Quantitative affinity measurement of small molecule ligand binding to major histocompatibility complex class-I-related protein 1 MR1.

ABSTRACT: The Major Histocompatibility Complex class I-related protein 1 (MR1) presents small molecule metabolites, drugs, and drug-like molecules that are recognized by MR1-reactive T cells. While we have an understanding of how antigens bind to MR1 and upregulate MR1 cell surface expression, a quantitative, cell-free, assessment of MR1 ligand-binding affinity was lacking. Here, we developed a fluorescence polarization-based assay in which fluorescent MR1 ligand was loaded into MR1 protein in vitro and competitively displaced by candidate ligands over a range of concentrations. Using this assay, ligand affinity for MR1 could be differentiated as strong (IC₅₀ < 1 μM), moderate (1 μM < IC₅₀ < 100 μM), and weak (IC₅₀ > 100 μM). We demonstrated a clear correlation betwe

SUBMITTER: Wang CJH 

PROVIDER: S-EPMC9764189 | biostudies-literature | 2022 Dec

REPOSITORIES: biostudies-literature