received transplants show mature lymphoid and myeloid cells, respectively. LN indicates lymph node; RP, red pulp; WP, white pulp; and CAE, chloracetate esterase.