A freeze-dried blood product that could be stored for years on ambulances or in remote emergency departments is showing promise at treating traumatic brain injuries (TBIs).
In the study, scientists tested the product, called Thrombosomes, on blood vessel cells in petri dishes, in 3D organoid models of blood vessels and in mice after brain injury.
Mice given the product either one hour or one day after injury had less haemorrhage, less leakage from blood vessels and less brain inflammation, which can lead to swelling.
The work was carried out by researchers at UC San Francisco.
They said the product was originally developed to control bleeding in battlefield settings and is made from platelets that have been freeze-dried with a sugar called trehalose, which helps preserve some of their beneficial contents.
Unlike fresh platelets, which have a shelf life of about seven days, the freeze-dried product can reportedly be stored for up to five years.
Fresh platelets, which must be kept in refrigerators, are used to treat haemorrhage and some cancer patients and to prevent bleeding during surgery. But they have not been shown to be effective against TBI.
Researchers said scientists have only learned how to preserve platelets in the past 30 years, hoping to address an ongoing global shortage of fresh platelets, but no preserved platelet product has been approved for human use, let alone TBI.
The team also found the product contained high amounts of a protein that activates a receptor on blood vessel cells, helping to stabilise them. This may explain how the product makes them less leaky.
So far, that protein is the first of what the researchers said could be a cocktail of beneficial molecules.
“In some cases, surgeons will remove part of the skull to relieve the pressure, but there’s no drug that effectively treats swelling, or cerebral oedema, directly,” said Shibani Pati, director of the UCSF Center for Research Transfusion Medicine and Cell Therapies and senior author of the paper.
“We were excited to see how readily this product reinforced damaged blood vessels in the brain.
“Platelets carry many potent factors that go beyond clotting.
“In our mouse model of TBI, we saw hints that this product concentrates these factors, making it more effective than platelets themselves.”
The product is in phase II clinical trials for bleeding disorders, which means it has already been shown to be safe for people.
Researchers said this could hasten trials that test it for TBI.
