For Non-scientists

 

What we do

At low magnification the cells of our bodies are appear to be just a bag full of a living “soup” that has the ability to grow and divide. At higher magnification most cells appear to be divided up in “compartments” that are specialised to do different jobs. The functions of these compartments are crucial for cell survival. Some cell compartments are still not well known or even wait to be discovered and electron microscopes are a very good way to find out the structure organization and function of these structures. We discovered a tiny organelle in a human parasite using this method. In human diseases the function of cell compartments and the cell/space around them is changed and these changes can be followed by electron microscopy because changes in structure and molecule composition provide important clues as to the defects. So how small can we go? Nowadays it is possible to visualize structures as small as individual proteins down to 1 billionth of a meter and by slicing frozen cells we can produce images of the cell structures and even the proteins, exactly in the places where they are functioning.

 

Immuno EM

We can also find out how much of the protein is there and whether it is in the right place. This is done by probing a very thin slice of a cell with antibodies that cling to a specific cell component such as a protein. Using this approach we have also pioneered methods for localizing the specialized fatty substances that are important for sending signals across membranes and into the cell. 

 

Stereology

We can also assess with extreme accuracy the amount of any cell compartment, whichagain gives us strong clues to cell function in health and disease. This approach is based on a solid foundation of maths but is rather simple to do. Using a lottery based approach to give all parts of the cell equal chance of being examined we can assess “how much” and “how many” by simple counting procedures that usually take minutes to do.

 

Tomography

More recently a technique akin to CAT scanning has revolutionized cell imaging. By tilting slices of cells we can get computers to reconstruct tiny portions of cell substance and see cell compartments in unprecedented detail.

Using these techniques we can put together a quantitatively accurate, and in depth, view of cell structure and its molecules. We are currently obtaining new results on the function of tiny compartments that are essential for the survival of human parasites. We are also working to improve the methods so we can work faster and produce more reliable electron microscope measurements . We are also planning to improve the methods (1) for locating the lipids of cells and (2) for characterizing nanoparticles that are important in delivering drugs, in diagnosis and in improving cosmetics.