What Is the Right Mechanical Readout for Understanding the Mechanobiology of the Immune Response?

Quantitative Methodologies to Dissect Immune Cell Mechanobiology

“…This is of critical relevance for cells of the immune system, for example, T cells, which are highly dynamic and employ active force generation for antigen recognition and for cytotoxicity in mechanically diverse environments without losing their function [21,22]. Thus, to better understand the immune response, a mechanical description of cells and a proper quantification of their mechanical parameters are required [29]. Aiding in the understanding of different mechanical metrics, we highlighted the most common readouts, such as mechanical force, stiffness, stress, strain, pressure, tension, Young's modulus, viscosity and Poisson's ratio, in a cellular context.…”

“…Nevertheless, a full parametrization of cellular mechanics and their surroundings is required to further our understanding of mechanobiology. A variety of different mechanical parameters has been identified that could be used to characterize the mechanical behaviour of cells (Figure 1B) [29]. The great challenge is not only to identify the control parameter(s) to describe cell mechanics but also to determine which of the parameters cells themselves depend on to regulate and adapt their functions.…”

“…Crucially, the function of immune cells has been shown to depend both on the stiffness of their environment and mechanical forces applied to immune cell receptors [23][24][25][26][27][28]. Owing to this, mechanobiology is gaining increasing interest within the context of the human immune response, but fully elucidating the likely complex role of mechanics in immune cell function relies on the robust quantification of the relevant mechanical parameters with sufficient sensitivity [29]. This represents a significant challenge, given the multi-scale nature of immune cell biomechanics and the tissue microenvironment [3].…”