PhosphoSolutions New Logo Blue with White Antibody

Our sister company, PhosphoSolutions, was founded in 2001 by Drs. Michael D. Browning, John W. Haycock, and Andrew J. Czernik, who all worked together in the laboratory of Dr. Paul Greengard. Dr. Greengard was a co-recipient of the 2000 Nobel Prize in Medicine for his work on the role of protein phosphorylation in signal transduction in the nervous system.

Their expertise led to the development of a portfolio of over 300 antibodies — including 125 phospho-specific antibodies — focused primarily in the neuroscience field.

PhosphoSolutions also offers custom services using their expertise in phospho-specific antibody development to researchers.

One of their most recent products, Anti-AQP4 Antibody (Catalog 134-AQP4), is now available. Aquaporin-4 (AQP4) a bidirectional water channel protein is the most expressed aquaporin within the central nervous system. AQP4 is predominantly expressed by astrocytes and ependymal cells within the blood-brain-barrier and ependymal-cerebrospinal fluid barriers (Verkman, et al 2011).

AQP4 plays a role in synaptic plasticity (Skucas et al, 2011), astrocyte mitigation (Saadoun et al, 2005), and K+ homeostasis (Binder et al, 2006). Due to the significant role AQP4 plays in cognition, it has been reported to be dysregulated in several neurological disorders. Alzheimer’s patients have amyloid deposits in the walls of the vasculature known as CAA which causes AQP4 mis-location (Wilcock et al, 2009). Patients with Parkinson’s disease have low levels of AQP4 expression which leads to reduced inflammatory response (Chi et al,2011). Reduced levels of AQP4 in traumatic brain injury affects both the acute stage, decreasing the ability to remove excess water from the brain, and in the later stage, by preventing cellular damage and swelling (Zhang et al, 2015).

AQP4 is available in two sizes, 100 µl and 25 µl.

The AQP4 antibody was designed against a peptide antigen from the amino acids residues within the C-terminal region of the rat AQP4 and conjugated to the keyhole limpet hemocyanin (KLH). The affinity purified antibody is specific for endogenous levels of the ~35 kDa AQP4 protein.

To learn more information about Anti-AQP4 Antibody, visit PhosphoSolutions Anti-AQP4 product page.

Western blot of rat whole brain lysate AQP4 antibody


For more information regarding PhosphoSolutions products, please visit their website at

General References:

Verkman, A.S., 2011. Aquaporins at a glance. Journal of Cell Science, 124(13), pp.2107-2112.

Skucas, V.A., Mathews, I.B., Yang, J., Cheng, Q., Treister, A., Duffy, A.M., Verkman, A.S., Hempstead, B.L., Wood, M.A., Binder, D.K. and Scharfman, H.E., 2011. Impairment of select forms of spatial memory and neurotrophin-dependent synaptic plasticity by deletion of glial aquaporin-4. Journal of Neuroscience, 31(17), pp.6392-6397.

Saadoun, S., Papadopoulos, M.C., Watanabe, H., Yan, D., Manley, G.T. and Verkman, A.S., 2005. Involvement of aquaporin-4 in astroglial cell migration and glial scar formation. Journal of Cell Science, 118(24), pp.5691-5698.

Binder, D.K., Yao, X., Zador, Z., Sick, T.J., Verkman, A.S. and Manley, G.T., 2006. Increased seizure duration and slowed potassium kinetics in mice lacking aquaporin‐4 water channels. Glia, 53(6), pp.631-636.

Wilcock, D.M., Vitek, M.P. and Colton, C.A., 2009. Vascular amyloid alters astrocytic water and potassium channels in mouse models and humans with Alzheimer's disease. Neuroscience, 159(3), pp.1055-1069.

Chi, Y., Fan, Y., He, L., Liu, W., Wen, X., Zhou, S., Wang, X., Zhang, C., Kong, H., Sonoda, L. and Tripathi, P., 2011. Novel role of aquaporin‐4 in CD4+ CD25+ T regulatory cell development and severity of Parkinson’s disease. Aging Cell, 10(3), pp.368-382.

Zhang, C., Chen, J. and Lu, H., 2015. Expression of aquaporin-4 and pathological characteristics of brain injury in a rat model of traumatic brain injury. Molecular Medicine Reports, 12(5), pp.7351-7357.

News / announcements