|Human, Mouse, Rat|
Application Methods: Immunofluorescence (Frozen), Immunohistochemistry (Paraffin), Immunoprecipitation, Western Blotting
Background: Aquaporins (AQP) are integral membrane proteins that serve as channels in the transfer of water and small solutes across the membrane. There are 13 isoforms of AQP that express in different types of cells and tissues (1,2). AQP1 is found in blood vessels, kidney, eye, and ear. AQP2 is found in the kidney, and it has been shown that the lack of AQP2 results in diabetes (1,3). AQP4 is present in the brain, where it is enriched in astrocytes (1,2,4). AQP5 is found in the salivary and lacrimal gland, AQP6 in intracellular vesicles in the kidney, AQP7 in adipocytes, AQP8 in kidney, testis, and liver, AQP9 is present in liver and leukocytes and AQP10-11 in the intestine (1,3,4). AQPs are essential for the function of cells and organs. It has been shown that AQP1 and AQP4 regulate the water homeostasis in astrocytes, preventing cerebral edema caused by solute imbalance (5). Several studies have shown the involvement of AQPs in the development of inflammatory processes, including cells of innate and adaptive immunity (6,7).
Application Methods: Immunoprecipitation, Western Blotting
Background: Podoplanin (aggrus, glycoprotein 36) is a single-pass transmembrane protein belonging to the type-1 family of sialomucin-like glycoproteins. Podoplanin was first described in the rat as a surface glycoprotein that regulated podocyte morphology (1). It is now commonly used as a marker of lymphatic endothelial cells, where its expression is associated with the process of lymphangiogenesis (2). Its role in this regard is presumably due to its putative involvement in regulating actin cytoskeleton dynamics (3). Research studies have shown that podoplanin expression is upregulated in a number of tumor types including colorectal cancers (4), oral squamous cell carcinomas (5), and germ cell tumors (6), with higher expression levels often associated with more aggressive tumors (7). Research studies have suggested a functional role for podoplanin in the stromal microenvironment of tumors. For example, it has been reported that podoplanin expression in cancer-associated fibroblasts (CAFs) is positively associated with a stromal environment that promotes cancer progression (8,9).