Expression patterns of Th1 and Th2 cytokine genes in childhood idiopathic thrombocytopenic purpura (ITP) at presentation and their modulation by intravenous immunoglobulin G (IVIg) treatment: their role in prognosis.
Childhood idiopathic thrombocytopenic purpura (ITP) resolves usually after the first episode, although it may recur, and in 10% to 20% of patients develops into a chronic disorder. Evidence of the immunoregulatory role of Th1/Th2 responses in autoimmune diseases prompted us to perform a prospective study of Th1/Th2 gene expression profiles and transforming growth factor beta (TGF-beta) plasma levels in 18 children (median age, 6.4 years) with acute ITP, before and after intravenous immunoglobulin G (IVIg) infusion, and during a follow-up period (0.5-5 years). Initially, 12 of 18 patients had either low Th0/Th1 plus interleukin 10 (IL-10) or no in vivo cytokine gene expression (0). At 24 hours after IVIg infusion this pattern became 0 or Th2 (9 of 12) or remained low Th0/Th1 (3 of 12). During follow-up these patients did not relapse and maintained 0 or Th2 pattern without IL-10. Of the remaining 6 patients, 4 presented with a Th1 or Th0/Th1 pattern plus IL-10 that persisted after IVIg treatment (although interferon gamma [IFN-gamma] expression diminished) and stabilized to Th1 plus IL-10 at follow-up, which was marked by infrequent episodes of ITP. Two patients presenting with a strict Th1 pattern characterized by high expression of IFN-gamma, which remained unchanged after IVIg and at follow-up, can be characterized as chronic ITP. TGF-beta plasma levels were low in patients with active disease and increased in remission. Overall, acute ITP presents with Th1, Th0/Th1, or 0 in vivo cytokine gene expression. Stable remission is associated with a 0 or Th2 pattern. A 0 or Th2 pattern after IVIg gave the best prognosis, whereas sustained high expression of IFN-gamma and refractoriness to IVIg were the main indicators of poor prognosis.
Mouzaki
Athanasia
A
Laboratory Hematology and Transfusion Medicine, School of Medicine, Patras University, Greece. mouzaki@med.upatras.gr
Theodoropoulou
Maria
M
Gianakopoulos
Ioannis
I
Vlaha
Vassiliki
V
Kyrtsonis
Maria-Christina
MC
Maniatis
Alice
A
D002648:Child; D002675:Child, Preschool; D016207:Cytokines / Q000235:genetics* / Q000276:immunology*; D005260:Female; D020869:Gene Expression Profiling; D005786:Gene Expression Regulation / Q000187:drug effects / Q000276:immunology*; D006801:Humans; D016756:Immunoglobulins, Intravenous / Q000008:administration & dosage / Q000235:genetics* / Q000276:immunology*; D007223:Infant; D008297:Male; D011379:Prognosis; D016553:Purpura, Thrombocytopenic, Idiopathic / Q000188:drug therapy / Q000235:genetics* / Q000276:immunology*; D018417:Th1 Cells / Q000276:immunology*; D018418:Th2 Cells / Q000276:immunology*
D016207:Cytokines; D016756:Immunoglobulins, Intravenous