Decrease of regulatory T cells in patients with systemic lupus erythematosus

Current evidence indicates that regulatory T cells (Tregs) actively suppress autoreactive lymphocytes that escape central tolerance.1,2 Tregs are characterised by a high intensity CD25 constitutive expression3 on the surface of CD4 T lymphocytes, which distinguishes them from the non-regulatory CD4+CD25+ T lymphocytes.4 Because of their important role in the maintenance of tolerance, it has been suggested that Tregs are decreased in patients with systemic lupus erythematosus (SLE).5 We have quantified Tregs in patients with SLE and controls and evaluated their association with disease activity and treatment. Thirty three patients with SLE (26 women, 7 men) and 14 healthy volunteers matched for age and sex (11 women, 3 men) with a mean age of 39.9 and 36 years, respectively, were studied. All patients fulfilled at least four of the American College of Rheumatology 1982 revised criteria for the classification of SLE.6 Disease activity at the time of blood sampling was assessed using the SLE Disease Activity Index (SLEDAI).7 …