The objective of the proposed work is to study the propulsion of biological cells that utilize their extremely deformable membrane to move. Cells can deform and extend a protrusion, called pseudopod, by streaming flow internally in a particular direction of the cell membrane, and the pseudopod is used to move the cell. This is a proposal to study the pseudopod-based propulsion of deformable cells from a fluid mechanical viewpoint using a combination of high-fidelity computational modeling, theoretical analysis and experimental measurements. In terms of impact on health, the project may provide a mechanistic understanding of how to inhibit propulsive mechanisms of malignant cells.
While fluid mechanical analysis of the streaming flow has been carried out recently in plant cells, which are non-deforming and non-propulsive, the relationship between the streaming flow, pseudopod dynamics, and motor activity is unknown in deformable cells. The co-PIs propose to develop a multiscale, 3D computational model of the interface deformation driven by molecular motors. The model will predict simultaneously the dynamic cell shape, the flow field, and motor activity. In parallel, micro-PIV experiments will be performed in live amoeboid cells to extract the 2-component quasi-instantaneous intra-cellular velocity field. Using analysis of the simulation and experimental data, the nature and origin of the streaming flow in deforming cells, and its relation to pseudopod dynamics will be explored. This award by the Fluid Dynamics Program of the CBET Division is co-funded by the Computational Mathematics Program in the Division of Mathematical Sciences.
