title: Relationship between Serum Level of Interleukin-2 in Patients with Systemic Lupus Erythematosus and Disease Activity in Comparison with Control Group.
abstract: BACKGROUND
  Despite the large number of surveys, there are not any validated biomarkers for SLE disease activity till now. This study aimed to evaluate the relationship between serum level of IL-2 in patients with SLE and disease activity in comparison with control group.
  
  
  METHODS
  In this case-control study, 73 patients with lupus and 73 healthy subjects referred to the rheumatology clinic of 5 Azar Hospital in Gorgan (North of Iran).They were studied via convenience sampling during 2011-2012. Blood samples were taken from both groups and serum levels of interleukin -2 measured by Avi Bion Human IL-2 ELISA kit. Serum Level of IL-2 greater than 15 pg/ml defined positive and lesser than this amount defined negative. Disease activity evaluated with SLE disease activity index. Score greater than or equal to three or four defined as active disease. Data analysis conducted by SPSS software (version 16) and by using descriptive statistics and statistical tests.
  
  
  RESULTS
  Serum level of IL-2 was positive in 45.2% of sample studied and negative in 54.8% in case group, while in control group, serum level of IL-2 only in 11% of sample studied was positive and in 89% was negative. Statistical analysis indicated a significant relationship between serum level of IL-2 and the SLE disease activity index (p=0.025).
  
  
  CONCLUSIONS
  This study showed the relationship between serum levels of IL-2 and disease activity, so this biomarker can be used as a clinical indicator for assessing disease activity in patients with SLE.
authors.affiliation: Assistant Professor, Joint, Bone and Connective Tissue Research Centre (JBCRC), Golesatan University of Medical Sciences , Gorgan, Iran .
authors.forename: Sima
authors.initials: S
authors.lastname: Sedighi
authors.affiliation: Assistant Professor, Joint, Bone and Connective Tissue Research Centre (JBCRC), Golesatan University of Medical Sciences , Gorgan, Iran .
authors.forename: Mehrdad
authors.initials: M
authors.lastname: Aghaei
authors.affiliation: Medical Doctor, University of Medical Sciences , Gorgan, Iran .
authors.forename: Sara
authors.initials: S
authors.lastname: Musavi
authors.affiliation: BSc of Nursing, Clinical Research Development Unit (CRDU), 5 Azar Hospital, Golestan University of Medical Sciences , Gorgan, Iran .
authors.forename: Mahin
authors.initials: M
authors.lastname: Nomali
keywords: Adults; Disease activity; ELISA; Interleukin-2; Systematic lupus erythematosus