Getting a human kidney on demand - imagine the smiles it would bring to millions of people who are waiting for a kidney transplant! Well, those days are not far away, thanks to the wonderful technology of 3-D printing.
3-D printing is nothing short of a revolution in the making. The Harvard School of Engineering and Applied Sciences ranked it among the first ten in breakthrough technologies that could change the world. No wonder, from developing a customized toothbrush, creating a real gun, and building a house in 24 hours to developing prosthetic limbs, human organ prototypes, and even tissue with blood vessels, 3-D printing, especially 3-D bio-printing is the latest buzzword in the research circles.
AdvertisementWhat is 3-D Printing?
3-D printing is a process of making three dimensional solid object from any digital object by using additive processing technology which involves creating and laying down successive layers of the material using a computer aided design (CAD) package or a 3D scanner.
Various additive processes are used in 3-D printing. Some of them are as follows:
Melting or softening material to produce sequential layering
Curing liquid material
Laminated object manufacturing where thin layers are cut to shape and joined together
These technologies use common materials such as metal alloys, for example, titanium alloys, stainless steel or materials like metal powders, ceramic powder, plaster, and even plastic films.
What makes 3-D printing interesting is its use in biomedical and tissue engineering. For example, surgeons used a type of flexible plastic to make windpipe splints for an American infant who had a condition that caused his windpipe to collapse. Similarly, in another case, titanium powder was used to create 3D printed lower jaw implant. These are examples of 3-D bioprinting.
3-D bio-printing and Tissue Engineering
3-D bio-printing is a type of 3-D printing that is used in health care industry and by medical researchers and bio-engineers. Basically, what researchers are doing here is they are trying to create a three-dimensional living tissue realistic enough to test drug efficacy.
They also want to take a step further to create fully functional tissue replacements and print it using 3-D bioprinters so that surgeons can use them to repair or replace damaged tissues and organs by a process called tissue engineering.
Surgeon Anthony Atala and his colleagues at Wake Forest Institute for Regenerative Medicine are working on regenerating and growing tissues and organs and currently they are developing a technology that can 'print' human tissue on demand. To make the tissue 'prints' functional, these tissues need a network of blood vessels to make them living, and of course making 3D prints of blood vessels is not an easy thing to do because the vascular system has to be provided with life sustaining oxygen and nutrients and also a way to remove carbon dioxide and waste material.
Bio-engineers have developed many 'bioprinters' and the most often used one is the 'inkjet inspired' printer in which cells are used like ink. Substances like hydrogel or collagen are used to hold the cells together. Harvard researchers have developed a kind of 'ink', one that melts as it cools. They first printed a network of interconnected filaments, then melted the material by chilling them and then suctioned the liquid out thus creating a network of vessels (tubes).
"Tissue engineers have been waiting for a method like this," said Don Ingber, Judah Folkman Professor of Vascular Biology and Professor of Bioengineering at Harvard and founding director of the Wyss Institute.
He believed that the ability to form functional 3D blood vessel networks before they are implanted will cause thicker tissues to be formed, and also greatly increase the chances of their engraftment and survival."
Reproducing cells through cell culture has been resorted to by scientists for years, but 3D printing gives the advantage of reducing the costs and offers an opportunity of printing an entire organ rather than just pieces.