Single-cell transcriptome analysis of endothelial cell heterogeneity under laminar shear stress

Heterogeneity of endothelial cells that form the innermost layer of all vessels is critical for vascular sprouting and angiogenesis. After new vessels form, endothelial cell heterogeneity is believed to be gradually lost as vessels respond to flow-mediated signals, mature, remodel and become homeostatic. However, whether and at what level endothelial cell lost heterogeneity is poorly understood. Here we investigated heterogeneity change of endothelial cells under homeostatic laminar shear tress in comparison to static cultures. We performed single-cell RNA sequencing of human umbilical vein endothelial cells (HUVEC) cultured under static condition or flowed under 15 dynes/cm2 laminar shear (Ibidi µ-Slide I Luer) for 72 hrs. Static and Flow samples were collected from two independent experiments (replicates) and sequenced using the 10x Genomics platform. To check doublet rate, 10% MEF were mixed with each sample of HUVEC right before loading onto 10X Genomics Chromium Controller for droplet generation.