To achieve organization and function, engineered tissues require a scaffold that supports cell adhesion, alignment, growth, and differentiation. For skeletal muscle tissue engineering, decellularization has been an approach for fabricating 3D scaffolds that retain biological architecture. While many decellularization approaches are focused on utilizing animal muscle as the starting material, decellularized plants are a potential source of highly structured cellulose-rich scaffolds. Here, we assessed the potential for a variety of decellularized plant scaffolds to promote mouse and human muscle cell alignment and differentiation. After decellularizing a range of fruits and vegetables, we identified the green-onion scaffold to have appropriate surface topography for generating highly confluent and aligned C2C12 and human skeletal muscle cells (HSMCs). The topography of the green-onion cellulose scaffold contained a repeating pattern of grooves that are approximately 20 μm wide by 10 μm deep. The outer white section of the green onion had a microstructure that guided C2C12 cell differentiation into aligned myotubes. Quantitative analysis of C2C12 and HSMC alignment revealed an almost complete anisotropic organization compared to 2D isotropic controls. Our results demonstrate that the decellularized green onion cellulose scaffolds, particularly from the outer white bulb segment, provide a simple and low-cost substrate to engineer aligned human skeletal muscle.

Endothelial cells (EC) respond to shear stress to maintain vascular homeostasis, and a disrupted response is associated with cardiovascular diseases. To understand how different shear stress modalities affect EC morphology...

Endothelial cells (EC) respond to shear stress to maintain vascular homeostasis, and a disrupted response is associated with cardiovascular diseases. To understand how different shear stress modalities affect EC morphology and behavior, we developed a microfluidic device that concurrently generates three different levels of uniform wall shear stress (WSS) and six different WSS gradients (WSSG). In this device, human umbilical vein endothelial cells (HUVECs) exhibited a rapid and robust response to WSS, with the relative positioning of the Golgi and nucleus transitioning from non-polarized to polarized in a WSS magnitude- and gradient-independent manner. By contrast, polarized HUVECs oriented their Golgi and nucleus polarity to the flow vector in a WSS magnitude-dependent manner, with positive WSSG inhibiting and negative WSSG promoting this upstream orientation. Having validated this device, this chip can now be used to dissect the mechanisms underlying EC responses to different WSS modalities, including shear stress gradients, and to investigate the influence of flow on a diverse range of cells during development, homeostasis and disease.