CD4 and acute lymphoblastic leukemia: Furthermore, lymphatic tissues including the bone marrow, spleen and blood all show a large number of CD4 + /CD8 + progenitor T-cells (Fig. 4e, f), but not B-lymphocytes or myeloid cells (Supplementary Fig. 7d, e), indicating the presence of lymphoblastic T-cell leukemia (T-ALL).