Abstract 18114: Generating Human Artery and Vein Cells From Pluripotent Stem Cells Highlights the Arterial Tropism of Nipah and Hendra Viruses

Introduction: biology research endeavors to generate specific subtypes of endothelial ‘‘cell types’’ such as artery and vein cells. Despite substantial progress, incomplete knowledge of artery and vein development challenges efforts to generate artery and vein cells from human pluripotent stem cells (hPSCs).

Hypothesis: We hypothesize that TGFb and PI3K are artery and vein-specifying signals, respectively. We can efficiently specify artery cells by inhibiting vein-specifying signals and vice versa in chemically defined media.

Methods: To generate artery cells, we activated TGFb and inhibited PI3K signaling (amongst other signals). Conversely, to generate vein cells, we inhibited TGFb and activated PI3K signaling.

Results: We generate >90% pure artery and >80% pure vein endothelial cells from hPSCs within 3-4 days of differentiation, respectively. Both artery and vein cells could form 3D blood vessel networks in vitro and in vivo , sense and respond to shear stress, and uptake low-density lipoproteins. These cells modeled viral infection of human vasculature by Nipah and Hendra viruses, which are extraordinarily deadly and require biosafety-level-4 containment. Generating pure populations of artery and vein cells showed that Nipah and Hendra viruses preferentially infected arteries; arteries expressed higher levels of their viral-entry receptor. Virally-infected artery cells fused into syncytia containing up to 23 nuclei, which rapidly died. Despite infecting arteries and occupying 6%-17% of their transcriptome, Nipah and Hendra largely eluded innate immune detection, minimally eliciting interferon signaling.

Conclusions: In conclusion, we efficiently generate artery and vein cells, introduce stem-cell-based toolkits for biosafety-level-4 virology, and explore the arterial tropism and cellular effects of Nipah and Hendra viruses. This large-scale supply of human endothelial cells could also enable applications, including vascular disease modeling and tissue engineering synthetic blood vessels.