CD4 and myeloid sarcoma: Finally, while anti-CD4 monoclonal antibody treatment failed to alter disease course in MS patients [13], treatment with alemtuzumab [14], a monoclonal antibody that depletes both CD8+ and CD4+ T cells, or treatment with natalizumab [15], [16], which prevents both CD8+ and CD4+ T cell trafficking into the CNS, resulted in a reduction in relapse rate.