The relative length of CD31+ vasculature covered by AQP4 was higher in zanubrutinib-treated (only in 20 mg/kg zanubrutinib but not in 5 or 10 mg/kg zanubrutinib) NMO mice compared with untreated NMO mice (Fig. 3H, I). This evidence concerns the gene AQP4 and neuromyelitis optica.