Image Correlation Spectroscopy
The measurement of macromolecular transport properties and concentrations of biological molecules is of great interest to cell biologists. One of the common microscopy methods developed for this end is Fluorescence correlation spectroscopy (FCS). This technique uses a microscope lens to define a defraction excitation volume from which fluorescent photons are collected/measured as a function of time. This time variation of the counts is directly linked to the fluctuations in the concentration of molecules. Not only is FCS able to make these quantitative measurements (ie.concentrations and transport), but it can also measure molecular aggregation states in intact cells. This is significant because many signal transduction processes involve protein oligomerization.
While the use of FCS is biologically significant, it requires fixed preparations and can be a slow process (little info, many measurements). Dr. Paul Wiseman (McGill university) and colleagues have developed an extension to FCS which can solves these problems. Termed as Image Correlation spectroscopy (ICS), this method is based on quantitative analysis of confocal microscopy images which can be generated and measured rapidly. Although with ICS, precision decreases (due to lower resolution), the speed obtained is a good tradeoff.
As part of a collaboration between Dr. Paul Wiseman and Dr. Sergio Grinstein, the initiative behind this project was to bring the ICS/ICCS software to the SickKids imaging facility (manager: Mike Woodside) in order to apply its value to real biological research. Under the direction of Dr. Grinstein and Mike Woodside, the CCB has the role to provide the technical application of the ICS software in real biological settings. With the collaboration of Dr. Shoshana Wodak and Dr. Anatoly Malevanets, the current status of the project is the state of learning and applying the exact nature of the software in test scenarios using sample images. These include the measurement of particle concentration, directed flow and diffusion.
Principal Investigator
Dr. Sergio Grinstein, Senior Scientist
Dr. David Bazett-Jones, Director Advanced Bioimaging Centre, Bazett-Jones Lab
Collaborators
Dr. Shoshana Wodak and Dr. Anatoly Malevanets, Wodak Lab
