Researchers from Flinders University and partners around the world have found out why a very small number of people get blood clots after some COVID‑19 vaccines that use an adenovirus carrier.
Mix‑up Between Two Proteins
The body sometimes mistakes a normal protein from the adenovirus for a human protein called platelet factor 4 (PF4). When this happens, the immune system makes antibodies that can trigger clotting.
How the Clotting Happens
These antibodies attach to PF4 and tell the blood to form a clot. The reaction is extremely rare, but understanding it gives scientists a clear target to fix.
What the Scientists Did
The team used powerful mass‑spectrometry tools to compare the adenovirus protein with PF4. They found a small piece of the virus protein that looks a lot like PF4 – a case of "molecular mimicry" that explains the mistaken attack.
Why This Matters
Now vaccine makers can change or remove that tiny virus protein piece (called pVII) from future adenovirus‑based shots. Doing so should keep the vaccines safe while still protecting people from disease.
Looking Ahead
Experts say this breakthrough is a big step toward safer vaccines, especially in places that rely on adenovirus carriers to stop infections.