Using the only microscope of its kind in Australia, medical scientists have been able for the first time to see the inner workings of T-cells, the front-line troops that alert our immune system to go on the defensive against germs and other invaders in our bloodstream.
The discovery overturns prevailing understanding, identifying the exact molecular 'switch' that spurs T-cells into action — a breakthrough that could lead to treatments for a range of conditions from auto-immune diseases to cancer.
The findings, by researchers at the University of New South Wales (UNSW), are reported this week in the high-impact journal Nature Immunology.
Studying a cell protein important in early immune response, the researchers led by Associate Professor Katharina Gaus from UNSW's Centre for Vascular Research at the Lowy Cancer Research Centre, used Australia's only microscope capable of super-resolution fluorescence microscopy to image the protein molecule-by-molecule to reveal the immunity 'switch'.
The technology is a major breakthrough for science, Dr Gaus said. Currently there are only half a dozen of the 'super' microscopes in use around the world.
"Previously you could see T-cells under a microscope but you couldn't see what their individual molecules were doing," Dr Gaus said.
Using the new microscope the scientists were able to image molecules as small as 10 nanometres. Dr Gaus said that what the team found overturns the existing understanding of T-cell activation.
"Previously it was thought that T-cell signalling was initiated at the cell surface in molecular clusters that formed around the activated receptor.
"In fact, what happens is that small membrane-enclosed sacks called vesicles inside the cell travel to the receptor, pick up the signal and then leave again," she said.
Dr Gaus said the discovery explained how the immune response could occur so quickly.
"There is this rolling amplification. The signalling station is like a docking port or an airport with vesicles like planes landing and taking off. The process allows a few receptors to activate a cell and then trigger the entire immune response," she said.
PhD candidate David Williamson, whose research formed the basis of the paper, said the discovery showed what could be achieved with the new generation of super-resolution fluorescence microscopes.
"In conventional microscopy, all the target molecules are lit up at once and individual molecules become lost amongst their neighbours – it's like trying to follow a conversation in a crowd where everyone is talking at once.
"With our microscope we can make the target molecules light up one at a time and precisely determine their location while their neighbours remain dark. This 'role call' of all the target molecules means we can then build a 'super resolution' image of the sample," he said.
The next step was to pinpoint other key proteins to get a complete picture of T-cell activity and to extend the microscope to capture 3-D images with the same unprecedented resolution.
"Being able to see the behaviour and function of individual molecules in a live cell is the equivalent of seeing atoms for the first time. It could change the whole concept of molecular and cell biology," Mr Williamson said.
Other research team members were physicist Dr Dylan Owen, cell biologists Dr Jérémie Rossy and Dr Astrid Magenau, from the Centre for Vascular Research, and Professor Justin Gooding and Matthias Wehrmann, from UNSW's School of Chemistry and the Australian Centre for Nanomedicine. The research was supported by funding from the National Health and Medical Research Council, Australian Research Council and Human Frontier Science Program.
Dr. Katharina Gaus | EurekAlert!
Climate Impact Research in Hannover: Small Plants against Large Waves
17.08.2018 | Leibniz Universität Hannover
First transcription atlas of all wheat genes expands prospects for research and cultivation
17.08.2018 | Leibniz-Institut für Pflanzengenetik und Kulturpflanzenforschung
New design tool automatically creates nanostructure 3D-print templates for user-given colors
Scientists present work at prestigious SIGGRAPH conference
Most of the objects we see are colored by pigments, but using pigments has disadvantages: such colors can fade, industrial pigments are often toxic, and...
Scientists at the University of California, Los Angeles present new research on a curious cosmic phenomenon known as "whistlers" -- very low frequency packets...
Scientists develop first tool to use machine learning methods to compute flow around interactively designable 3D objects. Tool will be presented at this year’s prestigious SIGGRAPH conference.
When engineers or designers want to test the aerodynamic properties of the newly designed shape of a car, airplane, or other object, they would normally model...
Researchers from TU Graz and their industry partners have unveiled a world first: the prototype of a robot-controlled, high-speed combined charging system (CCS) for electric vehicles that enables series charging of cars in various parking positions.
Global demand for electric vehicles is forecast to rise sharply: by 2025, the number of new vehicle registrations is expected to reach 25 million per year....
Proteins must be folded correctly to fulfill their molecular functions in cells. Molecular assistants called chaperones help proteins exploit their inbuilt folding potential and reach the correct three-dimensional structure. Researchers at the Max Planck Institute of Biochemistry (MPIB) have demonstrated that actin, the most abundant protein in higher developed cells, does not have the inbuilt potential to fold and instead requires special assistance to fold into its active state. The chaperone TRiC uses a previously undescribed mechanism to perform actin folding. The study was recently published in the journal Cell.
Actin is the most abundant protein in highly developed cells and has diverse functions in processes like cell stabilization, cell division and muscle...
17.08.2018 | Event News
08.08.2018 | Event News
27.07.2018 | Event News
17.08.2018 | Physics and Astronomy
17.08.2018 | Information Technology
17.08.2018 | Life Sciences