The relative extensibility of cell surfaces.

Observations have been made on the response, in vitro, of cultured and freshly dissociated cells to mechanical deformation. Large numbers of individual cells were studied by means of a special culture chamber bounded by two parallel glass coverslips whose spacing could be reduced from 140 to 2 microns in steps of roughly 0.5 micron. The degree of deformation required for herniation of the cell surface was measured. These measurements lead to the definition of a statistical index characteristic of the extensibility of cell surfaces. This index has been shown to be distinctive for several types of cells; to alter with certain stages of embryonic development; and to be stable with respect to the culturing of cells and certain alterations in the method of cell culture.