Skip to main content Skip to navigation
PE-Cy™5 Rat Anti-Mouse CD8a
Product Details
Down Arrow Up Arrow

BD Pharmingen™
Cd8a; CD8 alpha chain; Ly-2; Lyt2; Lyt-2; Ly-35; Ly-B
Mouse (QC Testing)
Rat LOU, also known as Louvain, LOU/C, LOU/M IgG2a, κ
Mouse Spleen Cells or Thymocyte Membranes
Flow cytometry (Routinely Tested)
0.2 mg/ml
Aqueous buffered solution containing ≤0.09% sodium azide.

Preparation And Storage

Store undiluted at 4°C and protected from prolonged exposure to light. Do not freeze. The monoclonal antibody was purified from tissue culture supernatant or ascites by affinity chromatography. The antibody was conjugated with PE-Cy5 (formerly known as BD Cy-Chrome™) under optimum conditions, and unconjugated antibody and free PE-Cy5 were removed.

Product Notices

  1. Since applications vary, each investigator should titrate the reagent to obtain optimal results.
  2. An isotype control should be used at the same concentration as the antibody of interest.
  3. Caution: Sodium azide yields highly toxic hydrazoic acid under acidic conditions. Dilute azide compounds in running water before discarding to avoid accumulation of potentially explosive deposits in plumbing.
  4. Please observe the following precautions: Absorption of visible light can significantly alter the energy transfer occurring in any tandem fluorochrome conjugate; therefore, we recommend that special precautions be taken (such as wrapping vials, tubes, or racks in aluminum foil) to prevent exposure of conjugated reagents, including cells stained with those reagents, to room illumination.
  5. For fluorochrome spectra and suitable instrument settings, please refer to our Multicolor Flow Cytometry web page at
  6. PE-Cy5 is optimized for use with a single argon ion laser emitting 488-nm light. Because of the broad absorption spectrum of the PE-Cy5 tandem fluorochrome, extra care must be taken when using dual-laser cytometers which may directly excite both PE and Cy5™.
  7. PE-Cy5 is a tandem fluorochrome composed of R-phycoerythrin (PE), which is excited by the 488 nm light of an Argon ion laser and serves as an energy donor, coupled to the cyanine dye Cy5, which acts as an energy acceptor and fluoresces at 670 nm. BD Biosciences Pharmingen has maximized the fluorochrome energy transfer in PE-Cy5, thus maximizing its fluorescence emission intensity, minimizing residual emission from PE, and minimizing lot-to-lot variation.
  8. PE-Cy5 tandem fluorochromes have been reported to bind some classes of human macrophages and granulocytes via Fc receptors, and PE has been reported to bind to mouse B lymphocytes via Fc receptors. Preincubation of mouse leukocytes with Mouse BD Fc Block™ purified anti-mouse CD16/CD32 mAb 2.4G2 can reduce the non-specific binding of PE-Cy5-conjugated reagents to mouse B cells. However, PE-Cy5 conjugated reagents should not be used to stain splenocytes of SJL, NOD, and MRL mice as B lymphocytes and/or other leukocytes have been reported to non-specifically stain regardless of the use of Mouse BD Fc Block™ (the CD72c complex has been implicated for PE-Cy5 binding in these strains). Reagents conjugated to PE, PerCP, PerCP-Cy5.5, APC, and APC-Cy7 tandem fluorochrome can be used on leukocytes from these mouse strains.
  9. Cy is a trademark of GE Healthcare.
  10. Please refer to for technical protocols.
561094 Rev. 3
Antibody Details
Down Arrow Up Arrow

