Description:
Cytokeratins are intermediate filament cytoskeletal proteins
essential to development and differentiation of epithelial cells.
Approximately twenty different cytokeratins have been identified and
are classified and numbered according to molecular weight and
isoelectric points. In general, most low molecular weight
cytokeratins (40-54 kDa) are distributed in nonsquamous epithelium,
Moll’s catalog numbers 7-8 and/or 17-20. High molecular weight
cytokeratins (48-67 kDa) are found in the squamous epithelium,
Moll’s catalog numbers 1-6 and/or 9-16. CK20 (Clone KS20.8) is to
identify epithelial cells in normal and neoplastic tissues using
immunohistochemical methods. CK20 is valuable as a histodiagnostic
tool for the subtyping of various carcinomas, including
adenocarcinomas.1 It is an aid for a more precise classification of
many epithelial tumors whose differential diagnosis is otherwise
difficult. This
antibody reacts with the 46 kDa cytokeratin intermediate filament
protein as indicated by immunoblotting of cytokeratin-enriched
cytoskeletal preparations isolated from villi of duodenal mucosa.
The cytokeratin was initially described as “protein IT” but has
recently been designated cytokeratin 201 supplementing the
previously described number of the cytokeratin polypeptides. CK 20
is less acidic than the other type 1 cytokeratins and is of
particular interest because of its restricted range of expression.
Primary Antibody
Name: Cytokeratin 20 Antibody |
Clone: KS20.8, Mouse anti-Human |
Supplier: Dako |
Catalog Number: M7019 |
Dilution: 1:100 using IHC-TekTM Antibody Diluent (Cat# IW-1000 or IW-1001) to reduce background and unspecific staining and serum blocking step is NOT needed. |
Incubation Time/Temp: 60 minutes/room temperature |
Device: IHC-TekTM Epitope Retrieval Steamer Set (Cat# IW-1102) |
Buffer/pH value: IHC-TekTM Epitope Retrieval Solution (Cat# IW-1100) |
Heat/Cool Temperature: 95-100 ºC/room temperature |
Heat/Cool Time: 20 minutes/20 minutes |
Standard Method: ABC Method or LSAB Method |
Enhanced Method: Polymeric Methods |
Reagent: DAB |
Incubation Time/Temperature: 1-3 minutes/room temperature |
Reagent: Mayer's Hematoxylin |
Staining Time: 30 seconds |
Staining Pattern: Cytoplasmic |
Images: Search image |
Tissue Type: Skin |
Fixation: Formalin fixed paraffin sections. |
Positive Control: Intestinal epithelium, gastric foveolar epithelium, skin. |
Negative Control: Omit primary antibody, isotype control or absorption control |
Blocking: 2-5% normal serum to reduce unspecific background staining; 0.5-3% H2O2 to block endogenous peroxidase activity; avidin/biotin to block endogenous biotin activity if necessary |
Not tested on frozen sections. |
References: