title: The potential role of interferon-regulatory factor 7 among Taiwanese patients with systemic lupus erythematosus.
abstract: OBJECTIVE
  Type I interferons (IFN), especially IFN-α, have been proposed to underlie the pathogenesis of systemic lupus erythematosus (SLE). Members of the IFN regulatory factor (IRF) family, which regulate IFN expression, have been implicated as risk factors for SLE. Our aims were to investigate the expression of IRF7 and its correlation with disease activity and to explore the association in Taiwanese patients between 2 genetic single-nucleotide polymorphisms (SNP) of IRF7 and SLE.
  
  
  METHODS
  IRF7 messenger RNA (mRNA) levels were measured in peripheral blood mononuclear cells by real-time reverse transcription polymerase chain reaction in 51 adult patients with SLE and 65 age-matched and sex-matched controls. Their serum IFN-α levels were determined by ELISA and the clinical manifestations were recorded at the same time. Two IRF7 SNP, rs1061501 and rs1061502, were examined by genotyping across 92 patients with SLE and 92 age and sex-matched healthy control subjects.
  
  
  RESULTS
  Compared with controls, the expression of IRF7 mRNA was significantly increased in patients with SLE and was positively correlated with both the serum level of IFN-α and lupus disease activity. The distribution of SNP rs1061501 by genotype (CC, CT, and TT) and by allele (C, T) was significantly different between the SLE and the control group (p = 0.028 for genotype and p = 0.009 for allele). There were no significant differences for SNP rs1061502.
  
  
  CONCLUSIONS
  The results suggest that dysregulation of IRF7 might mediate an excessive production of IFN-α, which then exerts a crucial effect on the pathogenesis of human SLE. The IRF7 SNP rs1061501 TT genotype and T allele are enriched in Taiwanese patients with SLE and thus would seem to be associated with an increased risk of developing SLE.
authors.affiliation: Section of Rheumatology and Immunology, Department of Internal Medicine, National Cheng Kung University Hospital, 138 Sheng Li Road, Tainan, Taiwan 704, Republic of China.
authors.forename: Li-Hsin
authors.initials: LH
authors.lastname: Lin
authors.forename: Pin
authors.initials: P
authors.lastname: Ling
authors.forename: Ming-Fei
authors.initials: MF
authors.lastname: Liu
mesh_terms: D000328:Adult; D005260:Female; D005787:Gene Frequency; D020022:Genetic Predisposition to Disease / Q000208:ethnology / Q000235:genetics; D005838:Genotype; D006801:Humans; D050839:Interferon Regulatory Factor-7 / Q000235:genetics / Q000502:physiology*; D016898:Interferon-alpha / Q000097:blood; D007963:Leukocytes, Mononuclear / Q000276:immunology; D008180:Lupus Erythematosus, Systemic / Q000208:ethnology / Q000235:genetics* / Q000276:immunology*; D008297:Male; D008875:Middle Aged; D020641:Polymorphism, Single Nucleotide / Q000276:immunology; D012307:Risk Factors; D013624:Taiwan / Q000453:epidemiology
chemical_list: C494234:IRF7 protein, human; D050839:Interferon Regulatory Factor-7; D016898:Interferon-alpha