Fig. 2
From: Anti-citrullinated protein antibodies contribute to platelet activation in rheumatoid arthritis
ACPA-mediated activation of platelets from healthy subjects. Platelets were isolated from buffy coat and incubated in the presence of plasma obtained from ACPAneg or ACPApos patients with RA (matched for age, sex and DAS44; cohort 2). To ensure we were studying active disease, only plasma samples from patients with a DAS44 > 2.4 were included. Plasma from ACPApos patients with RA induced higher platelet activation than did plasma from ACPAneg patients with RA, as indicated by increased (a) percentage and (b) MFI of CD62P expression and (d) platelet aggregation. c Histogram overlay showing representative examples of CD62P expression. e Representative pictures of aggregate formation and CD62P expression of non-aggregated and aggregated platelets. f Levels of P-selectin correlated with high ACPA titres (> 1000 AU/ml). Each symbol represents a plasma sample. ACPA anti-citrullinated protein antibodies, CD62P P-selectin, DAS44 Disease Activity Score in 44 joints, FSC forward scatter, MFI mean fluorescence intensity, RA rheumatoid arthritis, SSC side scatter