CD79a

CD79a is non-covalently associated with membrane-bound immunoglobulins on B-cells to constitute the B-cell Ag receptor. CD79a first appears at pre B-cell stage and persists until the plasma-cell stage, where it is found as an intracellular component. CD79a is found in the majority of Acute Leukemias of precursor B-cell type, in B-cell lines, B-cell Lymphomas, and in some Myelomas.

CD79a is a B-cell marker that is generally used to complement CD20. This antibody will stain many of the same Lymphomas as CD20, but also stains more B-precursor Lymphoid Leukemias than CD20. CD79a also stains more cases of Plasma-cell Myeloma and occasionally some types of endothelial cells as well. CD79a will stain many cases of Acute Promyelocytic Leukemia (FAB-M3), but only rarely stains other types of Myeloid Leukemia.

CD79a 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. Van Nosel CJM, et al. J Immunol. 1991;146:3881-3888
2. Van Nosel CJM, et al. J Exp Med. 1992;175:1511-1519
3. Mason DY, et al. Eur J Immun. 1992;22:2753-2756

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.