One cell, two images: Conventional (top) and super-resolved (bottom).
The fluorescent green blob might look like something from outer space, but trillions of these bizarre-looking objects circulate around your body.
The image shows the contents of an individual human immune cell, a soldier in the body’s defence system tasked with attacking foreign invaders such as viruses and bacteria.
Never before have researchers viewed these fighter cells in such superior detail. A new generation of super-resolution microscopes can capture images of objects 10 nanometers (or 10 billionths of a metre) in size - about 700 times smaller than a red blood cell.
While the laws of physics mean conventional microscopes cannot resolve images smaller than 200 to 300 nanometres in size, University of NSW cell biologist Katharina Gaus has, with help from industry, designed a super-resolution microscope that overcomes this limitation.
Her microscope takes thousands of frames of a single cell. In each image a different component or part of the cell is highlighted by fluorescent markers.
“We take 20,000 frames of one cell and merge them into one super-resolved image,” Professor Gaus said. The image above shows thousands of proteins inside an immune T-cell.
For her work in this field, Professor Gaus was awarded on Wednesday a prestigious Elizabeth Blackburn Fellowship, one of 20 research excellence awards handed out by the National Health and Medical Research Council, the country’s major medical research funding body.
Professor Gaus is studying these images to understand how T-cells decide which molecules they attack and which they leave alone.
“There are hundreds of proteins involved in this decision-making process at a single cell level,” she said. Visualising them means her team can piece together patterns of how they behave.
When a T-cell identifies a foreign invader such as a virus it can trigger the a full-scale immune response to rid the body of the infection, said Professor Gaus. But these same cells could also ignore molecules released by tumours, promoting cancer growth.
T-cells could also misfire and set upon the body’s own cells, which could lead to auto-immune diseases such as multiple sclerosis or Crohn’s disease, she said.
“The decision-making machinery can’t be just an on and off switch," Professor Gaus said.
"They need to pick out subtle changes in their environment and make differentiated decisions,” she said.
Professor Gaus hopes her work may lead to future immune therapies that can train T-cells to target cancer cells.