title: [Serum IL-21 level in patients with primary Sjogren's syndrome and clinical significance of IL-21].
abstract: OBJECTIVE
  To investigate the relation between the change of serum IL-21 level and other laboratory indexes by detecting serum IL-21 level from patients with primary Sjogren's syndrome (pSS) and explore the role of IL-21 in pSS.
  
  
  METHODS
  The level of serum IL-21 from 40 pSS patients diagnosed according to 2002 revised international classification criteria for pSS and 30 healthy persons were detected by enzyme-linked immunosorbent assay(ELISA) respectively. Meanwhile, FT3, FT4, TSH, TgAb, TPOAb were detected by Immunochemiluminescent technique. Double diffusion method, Westergren and automatic gel method detected ant-SSA and ant-SSB antibody, ESR and serum protein electrophoresis respectively. The relationship between serum IL-21 level and other clinical symptom of the patients was analyzed.
  
  
  RESULTS
  The level of serum IL-21 in patients with pSS (1051+/-335) ng/L was obviously higher than that in healthy control (466+/-90 ng/L), (P<0.05). The levels of serum IL-21 in the self-antibody positive group, parotid gland swelling pain group, rash group and incorporating hypothyroidism group were higher than those in their negative control groups, and there were significant differences(P<0.05). In addition, The level of serum IL-21 level in pSS patients showed positive correlation with gamma-globulin (r=0.719, P<0.05) and ESR level(r=0.745, P<0.05).
  
  
  CONCLUSIONS
  The evident increase of serum IL-21 level in pSS patients has positive correlation with the levels of gamma-globulin and ESR, which suggests that IL-21 may play a critical role in the pathogenesis of pSS.
authors.affiliation: Department of Rheumatism Immunology, the First Affiliated Hospital of Chinese Medical University, Shenyang 110001, China.
authors.forename: Shuang-long
authors.initials: SL
authors.lastname: Yuan
authors.forename: Li
authors.initials: L
authors.lastname: Jiang
authors.forename: Xiao-li
authors.initials: XL
authors.lastname: Zhang
authors.forename: Shu-fan
authors.initials: SF
authors.lastname: Li
authors.forename: Hong-mei
authors.initials: HM
authors.lastname: Duan
authors.forename: Xiao-fei
authors.initials: XF
authors.lastname: Wang
mesh_terms: D000328:Adult; D004797:Enzyme-Linked Immunosorbent Assay; D005260:Female; D006801:Humans; D007037:Hypothyroidism / Q000097:blood / Q000378:metabolism / Q000473:pathology; D007378:Interleukins / Q000097:blood*; D008297:Male; D008875:Middle Aged; D012859:Sjogren's Syndrome / Q000097:blood* / Q000378:metabolism* / Q000473:pathology; D055815:Young Adult; D005719:gamma-Globulins / Q000378:metabolism; D000098546:Interleukin-21
chemical_list: D007378:Interleukins; D005719:gamma-Globulins; D000098546:Interleukin-21