Product DetailsRecommended AssayReferencesDescriptionThe 53-6.7 antibody monoclonal antibody specifically binds to the 38 kDaαand 34 kDaα " chains of the CD8 differentiation antigen (Ly-2 or Lyt-2) of all mouse strains tested. The CD8αandα " chains (CD8a) form heterodimers with the CD8βchain (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 CD8αβheterodimer (theα " chain is absent). Subsets ofγδTCR-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 CD8αandα " chains arise from alternatively spliced messengers of a singleCD8agene. The longerαform associates with p56 [lck] via a CXCP motif in its cytoplasmic domain, which it shares with CD4, but not with CD8b. The truncatedα " 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-reaact with CD8α - andα "-like polypeptides on subsets of thymic and peripheral lymphocytes in the Egyptian toad,Bufo regularis . Format × FormatPEExcitation SourceBlue 488 nm,Green 532 nm,Yellow/Green 561 nmExcitation Max496nmEmission Max578nmR-phycoerythrin (PE) is an accessory photosynthetic pigment found in red algae. It exists in vitro as a 240-kDa protein with 23 phycoerythrobilin chromophores per molecule. This makes PE one of the brightest fluorochromes for flow cytometry applications, but its photobleaching properties make it unsuitable for fluorescence microscopy.Other Formats→APCAPC-Cy™7APC-H7APC-R700Alexa Fluor® 488Alexa Fluor® 647Alexa Fluor® 700BB515BB700BUV395BUV496BUV563BUV615BUV661BUV737BUV805BV421BV480BV510BV605BV650BV711BV750BV786BiotinFITCNA/LEPE-CF594PE-Cy™5PE-Cy™7Pacific Blue™PerCPPerCP-Cy™5.5PurifiedR718V450V500Suggested Companion ProductsStain Buffer (BSA) RUO 500mLCat No: 554657 BD Cytofix/Cytoperm™ Fixation/Permeablization Kit RUO 250TestsCat No: 554714 Stain Buffer (FBS) RUO 500mLCat No: 554656 PE Rat IgG2a, κ Isotype Control RUO 0.1mgCat No: 553930 PE Rat Anti-Mouse CD8a 53-6.7RUO 0.2mgCat No: 553033 Resources & ToolsSpectrum ViewerPanel DesignerSpectrumViewerDownload TDSRegulatory Document WebsitePreparation and StorageStore 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 R-PE under optimum conditions, and unconjugated antibody and free PE were removed.Product NoticesSince applications vary, each investigator should titrate the reagent to obtain optimal results.An isotype control should be used at the same concentration as the antibody of interest.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.For fluorochrome spectra and suitable instrument settings, please refer to our Multicolor Flow Cytometry web page at www.bdbiosciences.com/colors.Please refer to www.bdbiosciences.com/pharmingen/protocols for technical protocols.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.View referenceFujiura 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.View referenceHathcock KS. T cell depletion by cytotoxic elimination. Curr Protoc Immunol. 1991; 1:3.4.1-3.4.3.View referenceJaneway 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.View referenceKruisbeek AM, Shevach EM. Proliferative assays for T cell function. Curr Protoc Immunol. 2004; 3:3.12.1-3.12.14.View referenceLedbetter JA, Herzenberg LA. Xenogeneic monoclonal antibodies to mouse lymphoid differentiation antigens. Immunol Rev. 1979; 47:63-90.View referenceLedbetter 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.View referenceLedbetter 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.View referenceLeFrancois L. Extrathymic differentiation of intraepithelial lymphocytes: generation of a separate and unequal T-cell repertoire. Immunol Today. 1991; 12(12):436-438.View referenceLeishman 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.View referenceMacDonald 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.View referenceMitnacht 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.View referenceMurosaki S, Yoshikai Y, Ishida A, et al. Failure of T cell receptor V beta negative selection in murine intestinal intra-epithelial lymphocytes. Int Immunol. 1991; 3(10):1005-1013.View referenceNakayama 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.View referenceNegm 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.View referenceO"Rourke AM, Mescher MF. The roles of CD8 in cytotoxic T lymphocyte function. Immunol Today. 1993; 14(4):183-188.View referenceRocha B, Vassalli P, Guy-Grand D. The extrathymic T-cell development pathway. Immunol Today. 1992; 14(3):140-141.View referenceSydora BC, Brossay L, Hagenbaugh A, Kronenberg M, Cheroutre H. TAP-independent selection of CD8+ intestinal intraepithelial lymphocytes. J Immunol. 1996; 156(11):4209-4216.View referenceTraver D, Akashi K, Manz M, et al. Development of CD8alpha-positive dendritic cells from a common myeloid progenitor. Science. 2000; 290(5499):2152-2154.View referencevan Ewijk W, van Soest PL, van den Engh GJ. 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