Myosin, Smooth Muscle Heavy Chain

Myosins are a large family of motor proteins found in eukaryotic tissues. They are responsible for actin-based motility. Smooth Muscle Myosin, Heavy Chain is a cytoplasmic structural protein that is a major component of the contractile apparatus of the smooth muscle cells, as well as a myoepithelium-associated protein.

SMM-H24 is a mouse monoclonal antibody to Smooth Muscle Myosin, Heavy Chain that reacts with human visceral and vascular smooth muscle cells. The antibody also reacts with human myoepithelial cells. It is very helpful in distinguishing between benign sclerosing breast lesions and infiltrating Carcinomas in difficult cases, since it strongly stains the myoepithelial layer in the benign lesions while it is negative in the infiltrating Carcinomas.

Smooth Muscle Myosin, Heavy Chain 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.

1. Nan Ping Wang, Bing C Wan, et al. Appl Immunohistochem. 5(3):141-151
2. Werling RW, et al. Am J Surg Pathol. 2003;Jan;27(1):82-90
3. Ago– SN, et al. Appl Immunohistochem Mol Morphol. 2001;Jun;9(2):164-169

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.