Until recently, it was unknown within the scientific community whether or not there was a master “on/off switch” for the human immune system. Australian scientists, however, have been able to demonstrate with a Supermicroscope the exact molecular “switch” that kicks T-cells into action.
T-cells are the front-line troops that give the signal to our immune system there is a need to go on the defensive against any invaders.
As reported in the journal Nature Immunology, the researchers, led by Associate Professor Katharina Gaus of UNSW’s Centre for Vascular Research at the Lowy Cancer Research Centre, were able to use Australia’s only Supermicroscope, an instrument capable of super-resolution fluorescence microscopy to image the protein molecule by molecule. Researchers had before been able to view T-cells, but could not see into the inner-workings, and therefore could not determine what the individual molecules were doing.
In conventional microscopy, all molecules within a cell are lit up at once, and individual molecules get lost in the crowd. With the Supermicroscope, researchers are able to light up one molecule at a time, leaving the surrounding molecules dark, allowing for observation and imaging of very targeted molecules.
Most scientists, previously had believed that T-cell signaling began at the cell surface, in molecular cluster that developed around an activated receptor. What the researchers at the University of New South Wales (UNSW) were able to prove is a major breakthrough for science. Instead of originating in the molecular cluster, as was believed, small membrane-enclosed vesicles, or sacks, travel to the receptor site, pick up the signal, and then leave again.
What this does for the immune system, is create a form of rolling amplification. According to Dr. Gaus, “The signaling 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 system.” This explains how the immune system can react so quickly to an invasion.
Scientists are eager to utilize this breakthrough and explore the possibility that this could lead to advanced treatments for conditions ranging from autoimmune diseases to cancer.
