Cytokeratin 18 (Biotin)

Cytokeratins (CK) are intermediate filaments of epithelial cells, both in keratinizing tissue (ie., skin) and non keratinizing cells (ie. mesothelial cells). Although not a traditional marker for endothelial cells, cytokeratins have also been found in some microvascular endothelial cells. Atleast 20 different cytokeratins (CK) in the molecular range of 40-70kD and isoelectric points of 5-8.5 can be identified using two dimensional gel electrophoresis. Biochemically, most members of the CK family fall into one of two classes, type I (acidic polypeptides) and type II (basic polypeptides). At least one member of the acidic family and one member of the basic family is expressed in all epithelial cells. Monoclonal antibodies to cytokeratin proteins can be useful markers for tumor identification and classification. Cytokeratin 18 is an acidic keratin which is found primarily in non squamous epithelia and is present in a majority of adenocarcinomas and ductal carcinomas but not in squamous cell carcinomas. Cytokeratin 18 exists in combination with Cytokeratin 8, a basic keratin. Hepatocellular carcinomas have been reportedly defined by the use of antibodies that recognize only Cytokeratins 8 and 18. Applications: Suitable for use in Immunofluorescence, Western Blot, Immunoprecipitation, Immunohistochemistry (paraffin-embedded sections) and Immunocytochemistry. Other applications not tested. Recommended Dilution: Western Blot: 1:500. Predicted molecular weight 47kD. Immunohistochemistry (paraffin-embedded sections): 1:500. Immunocytochemistry: 1:500. Immunoprecipitation: 1:500. Optimal dilutions to be determined by the researcher. Storage and Stability: May be stored at 4 degrees C for short-term only. For long-term storage and to avoid repeated freezing and thawing, aliquot Store at -20 degrees C. Aliquots are stable for at least 6 months at -20 degrees C. For maximum recovery of product, centrifuge the original vial after thawing and prior to removing the cap. Further dilutions can be made in assay buffer.