Complement deposition on platelets in SLE patients is associated with aCL antibodies and platelet activation.

<p>A) Platelet expression of C4d was analyzed in 148 SLE patients and grouped into patients with or without anti-phospholipid (aPL) or anti-cardiolipin (aCL) antibodies at the time of blood sampling. The line represents the median value in each group. B) Platelet expression of CD69 was measured by flow cytometry in healthy volunteers (HV), patients with systemic lupus erythematosus (SLE), rheumatoid arthritis (RA), systemic sclerosis (SSc) and myocardial infarction (MI). The line represents the median value in each group. C) Correlation analysis between C1q deposition on platelets and platelet activation marker CD69 in the 148 SLE patients.