IFNA2 and systemic lupus erythematosus: We detected IFN-α in 4 out of the 9 SLE samples analyzed (IFN-α range of 0-10.98pg/ml, mean ± SEM of 1.93 ± 1.20pg/ml for serum, range of 0-11.71 pg/ml, mean of 2.00 ± 1.27pg/ml for BM supernatant).