The interplay between citrullination and HLA-DRB1 polymorphism in shaping peptide binding hierarchies in rheumatoid arthritis
Yi Tian Ting, Jan Petersen, Sri H Ramarathinam, Stephen W Scally, Khai L Loh, Ranjeny Thomas, Anish Suri, Daniel G Baker, Anthony W Purcell, Hugh H Reid, Jamie Rossjohn
JOURNAL OF BIOLOGICAL CHEMISTRY | AMER SOC BIOCHEMISTRY MOLECULAR BIOLOGY INC | Published : 2018
The HLA-DRB1 locus is strongly associated with rheumatoid arthritis (RA) susceptibility, whereupon citrullinated self-peptides bind to HLA-DR molecules bearing the shared epitope (SE) amino acid motif. However, the differing propensity for citrullinated/non-citrullinated self-peptides to bind given HLA-DR allomorphs remains unclear. Here, we used a fluorescence polarization assay to determine a hierarchy of binding affinities of 34 self-peptides implicated in RA against three HLA-DRB1 allomorphs (HLA-DRB1*04:01/*04:04/*04:05) each possessing the SE motif. For all three HLA-DRB1 allomorphs, we observed a strong correlation between binding affinity and citrullination at P4 of the bound peptide..View full abstract
Supported by National Health and Medical Research Council research fellowships.Supported by an ARC Laureate Fellowship.