Twenty human keratins are resolved with two-dimensional gel electrophoresis into acidic (pI <5.7) and basic (pI >6.0) subfamilies. This antibody cocktail recognizes acidic (Type I or LMW) and basic (Type II or HMW) cytokeratins, which 67 kDa (CK1) ; 64 kDa (CK3) ; 59 kDa (CK4) ; 58 kDa (CK5) ; 56 kDa (CK6) ; 52 kDa (CK8) ; 56.5 kDa (CK10) ; 50 kDa (CK14) ; 50 kDa (CK15) ; 48 kDa (CK16) ; 40 kDa (CK19) . Many studies have shown the usefulness of keratins as markers in cancer research and tumor diagnosis. It is a broad spectrum anti pan-cytokeratin antibody cocktail, which differentiates epithelial tumors from non-epithelial tumors e.g. squamous vs. adenocarcinoma of the lung, liver carcinoma, breast cancer, and esophageal cancer. It may be useful to characterize the source of various neoplasms and to study the distribution of cytokeratin containing cells in epithelia during normal development and during the development of epithelial neoplasms. This antibody stains cytokeratins present in normal and abnormal human tissues and has high sensitivity in the recognition of epithelial cells and carcinomas. Primary antibodies are available purified, or with a selection of fluorescent CF® Dyes and other labels. CF® Dyes offer exceptional brightness and photostability. Note: Conjugates of blue fluorescent dyes like CF®405S and CF®405M are not recommended for detecting low abundance targets, because blue dyes have lower fluorescence and can give higher non-specific background than other dye colors.