Although the size of the population of CD4 + CD45RO + CD57+ cells showed no relationship with insulin resistance status in the participants with T2D (Fig. 2c), the number of CD8 + CD45RO + CD57+ cells was much higher in patients with high HOMA-IR (Fig. 2d and Supplementary Table 2). Here, CD4 is linked to type 2 diabetes mellitus.