Furthermore, a single administration of a monoclonal antibody targeting BDCA2, a plasmacytoid dendritic cell (pDC)-specific receptor that inhibits the production of IFN, decreased the expression of IIGs in whole blood cells and reduced active cutaneous lesions in patients with SLE [39], while other studies showed that circulating pDC from SLE patients had impaired IFN production compared to that of healthy controls and the number of pDC was not associated with blood IIGs expression levels [40, 41]. This evidence concerns the gene CLEC4C and systemic lupus erythematosus.