Abstract

In native states, animal cells are surrounded by either fluid or a biopolymer network. The cell-environment interactions critically regulate cell function, as well as collective cell motion. The key to this interaction is the biophysical forces that cells generate. In this talk, I will focus on experimental studies of single cell force regulation in two biological systems. One is on tumor cell-extracellular matrix interaction, in which we find that matrix mechanics, and fluid flows together regulate single tumor cell shape, motility types and invasiveness. In the case of a group of tumor cells, physical forces determine the formation or dissociation of tumor spheroids. In a second example, we studied how sperm cells swim against fluid flows guided by a hydrodynamic force. Curiously, in both cases, biological matrices/fluids enhance force transmission range and promote cell-cell interaction.