Minning S, Xiaofan Y, Bingjie G, et al. - Cell isolation and flow cytometry analysis were used to examine the T-cell subsets by the researchers in order to assess the alterations in CD8⁺CD28^–/CD8⁺CD28⁺ T-cell subset balance and in the CD8⁺CD28^– Treg cell number and function in individuals with systemic lupus erythematosus (SLE). It was observed that in high-activity SLE individuals, the CD8⁺CD28⁺ T-cell subset was decreased, which was inversely related to the Systemic Lupus Erythematosus Disease Activity Index (SLEDAI), and that the CD8⁺CD28^-/CD8⁺CD28⁺ ratio was raised, which was positively associated with SLEDAI and with renal damage and inversely related to serum complement level, whereas the CD8⁺CD28^- T-cell subset was progressed only in inactive individuals. Apoptosis of CD8+ T cells multiplied, and Fas, Fas ligand (FasL) and interleukin (IL)-6 expression were high, whereas cytotoxic T-lymphocyte–associated antigen 4 (CTLA-4) expression was low by the CD8⁺CD28⁺ T cell subset in the active SLE individuals and apoptosis was positively associated with SLEDAI and with the expression of Fas and FasL by the CD8⁺CD28⁺ T-cell subset in active SLE individuals. In active SLE individuals, IL-6 and CTLA-4 expression were noted to be low by the CD8⁺CD28^- T cell subset. In conclusion, in active SLE individuals, high expression of Fas, FasL and IL-6 and low expression of CTLA-4 by the CD8⁺CD28⁺ T-cell subset promoted the activation-induced cell death of the CD8⁺CD28⁺ T-cell subset, leading to an imbalance of CD8⁺CD28^-/CD8⁺CD28⁺ T cells, which exhibited a significant chahracteristic in the immunological pathogenesis of SLE. The CD8⁺CD28^- T-cell subset could play some part in inactive SLE.