CK5/6

Cytokeratin 5/6 antibody reacts strongly with cytokeratins 5 and 6 and weakly with cytokeratin 4. The antibody does not cross-react with cytokeratins 1, 7, 8, 10, 13, 14, 18 and 19. It labels mesothelial cell origin including mesothelioma, and epithelial basal cells in prostate and tonsil. Cytokeratin 5 is expressed in various epithelia and mesothelial cells, while cytokeratin 6 is expressed by proliferating squamous epithelium. This antibody exhibits a cytoplasmic staining pattern and may be used to aid in the identification of squamous cell carcinoma and in distinguishing malignant mesothelioma from lung adenocarcinomas. This antibody identifies breast basal and myoepithelial cells as well as prostate basal cells (1).

Recommended Controls

Criteria for acceptable staining is a cytoplasmic staining pattern. The recommended controls to include are tonsil and normal prostate. Tonsil: The squamous epithelial cells should show a moderate to strong diffuse cytoplasmic staining reaction. The staining should be seen in all cell layers in the epithelial surface. Prostate: The basal cells should show a weak to moderate cytoplasmic staining reaction with no or only focal staining of the secretory cells.

Expected staining pattern

Mesothelioma

Disclaimer

These methods are intended as a guide only. Laboratories that wish to implement these methods should perform internal validation/verification prior to use. The RCPAQAP does not make any claim or warranty for the accuracy or performance of these methods.