Invitrogen™ Claudin 4 Monoclonal Antibody (3E2C1)

Description

Reactivity has been confirmed with human, rat ileum homogenates, and canine MDCK cell lysates by western blotting and immunofluorescence. Reactivity has also been confirmed with formalin-fixed, paraffin-embedded (FFPE) human normal colon and colon cancer tissues by immunohistochemistry. For best results in immunohistochemistry with formalin-fixed, paraffin-embedded (FFPE) tissues, heat induced epitope retrieval (HIER) with citrate buffer, pH 6.0, is required prior to staining. This antibody reacts specifically with the ~ 22 kDa Claudin-4 protein and does not cross-react with the protein at 55 kDa.

Claudin-4 belongs to the 20-member family of claudins, transmembrane cellular adhesion proteins localized at epithelial and endothelial tight junctions. Claudins demonstrate distinct, tissue-specific expression patterns, and are essential components of tight junction charge-specific channels that regulate paracellular ion flux. Claudin-4 is a component of tight junction strands and may play a role in internal organ development and function during pre- and postnatal life. The overexpression of Claudin-4 has been shown to decrease paracellular electrical conductance due to a selective decrease in Na+ permeability, with no significant decrease in Cl^- permeability. In ovarian carcinoma cells, Claudin-3 and Claudin-4 exhibit upregulation at both mRNA and protein levels. Claudin-4 is also overexpressed in pancreatic cancer tissues and cell lines, and in other epithelial cancers. The Claudin-4 gene is deleted in Williams-Beuren syndrome, a neurodevelopmental disorder affecting multiple systems.