OBJECTIVETo investigate the role and significance of T help cells 17(Th17) in pathogenesis of idiopathic thrombocytopenic purpura (ITP).

METHODSPeripheral blood samples from ITP patients and normal controls were examined for Th17 cell proportion by flow cytometry (FCM). Expression of IL-17, IL-23, IL-6 and TGF-β1 in hematoplasma was detected by ELISA. The mRNA expression level of IL-17 and RORγt in peripheral blood mononuclear cells (PBMNC) from patients with ITP and normal controls were measured by RT-PCR technique, and expression levels of pSTAT3 and RORγt proteins were analyzed by Western-blot.

RESULTSTh17 cells in peripheral blood from patients with ITP was greatly increased when compared with normal control group (P<0.05). Expressions of IL-17, IL-23, IL-6 and TGF-β1 in hematoplasma of ITP patients were all significantly higher than those in normal control group (all P<0.01). mRNA expression levels of IL-17 and RORγt in PBMNC from patients with ITP were much higher than those in normal controls (P<0.05). Protein expressions of pSTAT3 and RORγt in PBMNC of ITP patients were greatly increased as compared with those in control (P<0.05).

CONCLUSIONTh17 cell subgroup may play a role in incidence and development of ITP, which may participate in the pathogenesis of ITP by increasing Th17 cell proportion and altering the expression level of Th17-related cytokines as well as regulatory and transcriptional factors.