Its expression increases by Toll-like receptor 7 (TLR7) stimuli in plasmacytoid DCs from New Zealand Black/White F1 hybrid (NZB/W F1) mice with symptomatic lupus, leading to the expression of the CD40 co-stimulatory molecule required to facilitate the T cell activation [28]. Here, TLR7 is linked to systemic lupus erythematosus.