iPSC-Derived Brain Endothelium Exhibits Stable, Long-Term Barrier Function in Perfused Hydrogel Scaffolds

Abstract

Summary: There is a profound need for functional, biomimetic in vitro tissue constructs of the human blood-brain barrier and neurovascular unit (NVU) to model diseases and identify therapeutic interventions. Here, we show that induced pluripotent stem cell (iPSC)-derived human brain microvascular endothelial cells (BMECs) exhibit robust barrier functionality when cultured in 3D channels within gelatin hydrogels. We determined that BMECs cultured in 3D under perfusion conditions were 10–100 times less permeable to sodium fluorescein, 3 kDa dextran, and albumin relative to human umbilical vein endothelial cell and human dermal microvascular endothelial cell controls, and the BMECs maintained barrier function for up to 21 days. Analysis of cell-cell junctions revealed expression patterns supporting barrier formation. Finally, efflux transporter activity was maintained over 3 weeks of perfused culture. Taken together, this work lays the foundation for development of a representative 3D in vitro model of the human NVU constructed from iPSCs. : Faley et al. present a 3D in vitro model of the blood-brain barrier constructed using induced pluripotent stem cell-derived human brain microvascular endothelial cells cultured in 3D channels in gelatin hydrogels. The model displays robust tight junction protein expression, restricted paracellular permeability, and active efflux transporter activity, and represents an important step toward a representative human in vitro neurovascular model. Keywords: induced pluripotent stem cell, blood-brain barrier, neurovascular unit, three dimensional model, tissue engineering