AQP1 and myeloid sarcoma: Interestingly, the majority of the 17 patients with NMOSD phenotype (as well as the two MS patients with predominant spinal cord lesions) had antibodies to the extracellular AQP1 domains and bound to the cell-embedded AQP1, whereas all three patients with classical MS profile had exclusively antibodies to the cytoplasmic side of AQP1 and did not bind on the intact AQP1-transfected cells (Table 2).