In addition, because of findings related to AQP4 antibodies, it is clear that B cell–mediated humoral immunity plays an important role in the pathogenesis of NMOSD.38, 39, 40 In some human autoimmune diseases, there is a lack of equivalent Breg cells with regard to quantity or function.41 An interesting finding was that IL‐35 was also correlated with the number of Breg cells.22 Wang et al studied Breg cells and IL‐35 cytokines and found that IL‐35 induced Breg cells to produce IL‐10 and IL‐35 (IL‐35+ Breg cells). The gene discussed is AQP4; the disease is autoimmune disease.