Another previous study performed by Alexopoulos et al. concluded that AQP4 antibodies could be present in SLE patients and persist for many years, without concurrent clinical or radiological NMOSD signs, and the authors explained this to be due to the induced complement-mediated damage in cultured astrocytes in these patients, similar to the damage induced by antibodies obtained from typical NMO patients [24]. Here, AQP4 is linked to neuromyelitis optica.