LAG-3 Antibody [PerCP (Peridinin-chlorophyll Protein Complex)]

• Applications: Flow
• Clonality: Polyclonal
• Host: Goat
• Conjugate: PerCP (Peridinin-chlorophyll Protein Complex)

LAG-3 Antibody [PerCP (Peridinin-chlorophyll Protein Complex)] 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, less than 1% cross-reactivity with recombinant mouse LAG-3 is observed.
• Source: N/A
• Isotype: IgG
• Clonality: Polyclonal
• Host: Goat
• Gene: LAG3
• Purity Statement: Antigen Affinity-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 in a saline solution containing BSA and Sodium Azide.
• Preservative: 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. 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⁺ 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.

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.

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.

Bioinformatics

• Gene Symbol: LAG3