AB0139 Interleukin-21 Is Overexpressed in Kidney Tissue from Lupus Nephritis Patients and Its Serum Levels Are Correlated with Systemic Lupus Erythematosus Disease Activity. (15th July 2016)

• Record Type: Journal Article
• Authors: Kim, J.-M.; Jeong, H.-J.; Kim, S.-H.; Park, S.-H.
• Is Part Of: Annals of the rheumatic diseases. Volume 75(2016)Supplement 2
• Page Start: 944
• Page End: 944
• Publication Date: 2016-07-15
• Subjects: Rheumatism -- Periodicals; 616.723005
• DOI: 10.1136/annrheumdis-2016-eular.4506
• Languages: English
• ISSNs: 0003-4967

Abstract

Abstract : Background: Interleukin-21 (IL-21) has various effects on a number of immune cells including B cells, T cells, natural killer (NK) and NKT cells. One of the essential roles of IL-21 is to contribute to autoantibody production as a result of promoting hyperactivity of B cells. Systemic lupus erythematosus (SLE) is a prototypic autoimmune disease characterized by pathogenic autoantibody production and systemic organ damage. A few studies have been conducted for investigating the contribution of IL-21 to the pathogenesis of murine SLE. However, only limited studies have been performed concerning the role of IL-21 in human SLE and the results are still controversial. Objectives: The aim of this study was to evaluate whether IL-21 participates in the pathogenesis of human SLE. Methods: Serum IL-21 levels were measured in SLE, osteoarthritis (OA) patients and healthy controls (HC). Serum IL-21 levels were analyzed for revealing the correlation with laboratory data or a disease activity index for SLE. Kidney tissues from patients with lupus nephritis and controls were used for evaluating the expression of IL-21 and IL-21R. Normal portions of human kidneys removed for renal carcinoma were used as normal controls. Results: Serum levels of IL-21 were increased in the patients with SLE as compared to the patients with OA or HC. Serum IL-21 levels of the patients with SLE were positively correlated with serum levels of IgG, the titers of anti–double-stranded DNA antibodies and the scores of SLE Disease Activity Index. SLE patients with low C4 concentrations had higher serum IL-21 levels than those with normal C4 concentrations. The expression of IL-21 was higher in renal tubular epithelial cells of the patients with lupus nephritis than in those of controls. Conclusions: This study reveals the association between IL-21 and disease activity in the patients with SLE. We also first demonstrate IL-21 expression in renal tissue of the patients with lupus nephritis. These findings suggest that IL-21 is critically implicated in the pathogenesis of SLE. References: Ettinger R, Kuchen S, Lipsky PE: Interleukin 21 as a target of intervention in autoimmune disease. Annals of the rheumatic diseases 2008, 67 Suppl 3:iii83–86. Herber D, Brown TP, Liang S, Young DA, Collins M, Dunussi-Joannopoulos K: IL-21 has a pathogenic role in a lupus-prone mouse model and its blockade with IL-21R.Fc reduces disease progression. Journal of immunology 2007, 178(6):3822–3830. Disclosure of Interest: None declared