Dynamics Of Interferon In The Peripheral Blood Mononuclear Cell From The Patients With Idiopathic Inflammatory Myopathy And Its Clinical Significance

Objective: To explore the expression of interferon-inducible genes(IFIGs) in patients with idiopathic inflammatory myopathies(IIM) and its clinical significance. Methods: The mRNA level of six IFIG gene(OAS-1, IFIT1,IFIT4, IFI44, RASD2 and MX-1) were detected by Real-time quantitative PCR from peripheral blood mononuclear cells of 52 patients with IIM and 20 cases of control. The interferon integral calculation and the corresponding clinical data were analyzed by non-parametric Mann-Whitney and Spearman analysis. Results: 1. The mRNA level of OAS-1, IFIT1, IFIT4,IFI44,RASD2 and MX-1 were significantly increased in IFIG group than normal group(P < 0.0001) as well as interferon integral calculation. 2. The mRNA level of OAS-1, IFIT1, IFIT4, IFI44, RASD2 and MX-1 were significantly higher in 28 patients with dermatomyositis than 24 patients with multiple myositis(P < 0.0001) as well as interferon integral calculation. 3. The mRNA level of MX-1 was significantly elevated in 20 patients with pulmonary interstitial lesions than 32 patients with non-pulmonary interstitial lesions(P < 0.05) as well as interferon integral calculation. 4. Interferon integral calculation was augmented in active period than stable phase in the same patient with IIM(P<0.05). Blood sedimentation was found as an important index of disease activity of IIM. It showed positive correlation between interferon integral calculation and blood sedimentation(P<0.05). 5. There were 30 cases with ANA antibody positive and 22 cases with ANA antibody negative in patients with IIM. Interferon integral calculation was significantly increased in patients with ANA antibody positive(P < 0.05). 7. There was a positive correlation between interferon integral calculation and Jo-1 antibody and Ro-52 antibody positive in patients with IIM. However, there was no positive correlation between interferon integral calculation and CK, AST, LDH and ALT. Conclusion: Although the etiology and pathogenesis of polymyositis were not yet understood entirely well, there is a growing evidence that activation of type I interferon pathway may plays an important role in the development of IIM. This study found that: 1. Interferon integral calculation was increased significantly in the patients with IIM. 2. Interferon integral calculation was augmented in active period than stable phase in the patients with IIM. 3. There was a positive correlation between interferon integral calculation and specific autoantibodies in patients with IIM. 4. Interferon integral calculation may serves as a new biomarker of IIM.