Biopsy on living cells by ultra slow instrument movement

Biotechnology and regenerative medicine require more and more nondestructive and gentle single cell characterization and manipulation. We surmise here that such cell manipulation can be gently performed by the ultra slow movement (<50 μm h-1) of a probe or recovery tool. This extremely slow instrument velocity is adapted to the natural cellular processes of cytoskeleton and membrane reorganization. Here we describe for the first time the following surprising effects, which occur as a result of ultra slow instrument motion. (i) Parts of individual cells enveloped by the plasma membrane can be cut from the cell body without destroying the cell. Both parts migrate over hours and the part with the nucleus continues its normal cell migration and growth. Separated parts from cells can be used for immunohistochemical staining. (ii) Two adherently growing and partly overlapping cells can be fused by ultra slow instrument movement through the overlapping cell region. (iii) Relatively large instruments penetrating the cell membrane can be moved inside a cell without damage. (iv) The direction of cell migration can be controlled by ultra slow tool procedures. It thus seems that extremely slow instrument motion is potentially a new manipulation technique for in vitro culture and opens up a variety of handling devices