IL17A and systemic lupus erythematosus: ChIP-qPCR assays showed that the binding levels of all three proteins were decreased significantly when RFX1 was knocked down in normal CD4+ T cells (Fig. 4g–i), whereas the binding of all three proteins to the IL17A promoter was increased significantly when RFX1 was overexpressed in SLE CD4+ T cells (Fig. 4j–l).