Functional marker expression associated with exhaustion is higher in nonresponders in both the periphery and the BM microenvironments. (A) Staining of representative populations of interest (peripheral CD8, CD4, and CD3 T cells). (B) Frequency of PD-1⁺/CD8 T cells, CD38⁺/CD4 T cells, and PD-1⁺TIM-3⁺/CD3 T cells in the periphery at baseline in patients treated with the RP2D assessed by flow cytometry. (C) Frequency of PD-1⁺/CD8 T cells, CD38⁺/CD4 T cells, and PD-1⁺TIM-3⁺/CD3 T cells in the BM at baseline in patients treated with the RP2D assessed by flow cytometry. Groups were compared using the Wilcoxon rank-sum test.