Notably, o22R T cells expanded substantially in the blood, spleen, tumour-draining lymph nodes (TDLNs) and tumour (Extended Data Fig. 4a–e), with increased BrdU incorporation and Ki-67 expression in tumours (Extended Data Fig. 4f,g), indicating an antigen-driven process in vivo. The gene discussed is MKI67; the disease is neoplasm.