Sequential high-content profiling of the IgG-autoantibody repertoire reveals novel antigens in rheumatoid arthritis.
BACKGROUND
The aim was to identify novel diagnostic autoantibody candidates for rheumatoid arthritis (RA) by comprehensive screening for autoreactivity.


METHOD
We incubated 5892 recombinant proteins coupled to fluorescent beads, with patients' sera for the detection of IgG-autoantibodies in three independent patient cohorts: A (n = 72 patients with established RA); B/B- (n = 116 patients with early RA (B) and n = 51 CCP-negative patients with early RA from B (B-)); and C (n = 184 patients with early seronegative RA), in comparison to matched healthy controls. Intersects of significantly increased autoantibodies as determined by the Mann-Whitney test were sought.


RESULT
Screening of 5892 antigens in RA cohorts A and B, or the seronegative cohorts B- and C revealed intersects of 23 and 13 significantly increased autoantibodies, respectively. Reactivity to three antigens was increased in all cohorts tested: N-acetylglucosamine-1-phosphate transferase, gamma subunit (GNPTG), heterogeneous nuclear ribonucleoprotein A1-like 2 (HNRNPA1), and insulin-like growth factor binding protein 2 (IGFBP2).


CONCLUSIONS
Comprehensive sequential screening for autoantibodies reveals novel candidates for diagnostic markers in both seropositive and seronegative RA and suggests new fields of research into the pathogenesis of RA.
['Vordenbäumen|Stefan|S|', 'Lueking|Angelika|A|', 'Budde|Petra|P|', 'Zucht|Hans-Dieter|HD|', 'Goehler|Heike|H|', 'Brinks|Ralph|R|', 'Fischer-Betz|Rebecca|R|', 'Richter|Jutta|J|', 'Bleck|Ellen|E|', 'Detert|Jacqueline|J|', 'Langer|Hans-Eckhard|HE|', 'Sörgel|Anne|A|', 'Burmester|Gerd-Rüdiger|GR|', 'Schulz-Knappe|Peter|P|', 'Schneider|Matthias|M|']
D000328:Adult D000368:Aged D001172:Arthritis, Rheumatoid D001323:Autoantibodies D001324:Autoantigens D015415:Biomarkers D004797:Enzyme-Linked Immunosorbent Assay D005260:Female D006801:Humans D007074:Immunoglobulin G D008297:Male D008875:Middle Aged
Rheumatoid arthritis Autoantibody Biomarker