Engineers Create Blood Vessels Woven From Human Tissue

Researchers say they have come up with a novel method to weave blood vessels from human tissue. 

In the new study, which appears in the April issue of The FASEB Journal, researchers show that they can make yarn by cutting sheets of a Cell Assembled Matrix (CAM) into ribbons that can be used directly or twisted into threads. They used these threads to weave blood vessels that displayed excellent mechanical properties without the need for any synthetic scaffolding or chemical treatments.

Blood vessel grafts made of woven synthetic polymer yarn are sometimes used to replace diseased arteries. However, the body recognizes the polymer as foreign and they are therefore prone to clot formation and blockages. By contrast, CAM is a biomaterial primarily made of human collagen - making it both biocompatible and mechanically strong.  In addition, they say the manufacturing method can be automated making it scalable, and affordable.

"It is time consuming and costly to get CAM layers to stick together," said the study's author Nicholas L'Heureux. "The new textile assembly approach is not only more versatile but also has the potential to be automated which would make it even faster, easier and cheaper to use."

L'Heureux also says it has many uses beyond just blood vessels, including jumpstarting the regeneration of many tissues and organs. So far it has been used to make lab-grown skin for burn patients and guides that help repair nerve injuries.

"Blood vessels are just one example of what can be done with our new textile approach to tissue engineering," said Nicolas L'Heureux.  "It can be used to make practically any shape by weaving, braiding or knitting the threads and allows very good control of the mechanical properties of the final product."

The researchers are now building additional blood vessel prototypes and learning more about the best ways to handle CAM threads and ribbons. They will soon start testing the vascular grafts in animals as a step toward eventual clinical trials in people.

L'Heureux was scheduled to present this research at the American Association for Anatomy annual meeting in San Diego this month. Though the meeting, to be held in conjunction with the 2020 Experimental Biology conference, was canceled in response to the COVID-19 outbreak, the research team's abstract was published in this month's issue of The FASEB Journal.

Cell‐assembled Extracellular Matrix (CAM) as a Biomaterial for Building Vascular Grafts
Nicolas L’Heureux
First published:20 April 2020 https://doi.org/10.1096/fasebj.2020.34.s1.00353