Cell Mechanics
Cell mechanics is a multidisciplinary field that investigates the physical principles governing the behaviour and properties of cells. This area encompasses various concepts such as membrane elasticity, active matter, self-assembly, and collective mechanics. Membrane elasticity refers to the ability of the cell membrane to deform and return to its original shape, which is crucial for processes like cell division and movement. Active matter involves systems where components consume energy to generate motion, exemplified by the dynamic cytoskeleton. Self-assembly is the spontaneous organization of molecules into structured arrangements, fundamental to cellular architecture. Collective mechanics examines how groups of cells interact and behave as a collective entity, essential for tissue and organ function.
Our current research ins this field focuses on the mechanics of red blood cells, particularly their aggregation and formation of percolating networks. This phenomenon is vital for understanding blood storage conditions and improving diagnostic tests. Red blood cells (RBCs) can also be seen as a model system, as their high flexibility and anisotropy lead to different collective dynamics than the ones of hard spheres. By studying how mechanical properties of individual RBCs modify the dynamic properties of the overall suspension, we aim to enhance the accuracy and effectiveness of hematological tests.
Our previous work, integrating fluid dynamics and cell mechanics, lead to improved hematological diagnostics based on Erythrocyte Sedimentation Rate (ESR) (Fig. 1). For instance, we made it possible to correct the ESR as a function of the donor’s hematocrit (i.e. RBCs native hematocrit), a feat that eluded this protocol for more than a century. These improvements underscore the importance of understanding blood cell mechanics to develop better diagnostic tools and treatments for blood-related disorders.
Sedimentation of Red Blood Cells, along quantitative sedimentation speed measurements for various hematocrits. Figure adapted from Darras et al. and Dasanna et al.
https://doi.org/10.1103/PhysRevLett.128.088101
https://doi.org/10.1103/PhysRevE.105.024610