Human LAG‑3 Antibody

  • Specificity
    Detects human LAG-3 in direct ELISAs and Western blots. In direct ELISAs and Western blots, less than 1% cross-reactivity with recombinant mouse LAG-3 is observed.
  • Source
    Polyclonal Goat IgG
  • Purification
    Antigen Affinity-purified
  • Immunogen
    Mouse myeloma cell line NS0-derived recombinant human LAG-3
    Accession # P18627
  • Formulation
    Lyophilized from a 0.2 μm filtered solution in PBS with Trehalose. *Small pack size (SP) is supplied as a 0.2 µm filtered solution in PBS.
  • Label
  • Western Blot
    0.1 µg/mL
    Recombinant Human LAG‑3 Fc Chimera (Catalog # 2319-L3)
  • Flow Cytometry
    0.25 µg/106 cells
    See below
Please Note: Optimal dilutions should be determined by each laboratory for each application. General Protocols are available in the Technical Information section on our website.
Data Examples
Detection of LAG‑3 in CD3+ Human PBMCs by Flow Cytometry. Human peripheral blood mononuclear cells (PBMCs) either (A) untreated or (B) treated with 1 ug/mL PHA for 5 days were stained with Goat Anti-Human LAG-3 Antigen Affinity-purified Polyclonal Antibody (Catalog # AF2319) followed by Allophycocyanin-conjugated Anti-Goat IgG Secondary Antibody (Catalog # F0108) and Mouse Anti-Human CD3e PE-conjugated Monoclonal Antibody (Catalog # FAB100P). Quadrant markers were set based on control antibody staining (Catalog # AB-108-C).
Preparation and Storage
  • Reconstitution
    Reconstitute at 0.2 mg/mL in sterile PBS.
  • Shipping
    The product is shipped at ambient temperature. Upon receipt, store it immediately at the temperature recommended below. *Small pack size (SP) is shipped with polar packs. Upon receipt, store it immediately at -20 to -70 °C
  • Stability & Storage
    Use a manual defrost freezer and avoid repeated freeze-thaw cycles.
    • 12 months from date of receipt, -20 to -70 °C as supplied.
    • 1 month, 2 to 8 °C under sterile conditions after reconstitution.
    • 6 months, -20 to -70 °C under sterile conditions after reconstitution.
Background: LAG-3
LAG-3 (Lymphocyte activation gene-3), also known as CD223, is a member of the immunoglobulin superfamily (IgSF). The mature LAG-3 protein is a 496 amino acid (aa) membrane protein with a 421 aa extracellular region which contains four IgSF domains, a 21 aa transmembrane region and a 54 aa cytoplasmic region. LAG-3 and CD4 molecules share < 20% aa sequence homology but have a similar structure (1, 2). Both molecules bind to MHC class II. LAG-3 binds to MHC class II with higher affinity compared to CD4. Both LAG-3 and CD4 genes are located on the distal part of the short arm of chromosome 12. LAG-3 is an activation-induced molecule, expressed on activated T cells and NK cells, but not on resting T cells. Studies using LAG-3 -/- mice have shown significant delay of T cell apoptosis following antigen stimulation and increased size of memory T cells pool following infection (3, 4). It also has been reported that anti-LAG-3 antibodies up-regulate T cell activation by blocking interaction of LAG-3 and MHC class II. The study has demonstrated that LAG-3 is selectively expressed on activated CD4+CD25+ TReg cells and plays a role in their suppressive activity (5). This evidence indicated, unlike the interaction of CD4 with MHC class II that plays a positive role in T cell activation, LAG-3 binds to MHC class II and negatively regulates T cell activation through LAG-3 signaling. On the other hand, studies have shown that binding of LAG-3 to MHC class II molecules on antigen presenting cells induce maturation of dendritic cells and cytokine secretion by monocytes through MHC class II signal transduction (6). Taken together, LAG-3 may have two major functions, it negatively regulates T cells activation through LAG-3 signaling and stimulates antigen presenting cells which express MHC class II.
  • References:
    1. Triebel, F. et al. (1990) J. Exp. Med. 171:1393.
    2. Baixeras, E. et al. (1992) J. Exp. Med 176:327.
    3. Workman, C.J. and D.A. Vignali (2003) Eur. J. Immunol. 33:970.
    4. Workman, C.J. et al. (2004) J. Immunol. 172:5450.
    5. Huang, C.T. et al. (2004) Immunity 21:503.
    6. Andreae, S. et al. (2003) Blood 102:2130.
  • Long Name:
    Lymphocyte-activation Gene 3
  • Entrez Gene IDs:
    3902(Human); 16768(Mouse); 297596(Rat)
  • Alternate Names:
    CD223; CD223; CD223 antigen; FDC; LAG-3; lymphocyte activation gene 3 protein; lymphocyte-activation gene 3; Protein FDC
Related Research Areas

R&D Systems personnel manually curate a database that contains references using R&D Systems products. The data collected includes not only links to publications in PubMed, but also provides information about sample types, species, and experimental conditions.

Showing Results 1 - 1 of 1

  1. Responsiveness of HIV-specific CD4 T cells to PD-1 blockade.
    Authors: Porichis F, Kwon DS, Zupkosky J, Tighe DP, McMullen A, Brockman MA, Pavlik DF, Rodriguez-Garcia M, Pereyra F, Freeman GJ, Kavanagh DG, Kaufmann DE
    Blood, 2011;118(4):965-74.
    Species: Human
    Sample Type: Whole Cells
    Application: Flow Cytometry,


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