Total RNA, including the miRNA fraction, was extracted from both plasma and supernatants obtained from in vitro studies by using the QIAzol miRNeasy kit (Qiagen, Valencia, CA, USA) following the manufacturer’s instructions13 (link) (Online Supplementary Appendix). To identify the changes that occurred in the expression levels of miRNAs in plasma from APS patients and HDs, a Human Serum & Plasma miRNA PCR-array (Qiagen) was performed (Online Supplementary Appendix) on an exploratory cohort (Online Supplementary Table S2).