PDCD1 and myeloid sarcoma: As a result, MS patients had higher frequency of MOG-specific CD8+ T cells, MOG-specific CD8+ TCM, MOG-specific CD8+ TEM, and MOG-specific CD8+ TEMRA, in contrast to a lower frequency of MOG-specific naïve CD8+ T cells; elevated granzyme B expression on MOG-specific CD8+ TCM; and, on MOG-specific CD8+ TEM, elevated granzyme B and reduced PD-1 expression.