It is the stuff of science fiction: A patient is close to major
organ failure, and the doctors say death is imminent without an
immediate transplant. Strangely, though, nobody seems particularly
perturbed. The reason is simple: Early that morning, they had taken a
cell sample from the patient, and now a new organ, produced on a
state-of-the-art medical 3D printer, is ready for transplanting. A few
days after the transplant operation, the patient leaves the hospital
feeling like a new person. That scenario is still a long way off, but is
probably not as far away as many people imagine.
3D printers are used to make a growing range of solid objects including aircraft parts, children's toys, prototype models, plastic bicycles, false teeth, and cosmetics. The machines print individual objects in fine successive layers one on top of the other by processes like additive layer manufacturing and sintering. Engineers have devised many variations of these general processes in order to print objects of different qualities from a wide variety of materials including metals, plastics, ceramics, plaster, and polymer. 3D printers have also been used in medicine to produce items like prosthetic limbs and joints. Recent technological advances promise to broaden those medical uses to include processes never before thought possible.
For example, San Diego company Organovo, is working to transform the use of 3D printers in the field of pharmaceutical trials. In a process called bioprinting, the company's computer-controlled printers build living body tissue one layer at a time like in a standard 3D process. Each of the special printers has two "ink" hoppers and two pipette type print heads. One printer hopper is filled with a milky solution of living cells, and the second contains a gel. The print heads deposit the cell solution and the gel simultaneously. The gel helps the cell aggregate hold the desired shape - a process that normally takes a few hours. After that time, the gel is dissolved away. The company has experimented with tissue for different organs and has already successfully printed slivers of heart, kidney, and lung tissue.
These developments are of particular value to pharmaceutical companies. Initial research indicates that 3D printed tissue responds to drugs in the same way as living organs inside the body do. So, the pharmaceutical companies can use 3D printed tissue to test the efficacy and toxicity of new drugs quickly at a fraction of the costs of using live subjects and without the risk of dangerous side effects.
Producing a small slice of living tissue with a 3D printer is a huge achievement, but the longer-term goal of many scientists is to produce complete organs using these printing techniques. That would have two major advantages over the current situation. First, a much more reliable method for obtaining replacement organs would exist. Second, those organs could be made from cultures of patients' own cells, and so would not be rejected by the immune systems. However, producing a complex organ like a liver or heart with an entire vascular system of large vessels branching to ever-smaller ones on a 3D printer, or indeed by any other means, presents a far greater challenge than producing a small sliver of tissue.
Scientists are approaching the problems from different directions and achieving promising results. Some are working on methods to create blood vessels by making hollow tubes from protein and fat cells that can "trap" endothelial cells - the cells that form blood vessels. These tubes form a sort of scaffold in which the blood vessels can grow. Other scientists are working on 3D printers that print cells directly onto skin - an application especially useful for treating burns and other surface wounds. A laser scans the wound to determine its exact dimensions; the printer then deposits the precise amount of living tissue to match those dimensions.
The future of 3D printing in medicine is exciting. It cannot quite match up to the ideas of science fiction writers because science fiction is, by definition, about what has yet to happen. Nevertheless, science fiction plays a vital part because all great scientific advances started life as fiction. The world has always needed visionaries and dreamers, whether writers or scientists, to move it forward. Luckily, there is no shortage of those creative thinkers today.
Article Source:
http://EzineArticles.com/?expert=Raphael_Huppe
3D printers are used to make a growing range of solid objects including aircraft parts, children's toys, prototype models, plastic bicycles, false teeth, and cosmetics. The machines print individual objects in fine successive layers one on top of the other by processes like additive layer manufacturing and sintering. Engineers have devised many variations of these general processes in order to print objects of different qualities from a wide variety of materials including metals, plastics, ceramics, plaster, and polymer. 3D printers have also been used in medicine to produce items like prosthetic limbs and joints. Recent technological advances promise to broaden those medical uses to include processes never before thought possible.
For example, San Diego company Organovo, is working to transform the use of 3D printers in the field of pharmaceutical trials. In a process called bioprinting, the company's computer-controlled printers build living body tissue one layer at a time like in a standard 3D process. Each of the special printers has two "ink" hoppers and two pipette type print heads. One printer hopper is filled with a milky solution of living cells, and the second contains a gel. The print heads deposit the cell solution and the gel simultaneously. The gel helps the cell aggregate hold the desired shape - a process that normally takes a few hours. After that time, the gel is dissolved away. The company has experimented with tissue for different organs and has already successfully printed slivers of heart, kidney, and lung tissue.
These developments are of particular value to pharmaceutical companies. Initial research indicates that 3D printed tissue responds to drugs in the same way as living organs inside the body do. So, the pharmaceutical companies can use 3D printed tissue to test the efficacy and toxicity of new drugs quickly at a fraction of the costs of using live subjects and without the risk of dangerous side effects.
Producing a small slice of living tissue with a 3D printer is a huge achievement, but the longer-term goal of many scientists is to produce complete organs using these printing techniques. That would have two major advantages over the current situation. First, a much more reliable method for obtaining replacement organs would exist. Second, those organs could be made from cultures of patients' own cells, and so would not be rejected by the immune systems. However, producing a complex organ like a liver or heart with an entire vascular system of large vessels branching to ever-smaller ones on a 3D printer, or indeed by any other means, presents a far greater challenge than producing a small sliver of tissue.
Scientists are approaching the problems from different directions and achieving promising results. Some are working on methods to create blood vessels by making hollow tubes from protein and fat cells that can "trap" endothelial cells - the cells that form blood vessels. These tubes form a sort of scaffold in which the blood vessels can grow. Other scientists are working on 3D printers that print cells directly onto skin - an application especially useful for treating burns and other surface wounds. A laser scans the wound to determine its exact dimensions; the printer then deposits the precise amount of living tissue to match those dimensions.
The future of 3D printing in medicine is exciting. It cannot quite match up to the ideas of science fiction writers because science fiction is, by definition, about what has yet to happen. Nevertheless, science fiction plays a vital part because all great scientific advances started life as fiction. The world has always needed visionaries and dreamers, whether writers or scientists, to move it forward. Luckily, there is no shortage of those creative thinkers today.
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