Here, we analyzed, in different T-cell subsets, how age and CMV infection alter the expression of the inhibitory receptors CD300a and CD161 and their relation with the marker CD57, which has been shown to be a polyfunctionality maker of CD4+, CD8+, and NKT-like T-cells (37, 38, 49). The gene discussed is CD4; the disease is cytomegalovirus infection.