[Changes of IL-21 and Its Mediated JAK/STAT Signaling Pathway in Patients with Immune Thrombocytopenia].

To explore the correlation between JAK/STAT signaling pathways and pathogenesis of immune thrombocytopenia(ITP).Twenty-six newly-diagnosed ITP patients was included in this study. They all meet the clinical and hematological criteria for the diagnosis of ITP, and patients with coronary heart disease, severe refractory hypertension, diabetes or with severe liver or kidney function incompetence were ruled out. 24 healthy control without autoimmune diseases, viral infectious diseases and with normal liver and kidney functions were also included. The expressions of Jak3, p-Jak3 mRNA, Stat3, and p-Stat3 were tested and the changes in levels of IL-21 mRNA, IL-21 cell secretion after DEX intervention and AG490 blockade were measured.Compared with the healthy control, patients with ITP had significantly high expressions of Jak3, p-Jak3 mRNA, Stat3 and p-Stat3 protein, which significantly reduced after AG490 blocking (P<0.01). The expression of IL-21 mRNA and the secretion of IL-21 obviously decreased after DEX intervention, but increased after AG490 blocking(P<0.01).The pathogenesis of ITP associates with the activation of JAK/STAT signaling pathways, and IL-21-mediated JAK/STAT signaling pathways play regulatory role in ITP.