Based on a consensus nomenclature for CD8+ T cell phenotypes [50], phenotyping of tumor infiltrating CD8+ T cells at each day of CPR treatment revealed a strongly proliferating (i.e. Ki67+) CD8+ T cell subset expressing numerous molecules associated with both effector (i.e. Perforin, killer cell lectin-like receptor-KLRG1) and memory (i.e. Eomes, low PD-1) T cell status (Fig. 5f) [51]. The gene discussed is PDCD1; the disease is neoplasm.