Comparison of commercially available cytokeratin antibodies in normal and neoplastic adult epithelial and non-epithelial tissues.

Five commercially available cytokeratin antibodies (lu-5, AE1/AE3, CAM 5.2, MFN116 and anti-cytokeratin 18) were used to stain a wide range of normal and neoplastic epithelial and non-epithelial tissues to assess their potential value in diagnostic histopathology. All five showed good specificity, with some cross-reactivity in smooth muscle cells. The wider reactivity of AE1/AE3, lu-5, and MFN 116, which includes cytokeratins 8,18 (Moll's catalogue) expressed in simple epithelia and their tumours, as well as cytokeratins expressed in complex stratified squamous epithelia, permits identification of a wider range of epithelial derived tumours. This wider spectrum of reactivity may allow these antibodies to be used in a diagnostic panel for the identification of poorly differentiated tumours.