LAG-3 Antibody (333210) [Alexa Fluor® 405]

• Applications: WB
• Clone: 333210
• Clonality: Monoclonal
• Host: Mouse
• Conjugate: Alexa Fluor 405

LAG-3 Antibody (333210) [Alexa Fluor® 405] Summary

• Immunogen: Mouse myeloma cell line NS0-derived recombinant human LAG-3
  Leu23-Leu450
  Accession # P18627
• Specificity: Detects human LAG‑3 in direct ELISAs and Western blots. In direct ELISAs and Western blots, no cross‑reactivity with recombinant mouse LAG-3 is observed.
• Isotype: IgG2a
• Clonality: Monoclonal
• Host: Mouse
• Purity Statement: Protein A or G purified

Packaging, Storage & Formulations

• Storage: Protect from light. Do not freeze. 12 months from date of receipt, 2 to 8 °C as supplied
• Buffer: Supplied 0.2mg/ml in 1X PBS with RDF1 and 0.09% Sodium Azide

Notes

This product is produced by and ships from R&D Systems, Inc., a Bio-Techne brand.

Background

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. The extracellular domain of human and mouse LAG-3 share 69% amino acid sequence identity. 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. 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⁺ T_Reg 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.

Limitations

This product is for research use only and is not approved for use in humans or in clinical diagnosis. Primary Antibodies are guaranteed for 1 year from date of receipt.