CTLA4 and systemic lupus erythematosus: Figure 4A to E showed SLE patients with nephritis exhibited higher frequencies of CD4+ T cells expressing PD1, CTLA4, TIM3, CD127 and TIGIT [CD4 + CD279 + (6.162 ± 0.6218%, (N = 65) vs. 10.57 ± 1.938%, (N = 23), p = 0.0056); CD4 + CTLA4 + (0.1545 ± 0.04463%, (N = 66) vs. 0.5565 ± 0.1915%, (N = 23), p = 0.0038); CD4 + TIM3 + (3.279 ± 0.4234%, (N = 66) vs. 7.378 ± 1.095%, (N = 23), p < 0.0001); CD4 + CD127 + (28.55 ± 2.72%, (N = 67) vs. 49.3 ± 2.767%, (N = 23), p < 0.0001); CD4 + TIGIT + (24.13 ± 1.297%, (N = 67) vs. 30.14 ± 1.978%, (N = 23), p = 0.0184)].