Background Comparative data on serum biomarker profile in anti-citrullinated peptide/protein antibody positive (ACPA+) and ACPA negative (ACPA-) rheumatoid arthritis (RA) patients are scarce.
Objectives Our aim was to analyze serum levels of proteomic biomarkers in patients with RA according to the presence or absence of ACPA.
Methods We examined serum samples from 118 pts: 37 with early RA (<6 months disease duration, median and interquartile range (25th–75th percentile) of age 51 (41-62) years, 76% female, 79% ACPA+); 81 with established RA (>6 months disease duration, 49 (41-57) years, 88% female, 79% ACPA+). Patients were defined as ACPA - if serum was negative to three different ACPAs (second anti-CCP2, anti-MCV, anti-keratin antibodies). Anti-CCP2, anti-MCV, IgA RF was measured by ELISA; anti-keratin antibodies by indirect immunofluorescence assay; IgM RF by immunonephelometry. Cytokine analyses were performed with multiplex technology (Human Grp I Cytokine 27-plex panel for BioPlex 200).
Results ACPA+ with early RA had significantly higher levels of IgM RF, IL-15, G-CSF, with established RA – IgM/IgA RF, TNF-α, IL-15, -1ra, -2, -5, -9-10, -12, eotaxin, GM-CSF, MCP-1 than ACPA pts.
Conclusions ACPA+ patients had higher levels of RF, anti- and pro-inflammatory cytokines, colony-stimulating factors and chemokines than ACPA- patients.
Disclosure of Interest None declared