More than a decade ago, Nicolas L’Hureux and Todd McCallister formed a company with the intent to create a human-derived alternative to synthetic blood vessels or grafts that are frequently used to treat dialysis patients. Their company, Cytograft Tissue Engineering Inc. (Novato, CA), announced in June of last year that it had succeeded in implanting lab-grown blood vessels made from skin cells from donors into three dialysis patients. At present, the company has announced that it has made the process of creating such human textiles less expensive, slashing the production costs in half.
In 2005, the company began creating vessels by extracting fibroblasts from patients’ skin, which were cultured into sheets and rolled up to fuse them together into a cylinder. While the vessels worked well in dialysis patients, it took about seven months to produce them. Following that, the company worked to make allogeneic vessels, grown from donor cells.
The company is now trying to combine the two approaches to “make something that is allogeneic, cheaper to produce, and that you could store forever, meaning that the clinician can pull it off the shelves whenever they want,” explains L’Heureux in a press release. “If it is frozen and allogeneic, that is kind of the homerun.”
The cost of creating vessels from donor cells is in the range of $6,000–$10,000 but it is expected to fall as automation technology progresses and volume increases. Nevertheless, the procedure still takes a matter of months to complete.
Consequently, the company decided to try a different approach: deconstruct sheets of cultured cells into threads, which can be used as textiles to form blood vessels. Although textiles are commonly used in medicine, they are generally synthetic. By contrast, the company is creating human textiles that haven’t been processed chemically. The textiles can be woven, knitted, or braided together into vessels in a couple of days. They also could help reduce the risk of infection as immune cells can interact with lab-grown biological tissue.
Though the technology is still in its infancy, the research has shown promise in animal trials, where the woven vessels have demonstrated resistance to being punctured. Ultimately, the technology could be used for a variety of applications ranging from treating congenital heart defects to improving outcomes of heart bypass surgery.