Survival of bcCML mice in the absence of PD-1. (A) bcCML was induced in PD-1–deficient (—, n = 6) and naive C57BL/6 mice (, n = 6) by transferring retroviral transduced C57BL/6 bone marrow cells. Survival of recipient mice is shown in a Kaplan-Meier plot. One representative experiment of 3 is shown. (B) bcCML was induced by transferring 10⁵ (left) or 10⁴ (right, lower leukemia load) retroviral transduced C57BL/6 bone marrow cells into irradiated C57BL/6 mice. Survival of recipient mice is shown in a Kaplan-Meier plot for αPD-L1–treated mice (—, n = 6 [left], n = 5 [right]) and ratIgG-treated mice (, n = 6 [left], n = 3 [right]). (C) bcCML was induced with 10⁴ transduced bone marrow cells in irradiated recipient mice (lower leukemia load). Survival of bcCML mice treated with αCD8 (—, n = 5) or left untreated (, n = 7) is shown in a Kaplan-Meier plot. Statistical comparison was performed with the log-rank test.