title: Decreased expression of IL-33 in immune thrombocytopenia.
abstract: OBJECTIVE
  Interleukin-33 (IL-33) is an IL-1 family cytokine which signals via its ST2 receptor and is involved in several autoimmune diseases by regulating T cell immune responses. This study aims to measure the expression of soluble ST2 (sST2) and IL-33 in active immune thrombocytopenia (ITP) and during remission.
  
  
  METHODS
  Thirty-two ITP patients with active disease and 20 patients in remission were studied. IL-33 and sST2 were measured in plasma using ELISA and compared with 27 age- and sex-matched healthy controls. Real-time quantitative PCR was used to determine IL-33 and sST2 mRNA expressions.
  
  
  RESULTS
  The IL-33 level in plasma was significantly down-regulated in the patients with active ITP (P<0.01). The sST2 level was up-regulated (P<0.01) in the patients with active ITP compared with ITP in remission and the normal controls. No significant changes were detected between the patients with ITP in remission and the normal controls. We detected an obvious up-regulation of sST2 mRNA levels but no change in IL-33 mRNA expression. There was no correlation observed between IL-33 or sST2 expression and the platelet count of the patients with active ITP. The plasma and mRNA level ratios of sST2/IL-33 were up-regulated in the active disease patients (P<0.01). However, no difference was detected between the ITP patients with remission disease and healthy controls.
  
  
  CONCLUSIONS
  The values of sST2 and IL-33 observed in patients with ITP correlated with disease activity. Considering the role of IL-33 in regulating T cell immunity, studies on IL-33 and sST2 in ITP would further improve our understanding of the pathogenesis of ITP.
authors.affiliation: Department of Hematology, Shandong Provincial Hospital Affiliated to Shandong University, 324 Jing Wu Rd, Jinan, People's Republic of China.
authors.forename: Pei-Pei
authors.initials: PP
authors.lastname: Li
authors.affiliation: Department of Hematology, People's Hospital of Rizhao City, 126 taian Rd, Rizhao, People's Republic of China.
authors.forename: Xiao-Mei
authors.initials: XM
authors.lastname: Zhang
authors.affiliation: Department of Hematology, Shandong Provincial Hospital Affiliated to Shandong University, 324 Jing Wu Rd, Jinan, People's Republic of China.
authors.forename: Dai
authors.initials: D
authors.lastname: Yuan
authors.affiliation: Department of Hematology, Shandong Provincial Hospital Affiliated to Shandong University, 324 Jing Wu Rd, Jinan, People's Republic of China.
authors.forename: Xin
authors.initials: X
authors.lastname: Liu
authors.affiliation: Department of Hematology, Shandong Provincial Hospital Affiliated to Shandong University, 324 Jing Wu Rd, Jinan, People's Republic of China.
authors.forename: Ying
authors.initials: Y
authors.lastname: Li
authors.affiliation: Department of Hematology, Shandong Provincial Hospital Affiliated to Shandong University, 324 Jing Wu Rd, Jinan, People's Republic of China. Electronic address: snning@126.com.
authors.forename: Ning-Ning
authors.initials: NN
authors.lastname: Shan
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D005260:Female; D006801:Humans; D000072179:Interleukin-1 Receptor-Like 1 Protein; D000067596:Interleukin-33 / Q000097:blood* / Q000235:genetics; D008297:Male; D008875:Middle Aged; D010976:Platelet Count; D016553:Purpura, Thrombocytopenic, Idiopathic / Q000097:blood*; D012333:RNA, Messenger / Q000378:metabolism; D011956:Receptors, Cell Surface / Q000097:blood / Q000235:genetics; D055815:Young Adult
chemical_list: C079241:IL1RL1 protein, human; C506536:IL33 protein, human; D000072179:Interleukin-1 Receptor-Like 1 Protein; D000067596:Interleukin-33; D012333:RNA, Messenger; D011956:Receptors, Cell Surface
keywords: Cytokine; IL-33; Immune thrombocytopenia; Th1/Th2; sST2