TLR7 and vitiligo: In contrast, recent evidences suggest that type I IFNs play a role in vitiligo pathogenesis: IFN-α producing plasmacytoid dendritic cells infiltrate active vitiligo skin (16, 36); pegylated IFN-α2a and IFN-α2b, which are used in the treatment of chronic hepatitis C, induce depigmentation at the injection sites (37), and vitiligo patches have been observed at the site of application of imiquimod, a Toll-like receptor (TLR)-7 and TLR-8 agonist that enhances IFN-α production (16).