Zeta’s rabbit recombinant monoclonal IVD antibody for IHC recognizes Cytokeratin 7, an intermediate filament protein (IFP) of 55kDa. The Cytokeratin 7 antibody is highly specific to cytokeratin 7 and shows no cross-reaction with other IFPs. Cytokeratin 7 is a basic cytokeratin, which is found in most glandular and transitional epithelia but not in the stratified squamous epithelia. Keratin 7 is expressed in the epithelial cells of ovary, lung, and breast but not of colon, prostate, or gastrointestinal tract. This monoclonal antibody is highly useful in distinguishing ovarian carcinomas (keratin 7+) from colon carcinomas (keratin 7-).