Versatile synthetic alternatives to Matrigel for vascular toxicity screening and stem cell expansion

The physiological relevance of Matrigel as a cell-culture substrate and in angiogenesis assays is often called into question. Here, we describe an array-based method for the identification of synthetic hydrogels that promote the formation of robust in vitro vascular networks for the detection of putative vascular disruptors and that support human embryonic stem cell expansion and pluripotency. We identified hydrogel substrates that promote endothelial-network formation by primary human umbilical vein endothelial cells and by endothelial cells derived from human-induced pluripotent stem cells, and used the hydrogels with endothelial networks to identify angiogenesis inhibitors. The synthetic hydrogels showed superior sensitivity and reproducibility over Matrigel when known inhibitors were evaluated, as well as in a blinded screen of a subset of 38 chemicals, selected according to predicted vascular disruption potential, from the Toxicity ForeCaster library of the United States Environmental Protection Agency. We propose that the identified synthetic hydrogels are suitable alternatives to Matrigel for common cell-culture applications. An array-based method can identify synthetic hydrogels that outperform Matrigel in screening for vascular-disruptor compounds and in supporting the expansion and pluripotency of human embryonic stem cells.