In the context of human PV (11) and psoriatic arthritis (33), MAIT cells have been evaluated in skin samples and synovial fluid, respectively, using TRAV1-2, CD161 and IL-18Rα as surrogate markers that relatively accurately estimate CD8+ and DN, but not CD4+ and DP MAIT cells. This evidence concerns the gene TRAV1-2 and psoriatic arthritis.