Anti-Claudin-2 (8H11), monoclonal

The claudin family is composed of 23 integral membrane proteins, and their expression, which varies among tissue types, may determine both the strength and properties of the epithelial barrier. Alteration in claudin protein expression pattern is associated with several types of cancer . Claudin-2 is expressed primarily in the proximal tubule of the normal mammalian kidney, where it regulates transepithelial ion (e.g., Na+, Cl-) reabsorption . Increased expression of Claudin-2 has been reported in some cancer cell lines , including A549 lung adenocarcinoma cells, where its nuclear distribution was positively associated with enhanced proliferation . Protein Function: Forms paracellular channels: polymerizes in tight junction strands with cation- and water-selective channels through the strands, conveying epithelial permeability in a process known as paracellular tight junction permeability (PubMed:20460438, PubMed:36008380). In intestinal epithelium, allows for sodium and water fluxes from the peritoneal side to the lumen of the intestine to regulate nutrient absorption and clear enteric pathogens as part of mucosal immune response (By similarity). In kidney, allows passive sodium and calcium reabsorption across proximal tubules from the lumen back to the bloodstream (By similarity). In the hepatobiliary tract, allows paracellular water and cation fluxes in the hepatic perivenous areas and biliary epithelium to generate bile flow and maintain osmotic gradients (By similarity) [The Uniprot Consortium]