The distinct expressions of interleukin-15 and interleukin-15 receptor α in Behçet’s disease

• Published in: Rheumatology international Vol. 33; no. 8; pp. 2109 - 2115
• Main Authors: Choe, Jung-Yoon, Lee, Hwajeong, Kim, Sang Gyung, Kim, Min Ji, Park, Sung-Hoon, Kim, Seong-Kyu
• Format: Journal Article
• Language: English
• Published: Berlin/Heidelberg Springer Berlin Heidelberg 01.08.2013
• Subjects: Adult; Aged; Arthritis, Rheumatoid - blood; Behcet Syndrome - blood; Female; Humans; Interleukin-15 - blood; Leukocytes - metabolism; Lupus Erythematosus, Systemic - blood; Male; Medicine; Medicine & Public Health; Middle Aged; Original Article; Receptors, Interleukin-15 - blood; Rheumatology; Interleukin-15; Behçet’s disease; ESR; Interleukin-15 receptor α
• ISSN: 0172-8172; 1437-160X; 1437-160X
• DOI: 10.1007/s00296-013-2705-4

Interleukin-15 (IL-15) is a pleotrophic cytokine that is involved in the pathogenesis of diverse inflammatory rheumatic diseases. The aims of this study were to compare serum IL-15 levels and expression of its receptor (IL-15Rα) in Behçet’s disease (BD) with those in other rheumatic diseases and to identify the relationship between serum IL-15 levels and various clinical parameters in BD. One hundred fifty-eight subjects consisting of 40 BD, 38 systemic lupus erythematosus (SLE), 40 rheumatoid arthritis (RA), and 40 healthy controls were enrolled. Serum IL-15 levels were measured using an enzyme-linked immunosorbent assay. The proportion of IL-15Rα expression on each leukocyte subset was measured by flow cytometry. Erythrocyte sediment rate (ESR) and C-reactive protein (CRP) were measured for each enrolled subject. The clinical activity index of BD was assessed for BD patients. Serum IL-15 levels in BD patients are significantly higher than those of healthy controls, SLE, and RA patients ( p  < 0.001, p  < 0.001, and p  < 0.001, respectively). Serum IL-15 levels in BD were closely related to ESR ( r  = 0.405, p  = 0.027), but not to CRP or the clinical activity index of BD ( p  > 0.05 for both). Additionally, there was no difference in serum IL-15 levels between active and inactive disease states in BD ( p  > 0.05). The proportion of IL-15Rα expression on total leukocytes was much lower for all rheumatic diseases, including BD, than in healthy controls ( p  < 0.01 for SLE, p  < 0.01 for RA, and p  < 0.05 for BD). IL-15 and IL-15Rα system may be involved in the inflammatory process and pathogenesis of BD.