The NHS and University of Cambridge team have discovered how to grow the body's platelet factories in the laboratory.
It could provide a new source of platelets to stop heavy bleeding, for example after a car crash.
But the researchers need to make the process more efficient before starting trials.
If you donate blood, then it is separated out into red blood cells, plasma and platelets so patients are given only the component they need.
Platelets are needed after trauma, surgery, leukaemia therapy and in some blood disorders like haemophilia.
"We're totally dependent on blood donation to produce those platelets," said Dr Cedric Ghevaert, a consultant haematologist.
Huge leap to mass produced platelets BBC News