Cytokeratin 8/35βH11

Cytokeratin 8 belongs to the Type B (basic) subfamily of high molecular-weight keratins and exists in combination with cytokeratin 18. Cytokeratin 8 is primarily found in the non-squamous epithelia and is present in the majority of Adenocarcinomas and Ductal Carcinomas. It is absent in Squamous Cell Carcinomas. Hepatocellular Carcinomas are de€ ned by the use of antibodies that recognize only cytokeratin polypeptides 8 and 18.

Anti-Cytokeratin 8/35βH11 stains most Non-Squamous Epithelial tumors; Squamous tumors are negative for this antibody as a rule. This antibody stains Adenocarcinomas of the breast, ovary, gastrointestinal tract, thyroid, pancreas, bile duct, and salivary glands. This antibody does not react with skeletal muscle or nerve cells.

Anti-Cytokeratin 8/35βH11 is a mouse monoclonal antibody derived from cell culture supernatant that is concentrated, dialyzed, filter sterilized and diluted in buffer pH 7.5, containing BSA and sodium azide as a preservative.

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1. Cut and mount 3-4 micron formalin-fixed paraffin-embedded tissues on positive charged slides.
2. Air dry for 2 hours at 58° C.
3. Deparaffinize, dehydrate and rehydrate tissues.
4. Subject tissues to heat epitope retrieval using a suitable retrieval solution such as ImmunoDNA Retriever with Citrate (BSB 0020-BSB 0023) or EDTA (BSB 0030-BSB 0033).
5. Any of three heating methods may be used:
   • Electric Pressure Cooker
     Place standoff rack at base of pressure cooker. Add 1-2 inches of distilled water to the pressure cooker and turn heat to high, and incubate for 15 minutes. Open and immediately transfer slides to room temperature.
   • Water Bath Method
     Place tissues/slides in a pre-warmed staining dish or coplin jar containing the ImmunoDNA Retriever with Citrate or EDTA in a water bath set at 95°-99° C. Incubate for 30-60 minutes.
   • Conventional Steamer Method
     Place tissues/slides in a pre-warmed staining dish or coplin jar containing the ImmunoDNA Retriever with Citrate or EDTA in a Steamer, cover and steam for 30-60 minutes.
6. After heat treatment, transfer slides in ImmunoDNA Retriever with Citrate or EDTA to room temperature and let stand for 15-20 minutes.
7. Wash slides with IHC wash buffer or DI water.
8. Continue IHC staining protocol.