CD4 and systemic lupus erythematosus: A statistically significant decrease was found in the percentage of Treg (CD4+CD25hiCD127−/low FOXP3+) cells from patients with SLE, both active and inactive, compared to that in healthy individuals, supporting the findings of previous studies.22,24,39,40 Additionally, the suppressor function exerted by Treg cells over Teff cells depends on the stage of the disease.