cFluor^® BYG781 Anti-Human CD21 (LT21)

The mouse monoclonal antibody clone LT21 binds to an extracellular epitope of human CD21, a 145 kDa type I transmembrane glycoprotein also known as complement receptor 2 (CR2), C3d receptor (C3dR), and EBV receptor. CD21 is expressed on mature B lymphocytes, follicular dendritic cells, a subset of T lymphocytes, and some epithelial cells, but is absent on immature B cells. CD21 functions as a receptor for complement fragments C3d, C3dg, and iC3b, which remain covalently attached to complement-activating surfaces and antigens. On the B cell surface, CD21 associates with CD19, CD81, and Leu-13 to form a large co-receptor signaling complex that amplifies B cell receptor activation in response to complement-opsonized antigens. CD21 also serves as the obligate receptor for Epstein-Barr virus (EBV), mediating viral binding and entry into B lymphocytes via interaction with the viral glycoprotein gp350/220. Additional roles for CD21 include uptake and retention of immune complexes, survival of memory B cells, and maintenance of the humoral response to T-dependent antigens. Clone LT21 has been validated for flow cytometric analysis of human peripheral blood leukocytes and has been reported to cross-react with canine and porcine CD21. PRODUCT DETAILSClone: LT21Specificity: CD21Reactivity: Human, Dog, PigFormat: cFluor® BYG781Isotype: Mouse IgG1Tested Dilution: 5 µl/TestApplication: Flow CytometryStorage: 2-8°C protected from light. Do not freezeFormulation: Phosphate-buffered saline, pH 7.2, containing 0.09% sodium azide and 0.2% BSA (BSA Country of Origin USA)Data Sheets: TDS | SDS RECOMMENDED USAGEEach lot of this antibody is quality control tested using flow cytometric analysis. For flow cytometric staining, the suggested use of this reagent is 5 μL per 1 million cells in a staining volume of 100 μL. If whole blood is analyzed, then use 5 μL per 100 μL. It is recommended that users titrate the antibody to obtain the optimal result for their specific application. Please briefly centrifuge the reagent vial before use. Use appropriate personal protective equipment per the product safety data sheet when using this product. REFERENCES Weis, J.J. et al. 1984. Proc. Natl. Acad. Sci. USA. 81: 881–885. Matsumoto, A.K. et al. 1993. J. Exp. Med. 178: 1407–1417. Fearon, D.T. and Carter, R.H. 1995. Annu. Rev. Immunol. 13: 127–149. For research use only. Not intended for use in diagnostic procedures. cFluor® BYG781 is a tandem dye made with R-PE. Caution – Tandem dyes may show changes in their emission spectra with prolonged exposure to light or fixatives.