Cell motility in a new single-cell wound model.

Until now researchers have used a monolayer of cultured cells to investigate cell motility toward an injured cell. However, we suspect that, when using this method, adjacent cells move to the free space due to relief of contact inhibition. The current study was designed to investigate the cell motility nearby an injured cell in varying cell connectivity. A low-power laser beam was used to damage one cell selectively with the silver coating beads. After injury, we observed the cell motility in three different cell types: (1) those immediately adjacent to the injured cell, (2) those removed from the injured cell by interposition of another cell, and (3) those removed from the injured cell by free space. The cells that are in direct contact with the injured cell moved toward the injured cell within 1.5-3.0 h. Indirectly connected cells and cells with no contact, on the other hand, showed no significant movement toward the injured cell. This suggests that the cell motility toward the cell injury is not only due to relief of contact inhibition but might also be caused by cell-to-cell signaling via cell connection. The current method will provide a tool to create a cell injury without damaging adjacent cells.