HAVCR2 and autoimmune disease: TIM‐3 also represents a marker of the maturation of natural killer (NK) cells,[6, 32] while its activation correlates with cytokine production[33, 34] and is related to autoimmune diseases.[35] More recently, the role of TIM‐3 in regulating the tumor microenvironment has been particularly pointed out.[36, 37, 38, 39] TIM‐3 is also related to the exhaustion of T‐cells in tumors or to the functionality loss of lymphocytes in some tumor microenvironments.