Optical tweezers, microfluidics reveal environmental impact on single cells

A new method of studying single cells while exposing them to controlled environmental changes uses optical tweezer technology to move the cell around in a microscopic channel system. The approach, developed by researchers at the University of Gothenburg (Sweden), allows observation of how individual cells react to stress induced by a constantly changing environment.

The approach gives researchers information that would not be possible to obtain with traditional methods. Such studies have traditionally used cultures consisting of millions of cells--and thus reveal reactions of cell groups but not individual responses.

PhD student Emma Eriksson and her colleagues at the university's Department of Physics developed a method where laser tweezers are used to catch a cell and then move it between different environments in microfluidic channels while observing reactions through a microscope. A cell can thus be exposed to tests and various substances for very exact time periods, which enables the researchers to repeatedly add and remove a substance to see how it affects the behavior of the cell.

In its first stage, the new method has been tested on yeast cells. One of the cells' proteins was tagged with a green fluorescent protein (GFP), enabling researchers to trace the movements of the protein within the cell while it adjusts to a new environment.

"The information gained from this may eventually lead to a better understanding of how cells work and what they do to stay alive and healthy in a constantly changing environment," says Eriksson.

For more information see the paper "Optical systems for single cell analyses" in Expert Opinion on Drug Discovery.