In a final experiment, scientists transplanted the new liver buds into mice with liver failure. The transplanted buds improved their survival, when compared to mice in liver failure that were subjected to sham surgeries.
Despite all these promising signs, researchers said they would continue to be on the lookout for two risks in future experiments -- cancer and transplant rejection.
In addition to developing into new kinds of organs and tissues, stem cells can also turn into tumors, a problem that's a constant worry in the field of regenerative medicine.
And because the organs were grown from cell lines taken from three different humans, they might be rejected by the immune system of the eventual host. For that reason, researchers think people who receive these kinds of lab-grown organs may still need anti-rejection drugs.
For more on stem cells, head to the U.S. National Institutes of Health.
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