The exhausted phenotype of TRP1-specific T cells that develop in Ag+GILT-/-Tg mice is further supported by diminished proliferation (Fig 2), diminished cytokine production (Fig 5) [22], high levels of PD-1 expression, which contributes to diminished cytokine production (Figs 4 and 5), and the failure to protect from melanoma challenge and induce vitiligo (Fig 1) [22]. This evidence concerns the gene TYRP1 and melanoma.