PBMC isolation and RNA extraction
Ficoll density gradient centrifugation was used to collect PBMCs from AS
and control patient blood samples using room temperature Lymphoprep
(Stemcell, USA). Next, a MiRNeasy Mini Kit (Qiagen, Germany) was
utilized for extraction of total RNA from these cells which was then
purified, quantified, and assessed for quality as discribed in a prior
study[23].