LAG-3 Antibody (2561B) [Alexa Fluor™ Plus 594]

• Reactivity: Pm-Cm
• Clone: 2561B
• Clonality: Monoclonal
• Host: Rabbit
• Conjugate: Alexa Fluor Plus 594

LAG-3 Antibody (2561B) [Alexa Fluor™ Plus 594] Summary

• Specificity: Detects cynomolgus monkey LAG-3 in direct ELISAs.
• Isotype: IgG
• Clonality: Monoclonal
• Host: Rabbit

Packaging, Storage & Formulations

• Storage: Protect from light. Do not freeze. 12 months from date of receipt, 2 to 8 °C as supplied
• Buffer: Supplied 0.2 mg/mL in a saline solution containing BSA and Sodium Azide.

Notes

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

Alternate Names for LAG-3 Antibody (2561B) [Alexa Fluor™ Plus 594]

• CD223 antigen
• CD223
• LAG3
• LAG-3
• lymphocyte activating 3
• lymphocyte activation gene 3 protein
• lymphocyte-activation gene 3
• Secreted lymphocyte activation gene 3 protein
• sLAG-3

Background

LAG-3 (Lymphocyte activation gene-3), designated CD223, is a type I transmembrane protein that is a member of the immunoglobulin superfamily (IgSF) (1, 2). LAG ‑ 3 shares approximately 20% amino acid (aa) sequence homology with CD4, but has similar structure and binds to MHC class II with higher affinity, providing negative regulation of T cell receptor signaling (1, 2). The mature cynomolgus LAG-3 includes an extracellular domain (ECD) with four Ig-like domains, a transmembrane region and a highly charged cytoplasmic region. Within the ECD, cynomolgus LAG-3 shares 92%, 69% and 68% aa sequence identity with human, mouse and rat LAG-3, respectively. LAG-3 is expressed on activated CD4+ and CD8⁺ T cells, NK cells, and plasmacytoid dendritic cells (pDC), but not on resting T cells (1-3). LAG-3 on activated CD4⁺CD25⁺ Treg cells plays a role in their suppressive activity (4). LAG-3 limits the expansion of activated T cells and pDC in response to selected stimuli (3-5). A soluble 54 kDa form, sLAG-3, can be shed by metalloproteinases ADAM10 and TACE/ADAM17 (6, 7). While monomeric sLAG-3 itself may be inactive, shedding allows for normal T cell activation by removing negative regulation (7). Binding of sLAG-3 to MHC class II molecules induces maturation of immature DC, and secretion of cytokines such as IFN-gamma and TNF-alpha by type 1 cytotoxic CD8⁺ T cells and NK cells (8, 9). sLAG-3 has been used as a potential adjuvant to stimulate a cytotoxic anti-cancer immune response (9, 10). In mice, deletion of LAG-3 and another negative regulator, PD-1, facilitates anti-cancer response but also blocks self-tolerance and increases susceptibility to autoimmune diseases (11, 12). In humans, antibody-mediated down‑regulation of LAG-3 and PD-1 allows more effective control of chronic malaria, while in NOD (non‑obese diabetic) mice, deletion of LAG-3 alone accelerates diabetes (12-14). In addition, LAG-3 is an immune checkpoint protein that modulates T-cell activation and homeostasis and is a promising target for cancer immunotherapies (15, 16).

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. et al. (2004) J. Immunol. 172:5450.
4. Huang, C.T. et al. (2004) Immunity 21:503.
5. Workman, C.J. et al. (2009) J. Immunol. 182:1885.
6. Li, N. et al. (2004) J. Immunol. 173:6806.
7. Li, N. et al. (2007) EMBO J. 26:494.
8. Andreae, S. et al. (2003) Blood 102:2130.
9. Brignone, C. et al. (2007) J. Immunol. 179:4202.
10. Brignone, C. et al. (2010) J. Transl. Med. 8:71.
11. Woo, S.R. et al. (2011) Cancer Res. 72:917.
12. Okazaki, T. et al. (2011) J. Exp. Med. 208:395.
13. Bettini, M. et al. (2011) J. Immunol. 187:3493.
14. Butler, N.S. et al. (2012) Nat. Immunol. 13:188.
15. Durham N.M. et al. (2014) PLoS One. 9:e109080.
16. Deng W.W. et al. (2016) Oncoimmunology. 5:e1239005

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.