AQP4

AQP4, predominantly expressed in central nervous system astrocytes, is essential for water and potassium ion homeostasis in the brain. This protein forms channels that facilitate rapid water transport across cell membranes, influencing cerebrospinal fluid dynamics and neural environment stability. AQP4's expression is a key biomarker for neurological disorders such as cerebral edema, ischemic stroke, and neuroinflammation, and it is particularly implicated in the pathology of neuromyelitis optica spectrum disorder (NMOSD), with lesion distribution in affected patients closely aligning with AQP4's presence, often in the optic nerve, spinal cord, diencephalon, and hindbrain. AQP4 is pivotal for diagnosing and treating central nervous system diseases.