Phototuning of Hyaluronic‐Acid‐Based Hydrogel Properties to Control Network Formation in Human Vascular Endothelial Cells
Kelum Chamara Manoj Lakmal Elvitigala, Lakshmi Mohan, Wildan Mubarok, Shinji Sakai
Abstract
Abstract In vitro network formation by endothelial cells serves as a fundamental model for studies aimed at understanding angiogenesis. The morphogenesis of these cells to form a network is intricately regulated by the mechanical and biochemical properties of the extracellular matrix. Here the effects of modulating these properties in hydrogels derived from phenolated hyaluronic acid (HA‐Ph) and phenolated gelatin (Gelatin‐Ph) are presented. Visible‐light irradiation in the presence of tris(2,2′‐bipyridyl)ruthenium(II) chloride hexahydrate and sodium persulfate induces the crosslinking of these polymers, thereby forming a hydrogel and degrading HA‐Ph. Human vascular endothelial cells form networks on the hydrogel prepared by visible‐light irradiation for 45 min (42 W cm −2 at 450 nm) but not on the hydrogels prepared by irradiation for 15, 30, or 60 min. The irradiation time‐dependent degradation of HA‐Ph and the changes in the mechanical stiffness of the hydrogels, coupled with the expressions of RhoA and β‐actin genes and CD44 receptors in the cells, reveal that the network formation is synergistically influenced by the hydrogel stiffness and HA‐Ph degradation. These findings highlight the potential of tailoring HA‐based hydrogel properties to modulate human vascular endothelial cell responses, which is critical for advancing their application in vascular tissue engineering.