Monoclonal Antibody to Cytokeratin (45,46,56.4 kD) (Clone MNF116)

Background
Cytokeratins make up the largest family among the cytoplasmic intermediate filaments (IF) proteins and are expressed specifically in epithelial cells in a cell-specific manner. Cytokeratins include more than 20 unique gene products (termed K1-K20) that are divided into type I (K9-K20) and type II (K1-K8). This antibody recognizes cytokeratin polypeptides ranging from 40 through 58 KD and corresponding to cytokeratins 5, 6, 8, 17 and 19. Cytokeratin 5 is a type-II cytokeratin, specifically expressed in the basal layer of the epidermis with family member cytokeratin14. The pathological role of cytokeratin 5 has been identified in epidermolysis bullosa simplex, epidermolysis bullosa simplex Dowling-Meara type (DM-EBS) and Dowling-Degos disease. It maps to 12q12-q13 region of human chromosome. Cytokeratin 6 is a type-II cytokeratin, existing in six different isomeric forms which associate with cytokeratin 16 and/or cytokeratin 17. Mutations in this gene have been associated with pachyonychia congenita. It maps to 12q12-q13 region of human chromosome.Cytokeratin 8 is the only type-II cytokeratin occurring in many simple epithelial cells, and can also be synthesized in certain non-epithelial cells.Together with cytokeratin 19, it helps to link the contractile apparatus to dystrophin at the costameres of striated muscle. Mutations in this gene have been linked to liver cirrhosis. It maps to 12q13 region of human chromosome. Cytokeratin 17 is a type I cytokeratin, expressed in abundance in nail bed, hair follicle, sebaceous glands, and other epidermal appendages. Mutations in this gene lead to Jackson-Lawler type pachyonychia congenita and steatocystoma multiplex. It maps to 17q12-q21 region of human chromosome. Cytokeratin 19 is a type I intermediate filament protein that is expressed in stratified and simple-type epithelia. It is unique in that it has a very short 13-amino acid tail domain. It possesses assembly properties and it may impart unique properties to the basal cells expressing it in skin epithelia. It maps to the 17q21.2 region oh human chromosome and has a molecular weight of 44,098 Da.

Antigen
BALB/C mice were immunized with crude extract of splenic cells from a nude mouse engrafted with MCF-7 cells.

Application Notes
We suggest an incubation period of 30 minutes at room temperature. However, depending upon the fixation conditions and the staining system employed, optimal incubation should be determined by the user. Enzymatic predigestion of paraffin embedded tissues is recommended prior to the immunostaining. Specificity: This antibody recognizes cytokeratin polypeptides ranging from 40 through 58kD, corresponding to cytokeratins 5, 6, 8,17 and 19. It shows a broad pattern of reactivity with human epithelial tissues from simple glandular epithelia to stratified squamous epithelia, like epidermis, mammary gland ducts and tracheal epithelium. Cellular Localization: Cytoplasmic.

Genebank Info (Protein)
NP_571584

Reference
1. Gatter et al. J Clin Pathol 35: 1253, 1982.
2. Gosh et al. Br J Haematol 61: 21, 1985.
3. Norton et al. Histopathol 11: 487, 1987.