Our study also confirmed that both the percentages of ICOS (5.24 ± 5.04%, n = 10 versus 1.36 ± 0.64%, n = 9, P < 0.05) and PD-1 (18.3 ± 8.13%, n = 10 versus 8.71 ± 4.65%, n = 10, P < 0.05) on CD4+ T cells were higher in SLE patients than in HCs (Fig. 6C, D). The gene discussed is CD4; the disease is systemic lupus erythematosus.