Imagine a journey into the cellular structures of, well, nearly any living thing. From parasites that cause malaria to organisms in the nucleus of cancer cells.
Imagine seeing these microscopically small organisms in neon colours and imagine seeing them from all angles and in 3D.
This is exactly what scientists at Stellenbosch University (SU) can now do thanks to the state-of-the-art confocal LSM 780 microscope which is coupled to a super resolution ELYRA S1 platform. This microscope is one of the few that has for the first time broken the limit of resolution in light microscopy.
This image shows a cell with mitochondria (red), the organelles that produce energy. Mitochondria are dysfunctional in many disease states, including Neurodegeneration, Alzheimer’s and Parkinson’s disease. With the microscope scientists can now study this in much greater detail than was possible before. In green we see microtubili, a structural protein that gives the cell its skeleton and stability. In blue we see the nucleus that contains the DNA/the whole genetic information of the organism. In cancer cells that are treated and are dying, the nucleus shrinks, and the skeleton collapses.
A breakthrough is that samples can be kept alive – in contrast to other microscopes where samples die off.
“This is technology on the cutting edge,” says Dr Ben Loos, a lecturer and researcher in cell death in the brain and heart at the Physiology Department and Cell Imaging Unit, Central Analytical Facility at SU. “This technology is so new that only a few of these microscopes are available worldwide.”
Loos together with Prof Bert Klumperman, Research Chair on Advanced Macromolecular Architectures at SU made an application to the National Research Foundation (NRF) to obtain one of these microscopes which cost R8 million and had to be imported from Zeiss in Germany.
“Our application was supported not only by a large research community at SU, but also by the University of the Western Cape, the University of Cape Town, the University of Johannesburg, the University of Pretoria and the Cape Peninsula University of Technology,” says Loos. “Researchers from these institutions, but also any other academic or industry institutions will be able to use this microscope. We are incredibly excited and thankful that the NRF was willing to invest in this piece of technology and that SU co-invested and supported this venture all the way. It can be applied to a variety of disciplines and can really help to help researchers make interventions in illnesses that are killing millions of people.”
Mrs Lize Engelbrecht who is responsible for managing the microscope adds: “TB and malaria are areas of national importance and we can get right into the cells of the bacteria and parasites causing these illnesses and see how it responds to treatment. The great thing about this microscope is that we can look at live samples at high resolution. When treatment is given, we can monitor the progress at different stages. With other microscopes, for example transmission electron microscopy, the cells are killed off during the sample preparation. We can trace exactly where the treatment is affecting the cell.”
According to Loos the superresolution technology coupled to the confocal microscope makes it possible to zoom right into the cell to see exactly how it responds to treatment.
“In our case, we are focussing on imaging key proteins that may help us to prevent cell death, such as seen in neurodegeneration or infarction, so that the tissue can be rescued,” he says.
Both Loos and Engelbrecht emphasise that anything that fluoresces or can be labelled with a fluorochrome, can be imaged with this new instrument, from nano-and microcapsules, to TB bacteria and viral particles, cells and tissues, even polymer particles and fluorescing rock inclusions.
“We have a huge range of fluorochromes available as tools to label structures of interest and therefore the possibilities are endless,” says Engelbrecht.
As part of the application to the NRF, Loos and Klumperman had to provide proof of ground-breaking research done at the SU. Amongst others they focused on the work being done by Klumperman in the development of nanocapsules and microcapsules that are utilized as vehicles to deliver drugs specifically to cancer cells and nanofibres that may improve detection methods in TB.
Other major focus areas included water science, and more specifically the visualization of living or dead bacteria, work related to the “tea-bag” water filter that makes use of nanotechnology to turn contaminated water into safe drinking water, and the ground-breaking dressing that releases antimicrobial peptides through nanofibres in a slow and controlled manner to aid healing when applied to burn wounds. The tea-bag water filter was invented by microbiologist Prof Eugene Cloete (former Dean of the Faculty of Science at SU, and now the University’s new Vice-Rector for Research and Innovation) and his team, while the wound dressing was developed by his microbiology colleague at SU Prof Leon Dicks and his team.
The room in which the confocal microscope is housed had to be modified by closing up the windows to ensure that the room is as dark as possible when the lights are switched off. Because the microscope works with eight lasers and fluorescent dyes, the samples under the microscope are best viewed in darkness.
“The eight lasers provide us with a powerful spectrum of excitation possibilities, as each fluorochrome has its specific range of light that it needs to be excited with in order to emit light. When the molecules get excited by the laser light energy, they absorb it and “release” it as light in a specific colour. It is this emitted light that creates the colourful pictures,” says Loos.
“We are extremely excited that we have this ground-breaking technology, the only one of its kind, here at SU. So, let the work begin.” — STEPHANIE NIEUWOUDT