We referred to the transcriptomic database obtained from renal tissue from subjects with DKD and controls (http://www.nephroseq.org) and found that the CD28 expression was higher in the kidneys of patients with DKD (fold change = 1.881, P = 0.011), but CD80 and CTLA4 expression showed no differences. This evidence concerns the gene CD28 and diabetic kidney disease.