CD69 and neoplasm: After tumour stimulation in vivo, these tumour‐infiltrating Rag2−/−‐OT1‐iT cells exhibited the typical effector cytotoxic T cells phenotype: CD44high CD62Llow CD69+ CD25+, whereas the splenic Rag2−/−‐OT1‐iT cells showed the memory phenotype (CD44high CD62Lhigh CD69− CD25−).