Recombinant Mouse LAG-3 Fc Chimera Protein, CF

• Reactivity: Mu
• Applications: Bioactivity
• Format: Carrier-Free

Recombinant Mouse LAG-3 Fc Chimera Protein, CF Summary

• Details of Functionality: Measured by its ability to induce TNF-alpha secretion by JAWSII mouse immature dendritic cells. The ED₅₀ for this effect is 0.4-2.4 µg/mL.
• Source: Mouse myeloma cell line, NS0-derived mouse LAG-3 protein
  

  Mouse LAG-3 (Gly24-Leu442) Accession # Q61790	IEGRMDP	Mouse IgG2A (Glu98-Lys330)
  N-terminus		C-terminus

• Accession #: Q61790
• N-terminal Sequence: Gly24
• Structure / Form: Disulfide-linked homodimer
• Protein/Peptide Type: Recombinant Proteins
• Gene: Lag3
• Purity: >95%, by SDS-PAGE visualized with Silver Staining and quantitative densitometry by Coomassie® Blue Staining.
• Endotoxin Note: <0.10 EU per 1 μg of the protein by the LAL method.

Applications/Dilutions

• Dilutions:
  • Bioactivity
• Theoretical MW: 72.4 kDa (monomer).
  Disclaimer note: The observed molecular weight of the protein may vary from the listed predicted molecular weight due to post translational modifications, post translation cleavages, relative charges, and other experimental factors.
• SDS-PAGE: 85-100 kDa, reducing conditions

Packaging, Storage & Formulations

• Storage:
  • 12 months from date of receipt, ≤ -20 °C as supplied.
  • 1 month, 2 to 8 °C under sterile conditions after reconstitution.
  • 3 months, ≤ -20 °C under sterile conditions after reconstitution.
• Buffer: Lyophilized from a 0.2 μm filtered solution in PBS.
• Purity: >95%, by SDS-PAGE visualized with Silver Staining and quantitative densitometry by Coomassie® Blue Staining.
• Reconstitution Instructions: Reconstitute at 250 μg/mL in PBS. Reconstitute 30 minutes prior to use with minimal agitation.

Notes

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

Alternate Names for Recombinant Mouse LAG-3 Fc Chimera Protein, CF

• 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 70 kDa type I transmembrane protein that is a member of the immunoglobulin superfamily (IgSF) (1, 2). LAG-3 shares approximately 20% amino acid 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). Mouse LAG-3 cDNA encodes 521 amino acids (aa) that include a 22 aa signal sequence, a 420 aa extracellular domain (ECD) with four Ig-like domains, a  transmembrane region and a highly charged cytoplasmic region. Within the ECD, mouse LAG-3 shares 86% aa sequence identity with rat LAG-3, and 65-69% with human, porcine, and bovine LAG-3. 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⁺ T_reg 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 a homodimerized sLAG-3/Ig fusion protein 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/Ig 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).

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.

Publications for LAG-3 (3328-L3)(1)

Publication using 3328-L3

• MM Soldevilla, S Hervas, H Villanueva, T Lozano, O Rabal, J Oyarzabal, JJ Lasarte, M Bendandi, S Inoges, A López-Díaz, F Pastor Identification of LAG3 high affinity aptamers by HT-SELEX and Conserved Motif Accumulation (CMA) PLoS ONE, 2017-09-21;12(9):e0185169. 2017-09-21 [PMID: 28934318] (Bioassay, N/A)

Bioinformatics

• Gene Symbol: Lag3
• Uniprot:
  • Q61790()