Summary Systemic lupus erythematosus (SLE) is characterized by a deviation of the immune system that involves T cell-dependent autoantibody production. The aim of this study was to investigate the role of co-stimulatory markers on T cells in this disease. Twenty-eight patients with SLE as defined by the American College of Rheumatology (ACR) criteria and 11 healthy controls were included into the study. Eleven patients had biopsy-proven lupus nephritis while 17 patients had no clinical evidence of lupus nephritis. Clinical disease activity was assessed according to the systemic lupus erythematosus disease index (SLEDAI). CD4+ T cell populations in the peripheral blood were analysed for the expression of co-stimulatory markers CD45RO, CD70, CD80, CD86, CD137, CD137L, CD134, CD152, CD154 and ICOS. SLE patients showed an increased frequency of peripheral CD4+ T cells expressing high levels of CD80, CD86 and CD134 compared to healthy controls (7·1 ± 1·5%versus 1·7 ± 0·9%; P < 0·005; 2·3 ± 0·4%versus 1·0 ± 0·2%; P = 0·008, 20·2 ± 2·0%versus 10·6 ± 1·9%; P < 0·005, respectively). Significantly higher levels of CD80 on CD4+ T cells were detected in SLE patients with lupus nephritis compared to patients without nephritis (11·9 ± 3·3%versus 4·0 ± 0·7%; P < 0·005). There was an increased presence of CD134+ CD4+ cells in SLE patients with lupus nephritis (27·5 ± 4·0%versus 15·5 ± 1·3%; P < 0·005). CD80 and CD134 expression was significantly correlated with SLEDAI (r = 0·42, P = 0·03; r = 0·56, P < 0·005). Co-stimulatory molecules on CD4+ T cells are associated with renal disease and disease activity in patients with systemic lupus erythematosus.
Department of Nephrology, University Hospital Essen, Germany, 2:
Department of Hematology, University Hospital Essen, Germany, and 3:
Department of Rheumatology and Clinical Immunology, Kliniken Essen Süd, Germany