Transcriptome changes during Endothelial to Mesenchymal Transition (EndMT) using a TGF-b2 and IL-1b in vitro model of EndMT in HUVEC and HPAEC

Endothelial-to-mesenchymal transition (EndMT) is a dynamic transformation process that has a functional impact upon pathological vascular remodelling. However, the molecular mechanisms that govern EndMT remain largely unknown. We modelled this process in vitro by exposing human primary endothelial cells to a combination of transforming growth factor-β2 (TGF- β2) and interleukin-1β (IL-1β). RNAseq was carried out to analyse the change of gene expression during the transition and define the transcriptional architecture of EndMT. HUVEC (Human umbilical vein endothelial cells) cells were treated with TGF-β2 (10 ng/ml) alone, IL-1β (1ng/ml) alone as well as combined TGF-β2 and IL-1β for 7 consecutive days. HPAEC (Human pulmonary artery endothelial cells) cells were co-treated with TGF-β2 and IL-1β for 7 consecutive days. Control samples correspond to time-matched untreated cells. All treatments were carried out in triplicates and total RNAs were extracted for RNAseq. Ribosomal-depleted stranded libraries were prepared by Beckman Coulter Genomics using the TruSeq Stranded Total RNA kit with Ribo-Zero Gold. Libraries were sequenced with Illumina at an average of 50 million reads per samples (paired end 2 x 125bp).