Given our recent report showing the augmented immune responses related to Th1, Th2, and Th17 cells in CD4+Foxp3+ Treg-depleted atherosclerosis-prone mice (Kasahara et al., 2022), augmentation of these helper T cell responses may be caused by dysregulated CD4+Foxp3+ Treg responses in our Ccr4-/-Apoe-/- mice. Here, APOE is linked to atherosclerosis.