Evaluating Morphology and Functionality of On-Chip Vascular Network Derived from Human Umbilical Vein Endothelial Cells (HUVECs) during Long-Term Culture

Abstract

Oxygen and nutrient supply provided via the vascular system is essential for organ development and tissue metabolism. Recent advances in stem cell technologies have led to the development of complex 3D tissue culture systems. However, direct supply of nutrients and oxygen by simple diffusion fails to reach inner areas resulting in impaired maturity of these complex tissues over time. In an attempt to alleviate this problem, 3D tissues are integrated with vascular networks (VNs) on a chip to ensure appropriate oxygen and nutrient supply. Such an in vitro vascular system must maintain a stable, robust, and perfusable network without degradation during entire culture period that may easily exceed several weeks. Current protocols for generation of VNs provide no information on the changes in these parameters in the long term. Here, using human umbilical vein endothelial cells, we generated a vascular network on a microfluidic chip and evaluated its morphology and function for 35 days. We demonstrate network stability, preservation of lumen structure and robust perfusability with negligible increase in permeability over time.