In T2DM patients, CD4+CD28null T-cell frequency was positively correlated (r = 0.47; P < 0.001), and Treg frequency was negatively correlated (r = −0.41; P = 0.002) with disease duration (Figures 5(a) and 5(b)); moreover, CD4+CD28null T-cell frequency was positively correlated (r = 0.41; P = 0.008), and Treg frequency was negatively correlated (r = −0.52; P = 0.001) with HbA1c (Figures 6(a) and 6(b)); finally, a statistically significant correlation was found between hs-CRP levels and BMI (r = 0.47; P < 0.001) (Figure 7). This evidence concerns the gene CD4 and type 2 diabetes mellitus.