A new live-cell imaging technique, PCEM, has been invented by researchers from the University of Illinois at Urbana-Champaign. This might be helpful to biologists in understanding the spread of cancer and in understanding the transformation of stem cells into specialized cells.
The Photonic Crystal Enhanced Microscope (PCEM) has the ability to monitor and quantitatively measure cell adhesion, an important process required in various cellular activities like migration, differentiation, division, and cell death.
“This new approach is significant since there are no label-free and high-resolution imaging tools at present, that let interactions of the cell-surface be quantified and imaged dynamically, though these processes are basic to things such as wound healing, tumor invasion, tissue development and cancer metastasis,” mentioned Brian Cunningham, a professor of electrical and computer engineering and of bioengineering at Illinois.
Most common imaging methods depend on fluorescent dyes, which bind to and illuminate the components of the cell so they are visible with a microscope. But this method has its limitations. It is invasive and hard for quantitative measurement, and also allows only a short period of time for examining the cells and for measurement because of photo bleaching.
By using the PCEM microscopic technique, the researchers have successfully calculated the effective mass density of cell membranes during stem cell differentiation and the tumor cell response to drugs in an extended period. Their findings, “Quantitative imaging of cell membrane-associated effective mass density using Photonic Crystal Enhanced Microscopy,” were published in the journal Progress in Quantum Electronics, (November 2016, Volume 50).
Yue Zhuo, who led this research, is a post-doctoral Beckman Institute Fellow. He mentioned that, The common method of fluorescent tagging doesn’t allow researchers to view how a cell or protein alters over time.¯
“You can view the cell for only a few hours maximum until the fluorescent tagging dies out, but it requires many days to perform a stem cell experiment,” said Zhuo. “Scientists usually rely on fluorescent tagging since there’s no other better way to observe live cells due to their low imaging contrast among organelles of the cell. That urges us to build up a high-resolution imaging and label-free method to study live cells.”