Manipulating the genetic identity and biochemical surface properties of individual cells with electric-field-induced fusion

摘要

A method for cell-cell and cell-liposome fusion at the single-cell level is described. Individual cells or liposomes were first selected and manipulated either by optical trapping or by adhesion to a micromanipulator-controlled ultramicroelectrode. Spatially selec- tive fusion of the cell-cell or cell-liposome pair was achieved by the application of a highly focused electric field through a pair of 5-μm o.d. carbon-fiber ultramicroelectrodes. The ability to fuse together single cells opens new possibilities in the manipulation of the genetic and cellular makeup of individual cells in a controlled manner. In the study of cellular networks, for example, the alter- ation of the biochemical identity of a selected cell can have a profound effect on the behavior of the entire network. Fusion of a single liposome with a target cell allows the introduction of the liposomal content into the cell interior as well as the addition of lipids and membrane proteins onto the cell surface. This cell- liposome fusion represents an approach to the manipulation of the cytoplasmic contents and surface properties of single cells. As an example. we have introduced a membrane protein (γ-glutamyl- transferase) reconstituted in liposomes into the cell plasma mem- brane.