PDCD1 and neoplasm: In Rag1−/− mice co-transplanted with RAMP1-expressing and -non-expressing CD8+ T cells, we found that within the same tumour, the relative proportion of intratumoral PD-1+LAG3+TIM3+ CD8+ T cells was lower in Ramp1−/− CD8+ T cells (Fig 5b and Extended Data Fig. 10w).