Antibodies against β-fibrin synthetic peptides: a study of their association with the immunogenetic background and disease course of rheumatoid arthritis patients.

Preliminary studies have shown the potential application for the diagnosis of Rheumatoid Arthritis (RA) patients with a severe disease course of an epitopic domain of β-fibrin. The aim of the present work was the analysis of the presence of antibodies against several β-fibrin synthetic peptides in relation to the immunogenetic background and disease course in a clinically well-defined RA patient cohort. Our results indicated that positive patients against anti-β-fibrin synthetic peptides have a higher percentage of HLA-DRB1 shared epitope (SE) than negative patients. We also observed that the presence of SE alleles was significantly associated with a higher level of anti-[Cit376]βfib(365–383) antibodies. When analyzing the effect of different SE alleles, we found a significant positive association between carriers of QRRAA allele and [Cit376]βfib(365–383) (Odds ratio 3.77; CI95%: 1.41–10.08). These results suggest that the anti-β-fibrin status is associated with the immunogenetic background of RA patients.