This machine is weaving 48 strands of human connective tissue together into a tube.
Growing fresh blood vessels is a much fantasized-about goal of biomedical engineers. It sounds vaguely vampiric, but the idea is to replace the veins in the arms of dialysis patients
, which are a mess from being breached several times a week to be hooked up to a blood-cleaning machine. From there, engineers hope to provide off-the-shelf replacements for heart valves and such. Most approaches involve getting human cells---either donor cells or cells from the patient---to manufacture rubbery connective tissue
made of proteins, from which the cells are stripped away to avoid an immune reaction in patients. Some companies start with flat sheets of this tissue and roll them into tubes, while others have the cells make the stuff around a tubular mold
. One company, though, is trying out a technique that made us look twice. They're weaving the vessels from thread spun with thin strips of cultured connective tissue
, Technology Review reports. The hope is that given manufacturers' copious experience with machine weaving, these woven structures could be easier to mass-produce than the tubes made with other techniques. Though there isn't much information publicly available yet on how Cytograft
, as the company is called, is making the vessels, the company told Tech Review that early tests in dogs have shown that blood doesn't leak out from the weave much and the structures stand up to regular puncturing, a must if they are to replace the veins of dialysis patients. Image courtesy of Cytograft