Aquaporin 4 Antibody: APC

Aquaporin 4 (AQP4) is a key water channel protein predominantly expressed in the central nervous system, where it plays a critical role in maintaining brain water balance. While it is also found in the basolateral membrane of renal collecting duct cells, its most significant physiological and pathological functions are observed in the brain, particularly in astrocyte endfeet at the blood-brain barrier and around brain ventricles. AQP4 facilitates bidirectional water transport in response to osmotic gradients, contributing to cerebrospinal fluid dynamics, neurovascular coupling, and the clearance of metabolic waste via the glymphatic system. Its expression is rapidly upregulated in response to central nervous system (CNS) injury, including trauma, ischemia, and neuroinflammation, making it a key player in the development of cerebral edema and gliosis. Importantly, AQP4 is the primary autoimmune target in neuromyelitis optica spectrum disorder (NMOSD), a severe inflammatory demyelinating disease of the CNS. Autoantibodies against AQP4 (AQP4-IgG) lead to astrocyte damage, blood-brain barrier disruption, and secondary neuronal injury. Beyond NMOSD, dysregulation of AQP4 has been implicated in Alzheimer’s disease, Parkinson’s disease, and multiple sclerosis, where impaired water clearance and neuroinflammation contribute to disease progression. As such, AQP4 is increasingly recognized as a promising biomarker and therapeutic target in neurodegenerative disease research.

Aquaporin 4, Aquaporin-4, AQP4, AQP-4, AQP 4, AQP4_HUMAN, Aquaporin type 4, Aquaporin4, HMIWC 2, HMIWC2, Mercurial insensitive water channel, Mercurial-insensitive water channel, MGC22454, MIWC, WCH 4, WCH4

0.5 µg/ml of SPC-505 was sufficient for detection of aquaporin 4 in 10 µg of rat kidney tissue lysate by colorimetric immunoblot analysis using Goat anti-rabbit IgG:HRP as the secondary antibody.

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