The authors found that the clonotypes of tumor-infiltrating CD8+ T cells after anti-PD-1 therapy were phenotypically enriched with activation/dysfunction-associated markers including TH1-associated cytokines (TNFα, IFNγ), checkpoint receptors (PD-1, TIM-3, LAG-3), and CD103. The gene discussed is PDCD1; the disease is neoplasm.