The 53-6.7 monoclonal antibody specifically binds to the 38 kDa α and 34 kDa α' chains of the CD8 differentiation antigen (Ly-2 or Lyt-2) of all mouse strains tested. The CD8 α and α' chains (CD8a) form heterodimers with the CD8 β chain (CD8b, Ly-3, or Lyt-3) on the surface of most thymocytes. A subpopulation of mature T lymphocytes (i.e., MHC class I-restricted T cells, including most T suppressor/cytotoxic cells) expresses almost exclusively the CD8 αβ heterodimer. Subsets of γδ TCR-bearing T cells, intestinal intrapithelial lymphocytes, and dendritic cells express CD8a without CD8b. It has been suggested that the expression of the CD8a/CD8b heterodimer is restricted to T lymphocytes which matured in the thymus or in an extrathymic environment that had been influenced by thymus-initiated neuroendocrine signals. CD8 is an antigen coreceptor on the T-cell surface which interacts with MHC class I molecules on antigen-presenting cells or epithelial cells. It participates in T-cell activation through its association with the T-cell receptor complex and protein tyrosine kinase lck (p56 [lck]). The CD8 α and α' chains arise from alternatively spliced messengers of a single CD8a gene. The longer α form associates with p56 [lck] via a CXCP motif in its cytoplasmic domain, which it shares with CD4, but not with CD8b. The truncated α' chain is unable to associate with p56 [lck], and it may function to attenuate the CD8-mediated costimulatory signal during intrathymic T-cell maturation.  In vivo and in vitro treatment with 53-6.7 mAb has reportedly been effective at depleting CD8+ peripheral T lymphocytes. The 53-6.7 antibody has also been reported to cross-react with CD8 α- and α'-like polypeptides on subsets of thymic and peripheral lymphocytes in the Egyptian toad, Bufo regularis.

561094 Rev. 3
Format Details
Down Arrow Up Arrow
PE-Cy5 dye is a part of the BD PE family of dyes. This tandem fluorochrome is comprised of a R-Phycoerythrin (PE) donor that has excitation maxima (Ex Max) of 496 nm and 566 nm and an acceptor dye, Cy™5, with an emission maximum (Em Max) at 670-nm. PE designed to be excited by the Blue (488-nm), Green (532-nm) and yellow-green (561-nm) lasers and detected using an optical filter centered near 670-nm (e.g., a 670/20-nm bandpass filter). The donor dye can be excited by the Blue (488-nm), Green (532-nm) and yellow-green (561-nm) lasers and the acceptor dye can be excited by the Red (627-640-nm) laser resulting in cross-laser excitation and fluorescence spillover. Please ensure that your instrument’s configurations (lasers and optical filters) are appropriate for this dye.
Yellow-Green 488 nm, 532 nm, 561 nm
496 nm, 566 nm
670 nm
561094 Rev.3
Citations & References
Down Arrow Up Arrow

Development References (24)

