CD4 and acute lymphoblastic leukemia: In addition, the majority of PtenΔ/Δ and PtenΔ/Δ;p110αΔ/Δ-recipient mice developed T-ALL as evidenced by the abundance of donor-derived CD45.2+ CD3+;CD4+ or CD3+CD4− T lymphoblasts at the experimental end point of 20 weeks in these mice (Fig. 4b; Supplementary Fig. 6).