Increasing evidence has shown that miRNA-451a (miR-451a) is associated with the development of systemic lupus erythematosus (SLE); however, the mechanism of this association is not fully known. The present study found an increased expression of miR-451a in the spleen and thymus of an SLE mice model. A decrease in miR-451a expression partly relieved the enlargement of the spleen and decreased the proteinuria content and immune complex deposits. The deficiency in miR-451a also decreased numbers of CD4+CD69+ and CD4+/CD8+ T cells and the levels of the serum cytokines IL-17a and IL-4. The IFN regulatory factor (IRF) 8 was highly expressed in the immune organs of wild-type mice but was suppressed in SLE-like mice. A dual-luciferase reporter assay was carried out in combination with gene silencing and overexpression to verify that IRF8 was a target of miR-451a in vitro and in vivo. The data indicate the function and a target of miR-451a in SLE, providing a new target for SLE therapy.
Keywords: IFN regulatory factor 8; cytokines; immune complex deposit; miRNA-451a; systemic lupus erythematosus.