title: Increased expression of soluble cytotoxic T-lymphocyte-associated antigen-4 molecule in patients with systemic lupus erythematosus.
abstract: A soluble form of cytotoxic T-lymphocyte-associated antigen-4 (sCTLA-4) was recently found and shown to possess a downregulatory function as a membrane-bound CTLA-4 molecule. The purpose of the study was to investigate the expression of sCTLA-4 molecule in patients with systemic lupus erythematosus (SLE). One hundred patients with SLE and 40 age- and sex-matched healthy individuals were enrolled in the study. The results showed that patients with SLE have significantly higher levels of sCTLA-4 in sera than healthy controls (21.6 +/- 12.3 ng/ml versus 5.9 +/- 5.4 ng/ml, P < 0.001). Increased expression of sCTLA-4 mRNA in peripheral blood mononuclear cells (PBMCs) was also found in SLE patients. However, we could not find a statistically significant correlation between the serum levels of sCTLA-4 and lupus disease activities. The reported CTLA-4 gene polymorphism in promoter region at position -318 did not affect the levels of sCTLA-4. To the best of our knowledge, this is the first report showing that patients with SLE have increased sCTLA-4 expression. However, the mechanism and role of increased sCTLA-4 in the pathogenesis of SLE remains elucidated.
authors.affiliation: Section of Rheumatology and Immunology, Department of Internal Medicine, College of Medicine, National Cheng Kung University, Tainan, Taiwan, ROC. mfliu@mail.ncku.edu.tw
authors.forename: M-F
authors.initials: MF
authors.lastname: Liu
authors.forename: C-R
authors.initials: CR
authors.lastname: Wang
authors.forename: P-C
authors.initials: PC
authors.lastname: Chen
authors.forename: L-L
authors.initials: LL
authors.lastname: Fung
mesh_terms: D000069594:Abatacept; D015703:Antigens, CD; D000943:Antigens, Differentiation / Q000097:blood* / Q000235:genetics; D001483:Base Sequence; D060908:CTLA-4 Antigen; D016022:Case-Control Studies; D005260:Female; D015870:Gene Expression; D006801:Humans; D018796:Immunoconjugates; D008180:Lupus Erythematosus, Systemic / Q000235:genetics / Q000276:immunology*; D008297:Male; D011110:Polymorphism, Genetic; D011401:Promoter Regions, Genetic; D012333:RNA, Messenger / Q000097:blood / Q000235:genetics; D012995:Solubility
chemical_list: D015703:Antigens, CD; D000943:Antigens, Differentiation; D060908:CTLA-4 Antigen; C556706:CTLA4 protein, human; D018796:Immunoconjugates; D012333:RNA, Messenger; D000069594:Abatacept