LAG3-MHCII Immune Checkpoint Biochemical Assay

Lymphocyte activation gene-3 (LAG-3), also known as CD223 or FDC protein, is a novel immune checkpoint receptor expressed on CD4+, CD8+Tcells and natural killer (NK) cells and plays an important role in regulating the immune response against tumor antigens and autoantigens. The binding of LAG-3 to its functional ligand, the MHCII complex, results in cytokine production, activated T cells proliferation, and inhibition of TCR signaling. Therapeutics designed to exploit the LAG-3/MHCII binding have shown encouraging results as a potential treatment for many human diseases, including autoimmunity and cancer.

Target Overview


To provide a screening assay for identifying small and large molecule LAG-3 and MHCII binding interaction blockage inhibitors, with the goal of eventually studying immune responses to aid in the discovery of novel immunotherapies to combat cancer.




Human LAG3, human MHCII


LAG3: Lymphocyte activation gene 3 protein, CD223, FDC

MHCII: HLA-DRA, MHC class II antigen DRA, HLA class II histocompatibility antigen, DR alpha chain

Scientific Information

P18627 (
P01903 (

Assay Properties


Binding interaction between LAG3 and MHCII



Reference Compound IC50s
Compounds IC50 (nM)
Ieramilimab 2.8

Screening Location

Malvern, PA, USA

Further Information

More information can be found on our website Immune Checkpoint Assays

Reference compound inhibition of LAG3-MHCII binding interaction

Reference compound inhibition of LAG3-MHCII binding interaction