Fig. 1

a Concentrations of antibodies against viral citrullinated peptides derived from Epstein-Barr-virus derived protein (VCP1) in controls, pre-symptomatic individuals and patients with rheumatoid arthritis (RA). Grey line indicates the mean of the concentrations; ***p < 0.001. b Concentrations of anti-VCP2 antibodies in controls, pre-symptomatic individuals and patients with RA. Grey line indicates the mean of the concentrations; ***p < 0.001. c Concentrations of antibodies against histone 4-derived citrullinated peptides (HCP1) in controls, pre-symptomatic individuals and patients with RA. Grey line indicates the mean of the concentrations; ***p < 0.001. d Concentrations of anti-HCP2 antibodies in controls, pre-symptomatic individuals and patients with RA. Grey line indicates the mean of the concentrations; ***p < 0.001. AU arbitrary units