Using just a couple spoonfuls of blood, scientists have grown functioning blood vessels in a dish in just seven days. Amazingly, doctors then successfully transplanted the vascular grafts into three children for bypass procedures. Now that the safety and feasibility of this speedy procedure has been established, medics can start using the technique as a novel way to treat patients with vascular diseases across the globe, which affect some 25 million individuals worldwide. The report has been published in EBioMedicine.
Three years ago, Professor of Transplantation Biology Suchitra Sumitran-Holgersson and Surgeon Michael Olausson grew a new blood vessel for a patient who was missing a vein that connects the gastrointestinal tract to the liver. To do this, the duo first needed to get hold of some stem cells, so they drilled into her bone marrow and isolated them. Using the patient’s own cells is important because foreign cells can be rejected by the body’s immune system.
While the procedure was a success, it took a month to grow the personalized vessel, and extracting bone marrow is a particularly painful, unpleasant process. Thinking that they could do better, the duo decided to try out a new approach: extracting stem cells from blood samples. Just 25 milliliters of blood was taken from three children for this new trial, all of whom had the same condition as the woman that underwent the first procedure.
After isolating the necessary cells from the samples, the team used them to repopulate a vascular scaffold obtained from a donor that had been stripped of its cells. Remarkably, it took just one week to grow the personalized grafts using this technique. The speedy growth was actually assisted by the blood itself because it contains growth-promoting substances. They then transplanted the new veins into the children, which allowed the liver and GI tract to collaborate properly. Two of the children recovered and are still doing well, but the third is still under surveillance.
“We believe that this technological process can lead to dissemination of the method for the benefit of additional groups of patients, such as those with varicose veins or myocardial infarction, who need new blood vessels,” Sumitran-Holgersson said in a news-release. “Our dream is to be able to grow complete organs as a way of overcoming the current shortage from donors.”