PDCD1 and neoplasm: In vitro pre‐activated T cells share main characteristics of antigen‐experienced T cells within the tumor microenvironment, such as upregulation of exhaustion markers PD‐1, TIM‐3, LAG‐3, and CTLA‐4 (Andrews et al. 2024; Crawford and Wherry 2009; Lak et al. 2022) as well as enhanced IL‐12Rβ1 expression.