Objective To detect the anti-citrullinated
alpha-enolase peptide 1 (CEP-1) antibody in
rheumatoid arthritis (RA).
Methods One hundred and twenty-nine
patients with RA were enrolled randomly. Thirty-one
patients with primary Sj?gren's
syndrome (pSS), 32
patients with
systemic lupus erythematosus (SLE), 32
patients with
osteoarthritis (OA), and 106 healthy controls (HC) were include into this study. Anti-CEP-1 antibody was detected by
enzyme-linked immunosorbent assay (
ELISA). The correlations between
serum anti-CEP-1 antibody and clinical features,
disease activities,
laboratory tests or Sharp scores of RA
patients were evaluated.
Mann-Whitney U test and χ2 test were used for
statistical analysis. Results ①Anti-CEP-1
antibodies were positive in 64.3%(83/129) of RA
patients, 22.6%(7/32) of pSS
patients, 12.5%(4/32) of SLE
patients, none of OA
patients (0/32) or healthy controls. The positivity of anti-CEP-1 antibody was significantly higher than those in pSS ( χ2=17.7), SLE ( χ2=25.7), OA ( χ2=42.5), and healthy controls ( χ2=102.6) (P<0.01, respectively). The
specificity of anti-CEP-1 antibody in RA was 94.5%. ②In
patients without anti-citrullinated
protein/
peptide autoantibodies (ACPA),
rheumatoid factor (RF) or the
patients without ACPA and RF, the positive rate of anti-CEP-1 antibody was 30.3%(10/33), 41.9%(18/43) and 22.7%(5/22), respectively. ③Compared with
patients without anti-CEP-1
antibodies,
patients with anti-CEP-1 anti-bodies had higher rates of
joint deformity,
bone erosion and high
disease activities (P<0.05, respectively). ④ Higher rate of
interstitial lung disease (ILD) was found in RA
patients with anti-CEP-1 antibody (19.3% vs 4.3%, χ2=5.494, P<0.05). ⑤The
patients with anti-CEP-1 anti-body had higher rates of elevated
erythrocyte sedimentation rate (ESR) ( χ2=6.543) and decreased
serum albumin ( χ2=6.59), compared to
patients without anti-CEP-1 antibody (P<0.05, respectively). Conclusion Anti-CEP-1 antibody has high
sensitivity and specificity for RA
diagnosis. Combination of anti-CEP-1 antibody with other RA
antibodies might improve the
early diagnosis of RA. Anti-CEP-1 antibody is significantly associated with
joint damage,
disease activity and pulmonary interstitial
fibrosis.