It's the next step on the path to robust tissue engineering and synthetic meat. Researchers today announced that they'd used special progenitor cells to grow human blood vessels inside mice. The vessels grew after scientists injected the cells into the mice, forming a "ball" of self-assembled veins that connected to each other and pumped blood.

The next steps could be transplanting these blood vessels, or using progenitor cells to grow vessels in engineered muscles or organs. According to the American Heart Association:

If researchers can develop ways to speed the growth of the vessels, non-surgical cardiac bypass procedures could potentially grow new vessels around those blocked by atherosclerosis.

[Lead researcher Joyce] Bischoff said other findings include:

* The cells created a vigorous network of vessels that connected to one another and to the vessels of the host mouse within seven days and continued to transport blood during the four-week study.

* Once combined and implanted, the two progenitor cells arranged themselves into vessels with minimal outside help, i.e., without any genetic alteration or manipulation to improve their growth. This is important because many growth-promoting genes are the same genes that become activated in cancer.

Eventually, predict researchers, Bischoff's technique could be used to treat cancer or heart disease. Imagine just regrowing an artery that had become clogged, or removing a tumor and replacing it with a chunk of tissue that already has healthy veins in it that can attach to your circulatory system.

Researchers Grow Human Blood Vessels in Mice [Eurekalert]

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