Matrix-driven translocation of cells and nonliving particles

Cells of metazoan organisms produce and react to complex macromolecular microenvironments known as extracellular matrices. Assembly in vitro of native, compositionally nonuniform collagen-fibronectin matrices caused translocation of certain types of cells or polystyrene-latex beads from regions lacking fibronectin into regions containing it. The translocation process was not due to diffusion, convection, or electrostatic distribution effects, but may depend on nonequilibrium phenomena at the interface of contiguous collagen matrices formed in the presence and absence of fibronectin or particles. Extracellular matrix formation alone was sufficient to drive translocation by a biophysical process that may play a role in cellular migration during embryogenesis, as well as in other types of tissue reorganization such as inflammation, wound healing, and tumor invasion.