Additionally, while AP by SE-expressing HLA-DR molecules has been long postulated to be a disease-susceptibility mechanism in RA, only minor overlaps were found among the repertoires of peptides eluted from different SE-expressing HLA-DR molecules (encoded by either DRB1*01:01; DRB1*04:01, or DRB1*10:01). Here, HLA-DRB1 is linked to rheumatoid arthritis.