Biomimetic microchannel network with functional endothelium formed by sacrificial electrospun fibers inside 3D gelatin methacryloyl (GelMA) hydrogel models

Three-dimensional (3D) hydrogel models play a crucial role in tissue engineering for promoting tissue regeneration. A biomimetic microchannel network system in the 3D hydrogel model is necessary for optimal cellular function. This report describes the preparation of a biomimetic hydrogel scaffold with an internal microchannel network, using electrospinning techniques and the sacrificial template method for 3D cell culture. Microchannels and cavities were created within the gelatin methacryloyl (GelMA) hydrogel by sacrificing polyvinyl alcohol (PVA) electrospun fibers (>10 µm), resulting in the creation of microvessel-like channels. Mechanical characterizations, swelling properties, and biodegradation analysis were conducted to investigate the feasibility of a biomimetic microchannel network hydrogel scaffold for 3D cell culture applications. Compared to pure GelMA hydrogel, the hydrogel with microchannels promoted cell proliferation, adhesion, and endothelial tube formation. Moreover, the results confirmed that the biomimetic microchannel network scaffold had a major impact on the distribution and arrangement of human umbilical vein endothelial cells (HUVECs) and can enable the formation of artificial microvasculature by the culture of HUVECs and cell media perfusion.