Activation of the Interferon Pathway is Dependent upon Autoantibodies in African-American SLE Patients, but not in European-American SLE Patients

Systemic lupus erythematosus (SLE) is a heterogeneous disease which leads to different levels of serum autoantibodies to RNA-binding proteins (anti-RBP) and interferon-α (IFN-α), which plays an important pathogenic role in SLE, between European-American (EA) and African-American (AA) patients. We aimed to explore how IFN-related gene expression pathways differ in patients according to their ancestry and anti-RBP profile Whole blood from 33 female SLE patients and 16 matched controls from EA and AA ancestral backgrounds was analyzed through Affymetrix Gene 1.0 ST gene expression arrays and the data were further studied through Ingenuity Pathways Analysis for canonical pathway comparison. An independent replication cohort of more than 100 SLE patient samples and 30 controls was used to test the hypotheses generated by the microarray data, using qPCR to quantify gene expression.