Biolegend, 561214, Biotinylated Recombinant Human CD223 (LAG-3)-Fc Chimera (carrier-free), 25μg

Initially documented in the 1990, lymphocyte activation gene 3 (LAG-3, CD223) is an inhibitory co-receptor of the type-1 immunoglobulin family with a molecular mass of 50 kD. LAG-3 exhibits four extracellular immunoglobulin-like domains named D1 to D4, a transmembrane region and an intracellular region. Except the proline-rich loop located on D1, LAG-3 is structurally similar to the CD4 co-receptor. LAG-3 selectively interacts with the major histocompatibility complex class II (MHC II) of antigen presenting cells (APCs) and tumor cells which activate the inhibitory pathway and eventually lead to dysfunction of T-cells. LAG-3 receptors and their ligands are expressed in the tumor microenvironment and form a complex organization for cell-communication. LAG-3 receptors are present on almost all T-lymphocytes (activated CD4+ T-cells, CD8+ T-cells, FOXP3+ regulatory T-cells and Naïve T-cells), NK cells and dendritic cells (DCs). Dendritic cells express both LAG-3 receptors and their ligands and LAG-3 induced signaling promotes their maturation. LAG-3 acts synergistically with PD-1 and/or other immunoregulatory genes to prevent autoimmunity in mice. The infiltrated LAG3+ lymphocytes are associated with overall survival of TNBC and HER2+ breast cancer patients, in addition, peripheral blood LAG3+ immunotype strongly corelates with treatment responses, survival, progression-free survival in melanoma. Current existing clinical therapeutic agents targeting LAG-3 can be classified into three different groups; the LAG-3 fusion protein, the LAG-3 monoclonal antibody and the LAG-3 involving bispecific antibody. A novel combinatorial FDA approved immunotherapy uses LAG-3 blocking agent together with nivolumab (anti-PD-1 agent) for metastatic melanoma’ which may suggest future prospects of LAG-3 targeted therapies for cancer patients.
25μg
Source: Biotinylated human CD223 (LAG-3)-Fc Chimera, amino acids Leu23-Leu450 (Accession # P18627), with a C-terminal human IgG1-Fc tag and -Avi tag, was expressed in 293E cells.
Molecular Mass: The 707 amino acid recombinant protein has a predicted molecular mass of approximately 77.09 kD. The DTT-reduced and non-reduced protein migrate at approximately 80 kD and 200 kD respectively in SDS-PAGE. The predicted N-terminal amino acid is Leu.
Purity: > 95%, as determined by Coomassie stained SDS-PAGE
Formulation: 0.22 µm filtered protein solution is in 2 mM CHAPS, PBS pH 7.2
Endotoxin Level: Less than 0.1 EU per μg of protein as determined by the LAL method
Concentration: 25 µg size is bottled at 200 µg/mL. 100 µg size and larger sizes are lot-specific and bottled at the concentration indicated on the vial. To obtain lot-specific concentration and expiration, please enter the lot number in our Certificate of Analysis online tool.
Storage & Handling: Unopened vial can be stored between 2°C and 8°C for up to 2 weeks, at - 20°C for up to six months, or at -70°C or colder until the expiration date. For maximum results, quick spin vial prior to opening. The protein can be aliquoted and stored at -20°C or colder. Stock solutions can also be prepared at 50 - 100 μg/mL in appropriate sterile buffer, carrier protein such as 0.2 - 1% BSA or HSA can be added when preparing the stock solution. Aliquots can be stored between 2°C and 8°C for up to one week and stored at -20°C or colder for up to 3 months. Avoid repeated freeze/thaw cycles.
Activity: Biotinylated Recombinant Human CD223 (LAG-3)-Fc Chimera induces TNFα secretion in JAWSII cells in a dose-dependent manner. ED50 of this effect is 0.08 – 0.8 µg/mL.
Application: Bioassay
Application Notes: BioLegend carrier-free recombinant proteins provided in liquid format are shipped on blue-ice. Our comparison testing data indicates that when handled and stored as recommended, the liquid format has equal or better stability and shelf-life compared to commercially available lyophilized proteins after reconstitution. Our liquid proteins are validated in-house to maintain activity after shipping on blue ice and are backed by our 100% satisfaction guarantee. If you have any concerns, contact us at [email protected].
Structure: Monomer
Distribution: T-lymphocytes, NK cells, and dendritic cells (DCs)
Function: T-cell dysfunction, dendritic cell maturation, role in autoimmunity
Interaction: All T-lymphocytes (activated CD4+ T-cells, CD8+ T-cells, FOXP3+ regulatory T-cells and Naïve T-cells), NK cells and dendritic cells (DCs), antigen presenting cells (APCs) and tumor cells
Ligand/Receptor: MHC II of antigen presenting cells (APCs) and tumor cells
Bioactivity: Biotinylated Recombinant Human CD223 (LAG-3)-Fc Chimera induces TNFα secretion in JAWSII cells in a dose-dependent manner. ED50 of this effect is 0.08 – 0.8 µg/mL.
Cell Type: Dendritic cells, NK cells, T cells, Tregs
Biology Area: Immunology, Inhibitory Molecules
Molecular Family: CD Molecules, Immune Checkpoint Receptors
Antigen References: Triebel F, et al. 1990. J Exp Med. 171:1393-405. 2. Chocarro L, et al. 2021. Int. J. Mol. Sci. 17:5282. Gaikwad S, et al. 2022. Semin Cancer Biol. 86:137-150. Avice MN, et al. 1999. J Immunol. 162:2748-53. Lecocq Q, et al. 2020. Int J Mol Sci. 22:75. Mair MJ, et al. 2021. J Neurooncol. 152:533. Datar I, et al. 2019. Clin Cancer Res. 25:4663-4673. Zeng H, et al. 2020. J Immunother Cancer. 8:e000651. Andreae S, et al. 2003. Blood. 102:2130-7. Okazaki T, et al. 2011. J Exp Med. 208:395-407. Guoming H, et al. 2023. Front Oncol. 12:986903. Shen R, et al. 2021. Sci Transl. Med. 13:eabf5107.
Gene ID: 3902
UniProt: View information about CD223 on UniProt.org
Regulatory Status: RUO
Other Names: Lymphocyte activation gene 3 protein, LAG-3, Secretedlymphocyte activation gene 3 protein, sLAG3, CD223