Fig. 7: The autoantibodies against cit-IGF2BP1 were detected in RA Serum and SF.

A, B Autoantibodies against cit-IGF2BP1 were detected by immunodot blot in RA serum (n = 15), HC serum (n = 15), RA SF (n = 12), and HC SF (n = 6) (1:5000 dilution). Representative images were shown. Noncit-IGF2BP1, BSA, and cit-BSA were used as control antigens. C Autoantibodies against cit-IGF2BP1 were detected by ELISA in RA serum (n = 92), HC serum (n = 82). The red line indicates the mean value and the blue line indicates SD. Black dashed line represents the cutoff value used to determine positive reactivity (white dots) in experimental samples. The 95% percentile of HC samples was used to define the cutoff for positive antibody levels. Unpaired t-test was used as parametric test. D, E Correlation between the serum anti-cit-IGF2BP1 antibodies with the erythrocyte sedimentation rate (ESR) and Disease Activity Score 28 (DAS28) in RA patients (n = 92) were evaluated by Pearson correlation coefficient. ****P < 0.0001. ns, no significance.