Expressions of IL-18 and its binding protein in peripheral blood leukocytes and kidney tissues of lupus nephritis patients.
To investigate the expressions of IL-18 and its binding protein (IL-18BP) in peripheral blood leukocytes and kidney tissues in patients with lupus nephritis (LN). SYBR-green-dye-I-based real-time quantitative PCR method was used to compare the gene expression levels (indicated as 2(-DeltaDeltaCT) value) of IL-18 and IL-18BP in the peripheral blood leucocytes of LN patients and those in normal controls. Serum levels of IL-18 were measured with ELISA method. Immunohistochemical evaluation of IL-18 and Il-18BP expression in LN was carried out on frozen renal biopsy sections. IL-18BP mRNA expression levels in LN patients were significantly lower than those of normal controls (P < 0.01). Serum levels of IL-18 in LN patients were significantly higher than those of normal controls (P < 0.01). It is noticeable that serum IL-18 levels in the patients treated with glucocorticoids and cyclophosphamide was lower than those treated with glucocorticoids only or glucocorticoids and other immune inhibitors such as chloroquine/hydroxychloroquine and azathioprine. Expression of IL-18 in renal glomeruli was higher in type-IV and type-V LN patients than in type-III LN patients. LN patients present lower IL-18BP mRNA expression and higher serum levels of IL-18 than those in normal controls. The preponderance of IL-18 in glomeruli from LN patients indicates IL-18 may be concerned with the local inflammation. Up-regulation of IL-18BP expression and control of the biological activity of IL-18 may be a therapeutic approach to LN patients.
Department of Rheumatology, Renji Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, 20001, China. hudawei@medmail.com.cn
Dawei
D
Hu
Xiaoqian
X
Liu
Shunle
S
Chen
Chunde
C
Bao
D000328:Adult; D005260:Female; D005786:Gene Expression Regulation; D006801:Humans; D007150:Immunohistochemistry; D036341:Intercellular Signaling Peptides and Proteins / Q000097:blood / Q000235:genetics / Q000276:immunology*; D020382:Interleukin-18 / Q000097:blood / Q000235:genetics / Q000276:immunology*; D007668:Kidney / Q000276:immunology*; D007963:Leukocytes, Mononuclear / Q000276:immunology*; D008181:Lupus Nephritis / Q000276:immunology*; D008297:Male; D012333:RNA, Messenger / Q000378:metabolism; D020133:Reverse Transcriptase Polymerase Chain Reaction
D036341:Intercellular Signaling Peptides and Proteins; D020382:Interleukin-18; D012333:RNA, Messenger; C118370:interleukin-18 binding protein