Twenty human keratins are resolved with two-dimensional gel electrophoresis into acidic (pI 6.0) subfamilies. This antibody recognizes acidic (Type I or LMW) and basic (Type II or HMW) cytokeratins, including 59 kDa (CK4) ; 58 kDa (CK5) ; 56 kDa (CK6) ; 52 kDa (CK8) ; 56.5 kDa (CK10) ; 53 kDa (CK13) and 45 kDa (CK18) . This is a broad-spectrum antibody, which has been reported to differentiate epithelial tumors from non-epithelial tumors. Many studies have shown the usefulness of keratins as markers in cancer research and tumor diagnosis.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.