A Method for In-Situ Targeting and Harvesting of Cultured Cells Under a Microscope

A new technique was developed to select and harvest cultured cells that are targeted under a microscope. It utilizes a thermo-responsive dish on which cells are adhesive at temperatures above ~33degC and are separated from the surface only by cooling. The principle of the technique is to culture cells on a thermo-responsive dish, cool locally beneath a cell that are observed under a microscope, and harvest detached cells that lost their extracellular matrix using a micropipette. We developed a thermo-responsive dish by coating polymers, a mixture of poly (N-isopropylacrylamide) (PNIPAAm) and PNIPAAm-grafted gelatin. A device was also developed to cool only a small part of the bottom of the dish beneath a cell that was targeted under a microscope. It was demonstrated that a cell or two cells that adhered each other were detached from the surface and harvested by a micropipette within about thirty seconds