  1. Bierer BE, Sleckman BP, Ratnofsky SE, Burakoff SJ. The biologic roles of CD2, CD4, and CD8 in T-cell activation. Annu Rev Immunol. 1989; 7:579-599. (Biology). View Reference
  2. Doucet M, Soussi N, Crain-Denoyelle AM, Gendron MC, Sanchez P. R-phycoerythrin-cyanine 5 tandem discerns CD72 polymorphism. Immunogenetics. 2001; 53(4):307-314. (Methodology: Flow cytometry). View Reference
  3. Fujiura Y, Kawaguchi M, Kondo Y, et al. Development of CD8 alpha alpha+ intestinal intraepithelial T cells in beta 2-microglobulin- and/or TAP1-deficient mice. J Immunol. 1996; 156(8):2710-2715. (Biology). View Reference
  4. Janeway CA Jr. The T cell receptor as a multicomponent signalling machine: CD4/CD8 coreceptors and CD45 in T cell activation. Annu Rev Immunol. 1992; 10:645-674. (Biology). View Reference
  5. Kruisbeek AM, Shevach EM. Proliferative assays for T cell function. Curr Protoc Immunol. 2004; 3:3.12.1-3.12.14. (Methodology: Depletion). View Reference
  6. LeFrancois L. Extrathymic differentiation of intraepithelial lymphocytes: generation of a separate and unequal T-cell repertoire. Immunol Today. 1991; 12(12):436-438. (Biology). View Reference
  7. Ledbetter JA, Herzenberg LA. Xenogeneic monoclonal antibodies to mouse lymphoid differentiation antigens. Immunol Rev. 1979; 47:63-90. (Biology). View Reference
  8. Ledbetter JA, Rouse RV, Micklem HS, Herzenberg LA. T cell subsets defined by expression of Lyt-1,2,3 and Thy-1 antigens. Two-parameter immunofluorescence and cytotoxicity analysis with monoclonal antibodies modifies current views. J Exp Med. 1980; 152(2):280-295. (Biology). View Reference
  9. Ledbetter JA, Seaman WE, Tsu TT, Herzenberg LA. Lyt-2 and lyt-3 antigens are on two different polypeptide subunits linked by disulfide bonds. Relationship of subunits to T cell cytolytic activity. J Exp Med. 1981; 153(6):1503-1516. (Biology). View Reference
  10. Leishman AJ, Naidenko OV, Attinger A, et al. T cell responses modulated through interaction between CD8alphaalpha and the nonclassical MHC class I molecule, TL. Science. 2001; 294(5548):1848-1849. (Biology). View Reference
  11. MacDonald HR, Schreyer M, Howe RC, Bron C. Selective expression of CD8 alpha (Ly-2) subunit on activated thymic gamma/delta cells. Eur J Immunol. 1990; 20(4):927-930. (Biology). View Reference
  12. Mitnacht R, Bischof A, Torres-Nagel N, Hunig T. Opposite CD4/CD8 lineage decisions of CD4+8+ mouse and rat thymocytes to equivalent triggering signals: correlation with thymic expression of a truncated CD8 alpha chain in mice but not rats. J Immunol. 1998; 160(2):700-707. (Biology). View Reference
  13. Nakayama K, Nakayama K, Negishi I, et al. Requirement for CD8 beta chain in positive selection of CD8-lineage T cells. Science. 1994; 263(5150):1131-1133. (Biology). View Reference
  14. Negm HI, Mansour MH, Saad AH, Abdel Halim RS. Structural characterization of an Lyt-2/3 homolog expressed on Bufo regularis lymphocytes. Comp Biochem Physiol B Biochem Mol Biol. 1996; 113(1):79-87. (Biology). View Reference
  15. O'Rourke AM, Mescher MF. The roles of CD8 in cytotoxic T lymphocyte function. Immunol Today. 1993; 14(4):183-188. (Biology). View Reference
  16. Rocha B, Vassalli P, Guy-Grand D. The extrathymic T-cell development pathway. Immunol Today. 1992; 14(3):140-141. (Biology). View Reference
  17. Sydora BC, Brossay L, Hagenbaugh A, Kronenberg M, Cheroutre H. TAP-independent selection of CD8+ intestinal intraepithelial lymphocytes. J Immunol. 1996; 156(11):4209-4216. (Biology). View Reference
  18. Takizawa F, Kinet JP, Adamczewski M. Binding of phycoerythrin and its conjugates to murine low affinity receptors for immunoglobulin G. J Immunol Methods. 1993; 162(2):269-272. (Biology). View Reference
  19. Traver D, Akashi K, Manz M, et al. Development of CD8alpha-positive dendritic cells from a common myeloid progenitor. Science. 2000; 290(5499):2152-2154. (Biology). View Reference
  20. Zamoyska R, Derham P, Gorman SD, et al. Inability of CD8 alpha' polypeptides to associate with p56lck correlates with impaired function in vitro and lack of expression in vivo. Nature. 1989; 342(6247):278-281. (Biology). View Reference
  21. Zamoyska R, Vollmer AC, Sizer KC, Liaw CW, Parnes JR. Two Lyt-2 polypeptides arise from a single gene by alternative splicing patterns of mRNA. Cell. 1985; 43(1):153-163. (Biology). View Reference
  22. Zamoyska R. The CD8 coreceptor revisited: one chain good, two chains better. Immunity. 1994; 1(4):243-246. (Biology). View Reference
  23. van Ewijk W, van Soest PL, van den Engh GJ. Fluorescence analysis and anatomic distribution of mouse T lymphocyte subsets defined by monoclonal antibodies to the antigens Thy-1, Lyt-1, Lyt-2, and T-200. J Immunol. 1981; 127(6):2594-2604. (Biology). View Reference
  24. van Vugt MJ, van den Herik-Oudijk IE, van de Winkle JG. Binding of PE-CY5 conjugates to the human high-affinity receptor for IgG (CD64). Blood. 1996; 88(6):2358-2361. (Biology). View Reference
View All (24) View Less
561094 Rev. 3

Please refer to Support Documents for Quality Certificates

Global - Refer to manufacturer's instructions for use and related User Manuals and Technical data sheets before using this products as described

Comparisons, where applicable, are made against older BD Technology, manual methods or are general performance claims.  Comparisons are not made against non-BD technologies, unless otherwise noted.

For Research Use Only. Not for use in diagnostic or therapeutic procedures.