4‐1BB Delineates Distinct Activation Status of Exhausted Tumor‐Infiltrating CD8+ T Cells in Hepatocellular Carcinoma

Background and Aims Targeting costimulatory receptors with agonistic antibodies is a promising cancer immunotherapy option. We aimed to investigate costimulatory receptor expression, particularly 4‐1BB (CD137 or tumor necrosis factor receptor superfamily member 9), on tumor‐infiltrating CD8 + T cells (CD8 + tumor‐infiltrating lymphocytes [TILs]) and its association with distinct T‐cell activation features among exhausted CD8 + TILs in...