Three-layer skeletons of blood vessels from a 3D printer
Biotechnologists have printed full-fledged blood vessels for the first time
Currently, the patient's own vessels extracted from other parts of the body, such as the legs, are used for this purpose. However, it often turns out that the patient does not have his own vessels suitable for surgery. Waiting for a donor and preparing for a surgical procedure can take almost a year. At the same time, the use of donor material is often accompanied by rejection of transplanted tissues, which requires additional efforts to suppress the response of the immune system.
In recent years, scientists have created several prototypes of artificial or partially artificial vessels that temporarily replace damaged arteries and capillaries until the body grows new blood flows. For example, in February 2011, American biologists learned how to grow "skeletons" for future vessels from collagen and successfully transplanted them into the body of baboons and dogs.
The main problem of all such vessels, notes Yuanyuan Liu from Shanghai University (China) and his colleagues, are two things – low resistance to mechanical loads and low rate of "overgrowth" by cells of real vessels. Chinese biotechnologists solved this problem using a special printer that allowed them to assemble accurate three-dimensional copies of vessels from three layers.
A three-dimensional frame, ready to be populated with cells and turned into a full-fledged vessel.
A snapshot from an article in AIP Advances – VM
Each of these layers is responsible for its own function – for example, the middle layer of PDS polymer molecules is responsible for mechanical resistance, and their outer and inner coating, which is a set of polyvinyl and chitosan filaments, helps the cells of future vessels cling to the surface of their artificial counterpart.
As the researchers emphasize, such vessels cannot yet be found in clinics – they have to go through the stages of clinical trials on animals and humans before they are approved by the medical services of the world. In the near future, Liu and his colleagues plan to implant an artificial vessel into the body of a rat to check how quickly it will overgrow with new tissue.
Portal "Eternal youth" http://vechnayamolodost.ru05.02.2015