Circulating, tumor infiltrating, and lymphoid CXCR5+ CD8 T cells were shown to co-express PD-1 and, in contrast with chronic viral infection (129, 131, 134, 148), TIM-3 (134, 140), however they were functionally less exhausted than the CXCR5− CD8 T cell population and expressed genes related to stem-like plasticity and cytotoxicity (140, 141, 149). The gene discussed is PDCD1; the disease is neoplasm.