CTLA4 and B-cell chronic lymphocytic leukemia: Several studies have reported that T lymphocytes from patients with CLL are primed for anergy because of their higher expression of immune-checkpoint molecules, such as CTLA-4 [32], PD-1 [18,33], LAG3 [34], Tim-3 [35], TIGIT [36], CD160 and CD244 [37], leading to a microenvironment characterized by reduced T-cell proliferation, killing ability and cytokine release.