Among the studies, five used “CD25low/−FOXP3+” to define Tregs, and three simply “FOXP3+”; the proportion of Tregs in SLE patients appeared to be higher than in controls [5.409, (2.112, 8.705), p = 0.001; 1.101, (0.435, 1.768), p = 0.001, resp.]. Here, FOXP3 is linked to systemic lupus erythematosus.