Changes in the mechanical properties of single cells are related to the physiological state and fate of cells. The construction of cell constitutive equations is essential for understanding the material characteristics of single cells. With the help of atomic force microscopy, bio-image processing algorithms, and other technologies, research investigating the mechanical properties of cells during static/quasi-static processes has developed rapidly. A series of equivalent models, such as viscoelastic models, have been proposed to describe the constitutive behaviors of cells. The stress-strain relations under dynamic processes are essential to completing the constitutive equations of living cells. To explore the dynamic mechanical properties of cells, we propose a novel method to generate a controllable dynamical compression shear coupling stress on living cells. A CFD model was established to visualize this method and display the theories, as well as assess the scope of the application. As the requirements or limitations are met, researchers can adjust the details of this model according to their lab environment or experimental demands. This micro-flow channel-based method is a new tool for approaching the dynamic mechanical properties of cells.

Traumatic brain injury (TBI), which is mainly caused by impact, often results in chronic neurological abnormalities. Since the pathological changes in vivo during primary biomechanical injury are quite complicated, the in-depth understanding of the pathophysiology and mechanism of TBI depends on the establishment of an effective experimental in vitro model. Usually, a bomb explosive blast was employed to establish the in vitro model, while the process is complex and unsuitable in the lab. Based on water-hammer, we have developed a device system to provide a single dynamic compression stress on living cells. A series of amplitude (∼5.3, ∼9.8, ∼13.5 MPa) were generated to explore the effects of dynamic compression loading on primary microglia within 48 h. Apoptosis experiments indicated that primary microglia had strong tolerance to blast waves. In addition, the generation of intercellular reactive oxygen species and secretory nitric oxide was getting strongly enhanced and recovered within 48 h. In addition, there is a notable release of pro-inflammatory cytokine by microglia. Our work provides a reproducible and peaceable method of loading single dynamic compression forces to cells in vitro. Microglia showed an acute inflammatory response to dynamic loadings, while no significant cell death was observed. This insight delivers a new technological approach that could open new areas to a better understanding of the mechanism of cell blast injuries.