In a mouse model of psoriasis induced by the Toll-like receptor 7 (TLR7) agonist named imiquimod (IMQ), it was shown that IL-17A-producing Vγ4Vδ4 T cells exhibit similarities, suggesting oligoclonal expansion or a common fetal origin of these cells (138, 139). The gene discussed is TLR7; the disease is psoriasis.