This process was not previously investigated in AQP4 + NMOSD, but experimental data highlighted that IGF dysregulation (i.e. reduction) fuels autoimmunity through T reg unbalance,29 and hampers remyelination.30 Astrocytes produce IGF in response to brain injury.31 Therefore, this protective mechanism might be deficient in AQP4 + NMOSD. The gene discussed is AQP4; the disease is Autoimmunity.