Effect of Anisotropic Structural Depth on Orientation and Differentiation Behavior of Skeletal Muscle Cells

Abstract

Extensive research has been conducted to examine how substrate topological factors are involved in modulating the cell behavior. Among numerous topological factors, the vital influence of the touchable depth of substrates on cell behaviors has already been extensively characterized, but the response of cells to the topological structure at untouchable depth is still elusive. Herein, the influences of substrate depth on myoblast behaviors are systematically investigated using substrates with depths ranging from touchable depth (microgrooved) to untouchable depth (microbridges). The results show that an increase in microgroove depth is accompanied by an inhibited cell spreading, an enhanced elongation, and a more obvious orientation along microgrooves. Interestingly, myoblasts located on microbridges show a more pronounced elongation with increasing culture time but a position-dependent orientation. Myoblasts on the center and parallel boundary of microbridges orient along the bridges, while myoblasts on the vertical boundary align perpendicular to the microbridges. Moreover, the differentiation results of the myoblasts indicate that the differentiated myotubes can maintain this position-dependent orientation. The simulation of the stress field in cell monolayers suggests that the position-dependent orientation is caused by the comprehensive response of myoblasts to the substrate discontinuity and substrate depth. These findings provide valuable insights into the mechanism of cell depth sensing and could inform the design of tissue engineering scaffolds for skeletal muscle and biohybrid actuation.

Revealing Early Spatial Patterns of Cellular Responsivity in Fiber-Reinforced Microenvironments

“…The interplay between low and high response cells in terms of their localization within stiff-soft microenvironments can be crucial to optimizing fiber-reinforced technologies at the cellular level to maximize organization and alignment of eventual deposited tissue. Specifically, we have explored how the depth by which cells can sense a rigid fiber in a stiff-soft environment 34,36 can influence spatial patterning of the 3D fiber-reinforced microenvironment. By illustrating the distance-dependent nature by which cells spatially sense rigid material across a soft medium, we have provided insight into the dynamics of cell instruction, in terms of orientation and differentiation, by topological features of the cell-biomaterial network.…”

“…Understanding the dynamics by which cells sense within an anisotropic 3D environment can inform design strategies for fiber-reinforced scaffolds at the microscale. Specifically, cells can sense and respond to microenvironmental cues, such as anisotropic structural orientation and depth 34 , biophysical properties of the surrounding matrix (e.g., degradation and mechanics) 15,35 , and proximity to rigid materials (e.g., polymer fiber) in stiff-soft environments 36 . Through mechanosensing of these cues, downstream morphological behavior and patterning of the fiber-reinforced microenvironment can govern eventual tissue deposition and architecture 37,38 .…”

Dimensionality Matters: Exploiting UV-Photopatterned 2D and Two-Photon-Printed 2.5D Contact Guidance Cues to Control Corneal Fibroblast Behavior and Collagen Deposition

“…Furthermore, most studies mainly focus on the width of contact guidance cues. Excitingly, in recent years, more attention has been paid to the role of topography height, which is increasingly appreciated as an important parameter responsible for distinct cell behaviors [31][32][33]. Indeed, from previous in vitro research, it is known that cue dimensionality (e.g., topography width and height) can have a major influence on cell behavior [34,35].…”