Printer Created Blood Vessels Gives Hope to Transplant Patients
14 Sep, 2011 - 09:37pm
In Germany alone, an estimated 11,000 people at the beginning of the year were awaiting a transplant. Sadly, less than half of those on the transplant waiting list will be able to receive a transplant this year. This demand for organ transplants only seemingly continues to grow, and while science has been attempting to create artificial organs for years, they have not yet been able to successfully do so.
New research that has come out of Fraunhofer reveals that there are a number of new techniques and materials now available which have led to the creation of artificial blood vessels. This was part of the BioRap project, and will be exhibited at the Biotechnica Fair in Hannover, Germany from October 11 to the 13th.
Leading the way for this successful research were five Fraunhofer institutes which joined up in 2009 with one goal: to come up with a biocompatible artificial blood vessel. The first stumbling block was about just how they were going to build such complex and small structures, but the production engineering team were able to help build even the most complex of vessels, such as capillary vessels, using a 3D model.
Once a 3D model was available, the Fraunhofer researchers were able to use both that and multiphoton polymerization to go ahead and begin creating artificial blood vessels. The combination of the two turned out to be a wonderful success. A 3D inkjet printer can quickly create 3D solids from a wide choice of materials. The different layers of material are all bonded with UV radiation. The two-photon polymerization is then used in conjunction with the 3D printed models to create more complex structures, as well as give it a more stretchy and elastic body. This is particularly important as the vessels must be elastic in order to interact with natural tissues.
So that living body cells can “dock” onto these synthetic tubes, they are biofunctionalized. Scientists take modified biomolecules, such as anchor peptides and heparin, and then integrate them into the inside walls of the vessels. Inks have also been developed that contain a mixture of biomolecules and synthetic polymers right from the start of the vessel’s creation.
The other challenge that the researchers are looking at is ensuring that the lining in the artificial vessels works in the same way as real vessels. Blood must not stick to the walls, and must still be transported onwards so that nutrients can be distributed throughout the body.
Dr. Guntar Tovar, the project manager at the Fraunhofer Institute for interfacial Engineering and Biotechnology IGB based in Stuttgart, says, “We are establishing a basis for applying rapid prototyping to elastic and organic biomaterials. The vascular systems illustrate very dramatically what opportunities this technology has to offer, but that’s definitely not the only thing possible.”
Heart Disease is the leading cause of morbidity across the world and currently complex organs have not been able to be successfully recreated for transplant patients, but the hope is that all artificial organs which are based on a circulation system with blood vessels will soon be suitable for transplants. Another hope is that the artificial vessels will be able to help treat bypass patients. Artificial organs that replicate human organs can also be used for laboratory testing rather than less-accurate animal testing.