CD63

CD63 is a human gene. The protein encoded by this gene is a member of the transmembrane-4 superfamily, also known as the tetraspanin family, and mediates signal-transduction events that play a role in the regulation of cell development, activation, growth and motility. This encoded protein is a cell-surface glycoprotein that is known to complex with integrins. It may function as a blood-platelet activation marker. Deficiency of this protein is associated with Hermansky-Pudlak Syndrome. This gene has been associated with tumor progression. CD63 is a good marker for flow-cytometric quantification of in vitro-activated basophils for diagnosis of IgEmediated allergy. The test is commonly designated as a basophil activation test.

Anti-CD63 reacts with a 53 kDa protein. The antigen was originally designated as a lysosomal membrane protein characterized as an activation-dependent platelet surface antigen. In fact, the CD63 antigen has a diverse distribution on the surface and in the cytoplasm of many cell types including lymphoid, myeloid and endothelial cells and Melanoma. It is weakly expressed in granulocytes, B and T-cells. It has been quite useful in identifying Malignant Melanoma. CD63 is thought to be associated with the early stages of Melanoma tumor progression (in regulation of motility and adhesion of Melanoma cells).

CD63 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. Berditchevski F, et al. J. Biol. Chem. 1997;272(5):2595-8
2. Radford KJ, et al. Biochem. Biophys. Res. Commun. 1996;222(1):13-18
3. Hotta H, et al. Jpn. J. Cancer Res. 1990;80(12):1186-91

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.