Anti-Claudin-1 CLDN1 Antibody

Claudin1 (CLDN1), a member of the claudin family, is an integral membrane protein and a component of tight junction strands. Tight junctions are specialized regions of cell to cell contact consisting of networking strands that act as a molecular gasket for preventing the leakage of ions, water, etc., between cells. They are abundant in luminal epithelial sheets where they maintain epithelial cell polarity. Different tissues exhibit different Claudin composition and CLDN1 expression is often cell type and tissue dependent. Loss of function mutations result in neonatal ichthyosis-sclerosing cholangitis syndrome. CLDN1 and CLDN2 were found to be overexpressed in colonal cancer tissues and may be useful as tumor markers and targets for the treatment of colorectal cancer. Characterization of Claudins expression in human tumors can be an additional diagnostic tool. Recent studies show that CLDN1 has gastric tumor suppressive activity and is a direct transcriptional target of RUNX3. Along with SCARB1, LDL-R, and the tetraspanin superfamily member CD81, CLDN1 has been reported to be an entry factor for the Hepatitis C virus.

Anti-CLDN1 antibody was raised against a peptide corresponding to 20 amino acids near the carboxy terminus of human CLDN1. The immunogen is located within the last 50 amino acids of CLDN1.

Claudins function as major constituents of the tight junction complexes that regulate the permeability of epithelia. While some claudin family members play essential roles in the formation of impermeable barriers, others mediate the permeability to ions and small molecules. Often, several claudin family members are coexpressed and interact with each other, and this determines the overall permeability. CLDN1 is required to prevent the paracellular diffusion of small molecules through tight junctions in the epidermis and is required for the normal barrier function of the skin. Required for normal water homeostasis and to prevent excessive water loss through the skin, probably via an indirect effect on the expression levels of other proteins, since CLDN1 itself seems to be dispensable for water barrier formation in keratinocyte tight junctions (PubMed:23407391) .

CLDN1 antibody can be stored at 4°C for three months and -20°C, stable for up to one year. Avoid repeated freeze-thaw cycles. Antibodies should not be exposed to prolonged high temperatures.