To explore the role of OPN in the pathogenesis of immune thrombocytopenia (ITP) by detecting the content of plasma osteoponetontin (OPN) in patients with primary ITP before and after treatment and in normal controls.

Peripheral venous blood (5 ml) was collected from 40 healthy adults (control group) and 40 ITP patients before and after treatment. The collected samples were centrifuged to separate the plasma. Enzyme-linked immunosorbent assay (ELISA) was used to measure the content of OPN in the samples to observe the expression of OPN in the control group, the pre-treatment group, and the post-treatment group. The correlation was analyzed between platelet count and plasma OPN expression in ITP patients, and OPN contents were compared between the effective group and the ineffective group before and after treatment.

Plasma OPN level in the pre-treatment group was significantly higher than that in the control group (P<0.05). Plasma OPN level in the post-treatment group showed a significantly decreasing trend compared with that the pre-treatment group (P<0.05). There was a significant negative correlation between platelet count and plasma OPN expression in ITP patients (r=-0.80, P<0.05). After treatment, the effective rate was 92.5% (37/40) and the ineffective rate was 7.5% (3/40). The OPN change between before and after treatment was significantly higher in the effective group than in the ineffective group (P<0.05).

OPN may be involved in the pathogenesis of ITP, which is correlated with the degree of thrombocytopenia. Monitoring the change of OPN content between before and after treatment may provide a reference for evaluating the therapeutic efficacy for ITP.