LAG-3 Protein, Human (HEK293, Llama Fc)

LAG-3 (lymphocyte activating gene 3) protein is an inhibitory receptor on antigen-activated T cells and is critical for immune regulation. LAG-3 binds to FGL1 and transmits inhibitory signals that negatively affect CD8(+) and CD4(+) T cell proliferation, activation, and effector functions. LAG-3 Protein, Human (HEK293, Llama Fc) is the recombinant human-derived LAG-3 protein, expressed by HEK293, with C-Llama Fc labeled tag.

LAG-3 (Lymphocyte activation gene 3) protein, an inhibitory receptor present on antigen-activated T-cells, plays a crucial role in immune regulation. Upon binding to its major ligand, FGL1, LAG-3 delivers inhibitory signals that negatively regulate the proliferation, activation, effector function, and homeostasis of both CD8(+) and CD4(+) T-cells. Acting in synergy with PDCD1/PD-1, LAG-3 may inhibit antigen-specific T-cell activation, particularly following T-cell receptor (TCR) engagement where it associates with CD3-TCR in the immunological synapse. Beyond its role in T-cell inhibition, LAG-3 is constitutively expressed on a subset of regulatory T-cells (Tregs), contributing to their suppressive function and mediating immune tolerance. Additionally, LAG-3 negatively regulates plasmacytoid dendritic cell (pDCs) activation and, intriguingly, interacts with MHC class II (MHC-II), potentially acting as both a ligand for MHC-II on antigen-presenting cells (APC) and a promoter of APC activation/maturation, thereby influencing Th1 immune response.

Human

HEK293

C-Llama Fc

P18627 (L23-L450)

3902

Extracellular Domain

Approximately 90 kDa,based on SDS-PAGE under reducing conditions,due to the glycosylation.

Greater than 95% as determined by reducing SDS-PAGE.

Lyophilized powder.

Lyophilized from 0.22 μm filtered solution of Tris with Glycine, Arginine and NaCl, pH7.5 with trehalose as protectant.
Note: For SPR assay, please replace the buffer. Primary amine components (e.g., Tris, imidazole) can affect protein-coupled chips.

<1 EU/μg, determined by LAL method.

It is not recommended to reconstitute to a concentration less than 100 μg/mL in ddH₂O. For long term storage it is recommended to add a carrier protein (0.1% BSA, 5% HSA, 10% FBS or 5% Trehalose).

Stored at -20°C for 2 years from date of receipt. After reconstitution, it is stable at 4°C for 1 week or -20°C for longer (with carrier protein). It is recommended to freeze aliquots at -20°C or -80°C for extended storage.

Room temperature in continental US; may vary elsewhere.