Summary
Chronic viral infections are characterized by a state of T cell dysfunction that is associated with expression of the PD-1 (programmed cell death 1) inhibitory receptor. A better understanding of the mechanisms that regulate CD8 T cell responses during chronic viral infection is required to improve immunotherapies that will increase T cell function and reduce viral load. We have recently identified a novel population of PD-1+ TCF-1+ virus specific CD8 T cells that act as stem cells to maintain T cell responses during chronic infection of mice with lymphocytic choriomeningitis virus (LCMV). The
