FOXP3 and B-cell chronic lymphocytic leukemia: Next, QDD and MP4 were tested on peripheral blood mononuclear cells (PBMCs) from chronic lymphocytic leukemia (CLL) patients, where FoxP3 downregulation in Tregs (normalized response) was accompanied by a stronger intrinsic activation of Teffs (higher CD69% in CD4 or CD8; Figure 5C).