Latest News
August 27, 2019
In a world first, C4TS researchers have discovered that small proteins released by the injured tissues of trauma patients punch holes in platelets, causing them to swell into balloon structures.
Image above shows ballooning platelets (circled in red) compared to normal platelets (circled in blue).
Lead researcher Dr Scarlett Gillespie explains the process and significance of this research:
"Over the last 5 years our team has been working to understand what happens to platelet function after Trauma. Platelets are small cell fragments that stick together making blood clots and scabs that try to seal off damaged blood vessels. This process is essential to heal damaged vessels and stop you bleeding to death after injury.
Our team, and other international researchers, were aware that rapid changes in platelet function occur after Traumatic injury as they quickly become less sticky, however, we had seen that they were still able to be activated. In work presented in our recently published PNAS journal article, we set out to find out the processes that lead to these changes in platelet function.
Previous researchers in our group found that histones, tiny proteins that normally bind DNA, get released from cells in massive quantities following major injury. In our paper we present data showing that these histones bind to the surface of platelets and cause dramatic changes in the platelets architecture. The platelets blow up into balloon like structures. These balloons are fragile and eventually burst, releasing a surge of microparticles. Using imaging technologies were we able to detect these microparticles on the surface of white blood cells circulating in trauma patients’ bloodstream. We believe the binding of balloon derived microparticles to white blood cells could lead to changes in the body’s immune system. This is important as we know the immune system quickly changes after Trauma and are working to understand why this happens.
(Image left shows a neutrophil bound by platelet derived particles)
"This work detected platelet balloons for the first time in a human disease. It significantly expands our understanding of how and why platelet function changes after trauma. It also raises the possibility that these ballooned platelets drive changes in the immune system.
Our future work will focus on understanding how these platelet-immune cell interactions modulate the immune system and whether they play a role in the development of organ damage in trauma patients post injury."
For more information:
Research paper: ‘Histone H4 induces platelet ballooning and microparticle release during trauma hemorrhage’. Paul Vulliamy, Scarlett Gillespie, Paul C. Armstrong, Harriet E. Allan, Timothy D. Warner, and Karim Brohi. PNAS. DOI: 10.1073/pnas.1904978116
