Human blood vessels grown in mouse offer hope to heart attack patients

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Human blood vessels grown in mouse offer hope to heart attack patients

By David Derbyshire
Last updated at 10:49 PM on 18th July 2008


Scientists have grown human blood vessels in a mouse for the first time using cells taken from an adult donor.

The breakthrough brings closer the day when heart disease patients will be able to grow replacement arteries from scratch.

The new vessels were created from a type of immature cell found in bone, blood and bone marrow and injected into the laboratory animals.

An X-ray showing the coronary arteries of the heart: The breakthrough could lead to the grafting of artificially grown vessels for heart disease patients

Eventually the same technique could be used to grow vessels directly in the human body.

"What's really significant about our study is that we are using human cells that can be obtained from blood or bone marrow rather than removing and using fully developed blood vessels," said Dr Joyce Bischoff, lead author of the study at Harvard Medical School and Children's Hospital Boston.

Past attempts to grow body parts have involved embryo stem cells - cells taken from newly conceived embryos which are capable of growing into any type of tissue, from brain to skin.

A laboratory rodent similar to the one used in the experiments to grow human blood vessels

But in the latest experiment, researchers used "progenitor cells" - which are found in adult's blood and bone marrow.

These are similar to stem cells, but can only develop into a limited range of tissue.

One type of cell used in the research develops into the cells that line blood vessels.

The other differentiates into cells that surround blood vessels and provide stability.

The cells were mixed in a culture dish with nutrients and growth factors and implanted into the cells of mice with weakened immune systems so that the vessels would not be rejected.

The cell mixture grew into a small ball of healthy blood vessels, the scientists report in Circulation Research: Journal of the American Heart Association.

Within seven days the network of vessels had connected to each other and the blood vessels of the mouse.

By using cells found in adult bodies to grow the blood vessels, the scientists say they can avoid the ethical dilemmas of using stem cells taken from embryos.

The technique could be used to increase the flow of blood to damaged organs - such as hearts after a heart attack.

Heart by-passes normally involve using a piece of vein to divert blood around a blocked section of coronary artery. But the grafts are difficult to find and have a high failure rate after 10 years.

Instead of taking arteries from a patient's leg, patients might be able to grow new arteries from scratch.

It could also speed up wound healing or by scientists trying to grow new organs for transplant in a laboratory.

One of the big obstacles to growing organs is forming enough blood vessels.

"What we are most interested in right now is speeding up the vascularization - the formation of blood vessels," said Dr Bischoff.

"We see very good and extensive vasculature in seven days and we'd like to see that in 24 or 48 hours."


Human blood vessels grown in mouse offer hope to heart attack patients | Mail Online