PDCD1 and myeloid sarcoma: Indeed, CD49d+ CD8+ T lymphocytes invading the MS brain exhibited a pro-inflammatory effector phenotype, expressing CD137 and CD95L, as well as inhibitory receptors TIM-3 and PD-1 on their surface, in addition to the transcriptional factor EOMES (12, 14, 19, 143) (Figure 2).