In the present study, an expected difference was observed between different cell sorting analysis strategies (p = 0.022): Tregs gated based only on CD25 staining (CD4+CD25+/high) (25–29, 31, 42–44) showed lower percentages of Tregs in active SLE than those in controls (−1.672 ± 0.472, p < 0.001), whereas normal frequencies were observed when FoxP3+ or CD127low/Ø was chosen to define Tregs (−0.269 ± 0.404, p = 0.505) (30–39, 42–44). The gene discussed is CD4; the disease is systemic lupus erythematosus.