In March, researchers at the Roslin Institute in Scotland reported they had managed to grow stem cells without directly exposing the stem cells to animal cells, though the stem cells were still indirectly exposed to animal cells.
Until now, embryonic stem cells are grown using mouse feeder cells and in animal growth serum. There is some concern that as long as animal cells are used in the process that there is a risk that an animal virus will be transmitted to human beings who might someday receive stem cell transplants.
The Roslin Institute researchers used human protein laminin and feeder cells taken from human neonatal foreskin cells to provide the nutrients that the embryonic stem cells need.
This process is still not entirely animal-free, however, as the neonatal human foreskin cells are themselves grown in a process which uses animal cells.
Almost certainly at some point embryonic stem cells will be grown end to end in non-animal substrates at which point the animal rights movement will claim that animal research had nothing at all to do with embryonic stem cell research.
Sources:
Human embryonic stem cells grown animal-free. Andy Coghlan, New Scientist, March 17, 2005.
‘Animal free’ stem cells created. The BBC, March 16, 2005.