Nevertheless, the potential importance of γδ T-cells to psoriasis pathophysiology has been supported by reports demonstrating IL-17A production by γδ T-cells within lesions [34,39,40], by the association between reduced abundance of γδ T-cells in the blood and severity of psoriasis [36], and by the restoration of γδ T-cell numbers in the blood following successful treatment of psoriasis with systemic therapies [36]. Here, IL17A is linked to psoriasis.