In fact, the majority of MS patients benefits from IFN-β therapy [45]; that is, pDCs from MS patients produce lower levels of IFN-α compared to those derived by healthy donors [15], and the serum levels of type I IFN as well as the response of PBMC to type I IFN in MS are lower compared to SLE patients [46]. This evidence concerns the gene IFNA1 and systemic lupus erythematosus.