CD4-positive, alpha-beta T cell exhausted T cell CD4-positive exhausted alpha-beta T cell 2026-01-13T15:30:05Z exhausted CD4 T cell CD4+ exhausted T lymphocyte exhausted CD4-positive T cell A CD4-positive alpha-beta T cell that displays impaired function and altered differentiation as a result of chronic antigenic stimulation (e.g., chronic infection, tumors, or persistent inflammation). This state is characterised by sustained expression of PD-1 as a shared feature. Additional exhaustion-associated molecules, including the transcription factor TOX, and context- or stage-dependent changes in markers such as LAG-3, TIM-3, CD39, and T-bet, may also be observed; however, the expression levels of these molecules vary depending on exhaustion stage and tissue environment.