Recently, it was reported that IL-33-KO mice develop chronic neurodegeneration and AD-like dementia in late life, and intraperitoneal injection of recombinant IL-33 in IL-33-KO mice induces robust expression of AQP4 in the perivascular astrocyte endfeet and accelerates the drainage of intracerebroventricularly injected peptides [70]. Here, AQP4 is linked to Alzheimer disease.