CD274 and acute myeloid leukemia: For patients, the percentage of PD‐L1 expression on Bregs was significantly different before and after chemotherapy (BM and PB, AML‐T0 vs. AML‐T1, both p < 0.001; PB, AML‐T0 vs AML‐T2, p = 0.017), as shown in Figure 2.