Although both disease groups demonstrated a heterogeneous immunoreactivity profile against the autoantigen panel, the SSc/SRC subjects showed two enriched clusters with one featuring elevated levels of autoantibodies against Ro52 and/or Ro60 and another with high levels of immunoreactivity against the RNA polymerase complex.
Anti-Ro-52 and anti-Scl-70 had increased values for predicting ILD in SSc patients, while anti-Ro-52 had increased values for predicting PAH in SSc patients.
Excluding anti-Ro52, 113 (89.3%) SSc patients were positive for at least one autoAb: anti-Topoisomerase I (anti-Topo) I abs in 54 (41.2%), anti-centromere proteins (anti-CENP) in 37 (28.2%, all reactive with centromere protein-A (CENPA) and centromere protein B (CENPB)), anti-RNA polymerase III(RP11) in 19 (14.5%), anti-RNA polymerase III(RP155) in 13 (9.9%), anti-fibrillarin in 4 (3.1%), anti-Ku in 6 (4.6%), anti-nucleolus-organizing region (anti-NOR90) in 8 (6.1%), anti-PM-Scl100 in 2 (1.5%), and anti-PM-Scl75 in 4 (3.1%).