FOXP3 and systemic lupus erythematosus: We observed a significant increase in proportions of CD4+CD25-Foxp3+ T cells in patients with renal involvement (6.7 ± 1.1%) as compared to patients with no renal involvement (3.6 ± 0.4%; P = 0.005) and in patients with active nephritis (7.9 ± 1.6%) as compared to SLE patients with no active nephritis (4.3 ± 0.5%; P = 0.005).