T cell exhaustion (null)

T cell exhaustion is a dysfunctional cellular state that arises during chronic antigen exposure, notably in persistent infections and cancer, characterized by the progressive loss of proliferative capacity, effector functions (such as cytokine production and cytotoxicity), distinct transcriptional and epigenetic programs, and sustained high expression of multiple inhibitory receptors, especially PD-1, CTLA-4, TIM-3, and LAG-3[1][2][3][6][9]. Unlike T cell anergy or senescence, exhaustion is reversible to some extent, particularly by immune checkpoint blockade therapies[4][5]. Exhaustion limits potentially harmful inflammation but impairs the immune system's ability to control chronic disease, making reversal of T cell exhaustion a central focus in immuno-oncology and antiviral therapy research[2][5]. Note: "T cell exhaustion" refers to a cellular state or phenotype, not an individual molecule or receptor. While not a molecular target, the inhibitory receptors that define and sustain T cell exhaustion (e.g., PD-1, CTLA-4, LAG-3, Tim-3) are frequently targeted in drug development[10]. In databases of therapeutic targets, it is more appropriate to define the targets as "Programmed cell death protein 1 (PD-1)", "Cytotoxic T-lymphocyte–associated protein 4 (CTLA-4)", etc., rather than the exhaustion state itself. Therefore, this entry should be marked is_incorrect: true for the purposes of molecular target abstraction.

Other names

T-cell dysfunctionT-cell anergy (sometimes used imprecisely as an alias, but technically different)Tex (for exhausted T cells)

Immune checkpoint blockade (PD-1/PD-L1, CTLA-4, LAG-3 or Tim-3 antibody inhibitors that restore effector T cell function by blocking inhibitory receptors)