title: Profiling the expression of interleukin (IL)-28 and IL-28 receptor α in systemic lupus erythematosus patients.
abstract: BACKGROUND
  Interleukin (IL)-28 is an interferon-λ-family member involved in immunity against viral infection and tumour. We here determined the expression profiles of IL-28 and IL-28 receptor α (IL-28RA) in patients with systemic lupus erythematosus (SLE) to evaluate the possibility that IL-28 is linked to the pathogenesis of SLE.
  
  
  METHODS
  The serum IL-28 protein levels were determined by ELISA, and the IL-28 and IL-28RA transcript levels in peripheral blood mononuclear cells (PBMCs) and peripheral blood T cells were determined by RT-PCR. The levels in patients with SLE with the active disease activity were statistically compared with those in normal controls.
  
  
  RESULTS
  IL-28 protein in sera and IL-28 transcripts in PBMCs and unactivated T cells were detectable only in some individuals, and IL-28 transcripts in T cells were induced by cell activation with anti-CD2, anti-CD3 and anti-CD28 antibodies. However, compared with normal controls, patients with SLE more frequently had detectable IL-28 protein in serum and had the higher IL-28 transcript levels in activated CD4(+) T cells, but not activated CD8(+) T cells. Two IL-28RA transcripts isoforms were detected in PBMCs and T cells, and their levels in patients with SLE were comparable with those in normal controls.
  
  
  CONCLUSIONS
  The expression of IL-28, a T-cell autocrine factor, is dysregulated in patients with SLE, supporting the possibility that IL-28 may contribute to some of the SLE pathogenesis.
authors.affiliation: Department of Internal Medicine, Cathay General Hospital, Taipei, Taiwan. sclin@cgh.org.tw
authors.forename: Shih-Chang
authors.initials: SC
authors.lastname: Lin
authors.forename: Chia-Chen
authors.initials: CC
authors.lastname: Kuo
authors.forename: Jeng-Ting
authors.initials: JT
authors.lastname: Tsao
authors.forename: Li-Jing
authors.initials: LJ
authors.lastname: Lin
mesh_terms: D000328:Adult; D016022:Case-Control Studies; D016009:Chi-Square Distribution; D004797:Enzyme-Linked Immunosorbent Assay; D005260:Female; D020869:Gene Expression Profiling; D006801:Humans; D007378:Interleukins / Q000097:blood / Q000235:genetics*; D008180:Lupus Erythematosus, Systemic / Q000097:blood / Q000235:genetics*; D008297:Male; D018121:Receptors, Cytokine / Q000097:blood / Q000235:genetics*; D020133:Reverse Transcriptase Polymerase Chain Reaction; D012720:Severity of Illness Index; D013601:T-Lymphocytes / Q000276:immunology; D013624:Taiwan; D000095022:Interferon Lambda
chemical_list: D007378:Interleukins; D018121:Receptors, Cytokine; C000624353:interferon-lambda, human; D000095022:Interferon Lambda; C471046:interleukin 28alpha receptor