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 thi
|Contact: Dr. Katharina Gaus|
University of New South Wales