Researchers have achieved a breakthrough in growing functional human blood vessels in mice using cells from adult human donors. The achievement is seen as an important step in developing clinical strategies to grow tissue vessels that may one day deliver oxygen-rich blood to damaged organs.

Researchers withdrew stem cells from the blood or bone marrow of adults or the umbilical cord blood of newborns. The cells were combined with two different types of progenitor cells in a culture dish of nutrients and growth factors. The cells were then implanted into mice with weakened immune systems.

Once implanted, the progenitor cell mixture grew and differentiated into a small ball of healthy blood vessels, researchers report in the Circulation research journal.

If the experiment proves successful in humans, it could pave the way to repair blood-deprived regions of organs that have been damaged by heart attacks or other conditions that impair circulation, according to researchers.