CD8A and myeloid sarcoma: Similarly, PD-1 depletion in lymphocytes derived from MS patients during the acute phase was associated with a proliferative effect on CD4+ and CD8+ T cells; nevertheless, these consequences were not evidenced while PD-L1 on the APCs was suppressed, suggesting that PD-1 has a more prominent role than PD-L1 in inducing lymphocyte apoptosis and enhancing lymphocyte proliferation in MS [47].