A machine that prints organs is coming to market
« on: 2010-03-04 22:19:19 »
So print/grow your own replacement parts .... "would you like that supersized sir" :-)
Source: The Economist Author: From The Economist print edition Date: Feb 18th 2010
Making a bit of me
Illustration by David Simonds
THE great hope of transplant surgeons is that they will, one day, be able to order replacement body parts on demand. At the moment, a patient may wait months, sometimes years, for an organ from a suitable donor. During that time his condition may worsen. He may even die. The ability to make organs as they are needed would not only relieve suffering but also save lives. And that possibility may be closer with the arrival of the first commercial 3D bio-printer for manufacturing human tissue and organs.
The new machine, which costs around $200,000, has been developed by Organovo, a company in San Diego that specialises in regenerative medicine, and Invetech, an engineering and automation firm in Melbourne, Australia. One of Organovo’s founders, Gabor Forgacs of the University of Missouri, developed the prototype on which the new 3D bio-printer is based. The first production models will soon be delivered to research groups which, like Dr Forgacs’s, are studying ways to produce tissue and organs for repair and replacement. At present much of this work is done by hand or by adapting existing instruments and devices.
To start with, only simple tissues, such as skin, muscle and short stretches of blood vessels, will be made, says Keith Murphy, Organovo’s chief executive, and these will be for research purposes. Mr Murphy says, however, that the company expects that within five years, once clinical trials are complete, the printers will produce blood vessels for use as grafts in bypass surgery. With more research it should be possible to produce bigger, more complex body parts. Because the machines have the ability to make branched tubes, the technology could, for example, be used to create the networks of blood vessels needed to sustain larger printed organs, like kidneys, livers and hearts. Printing history
Organovo’s 3D bio-printer works in a similar way to some rapid-prototyping machines used in industry to make parts and mechanically functioning models. These work like inkjet printers, but with a third dimension. Such printers deposit droplets of polymer which fuse together to form a structure. With each pass of the printing heads, the base on which the object is being made moves down a notch. In this way, little by little, the object takes shape. Voids in the structure and complex shapes are supported by printing a “scaffold” of water-soluble material. Once the object is complete, the scaffold is washed away.
Researchers have found that something similar can be done with biological materials. When small clusters of cells are placed next to each other they flow together, fuse and organise themselves. Various techniques are being explored to condition the cells to mature into functioning body parts—for example, “exercising” incipient muscles using small machines.
Though printing organs is new, growing them from scratch on scaffolds has already been done successfully. In 2006 Anthony Atala and his colleagues at the Wake Forest Institute for Regenerative Medicine in North Carolina made new bladders for seven patients. These are still working.
Dr Atala’s process starts by taking a tiny sample of tissue from the patient’s own bladder (so that the organ that is grown from it will not be rejected by his immune system). From this he extracts precursor cells that can go on to form the muscle on the outside of the bladder and the specialised cells within it. When more of these cells have been cultured in the laboratory, they are painted onto a biodegradable bladder-shaped scaffold which is warmed to body temperature. The cells then mature and multiply. Six to eight weeks later, the bladder is ready to be put into the patient.
The advantage of using a bioprinter is that it eliminates the need for a scaffold, so Dr Atala, too, is experimenting with inkjet technology. The Organovo machine uses stem cells extracted from adult bone marrow and fat as the precursors. These cells can be coaxed into differentiating into many other types of cells by the application of appropriate growth factors. The cells are formed into droplets 100-500 microns in diameter and containing 10,000-30,000 cells each. The droplets retain their shape well and pass easily through the inkjet printing process.
A second printing head is used to deposit scaffolding—a sugar-based hydrogel. This does not interfere with the cells or stick to them. Once the printing is complete, the structure is left for a day or two, to allow the droplets to fuse together. For tubular structures, such as blood vessels, the hydrogel is printed in the centre and around the outside of the ring of each cross-section before the cells are added. When the part has matured, the hydrogel is peeled away from the outside and pulled from the centre like a piece of string.
The bio-printers are also capable of using other types of cells and support materials. They could be employed, Mr Murphy suggests, to place liver cells on a pre-built, liver-shaped scaffold or to form layers of lining and connective tissue that would grow into a tooth. The printer fits inside a standard laboratory biosafety cabinet, for sterile operation. Invetech has developed a laser-based calibration system to ensure that both print heads deposit their materials accurately, and a computer-graphics system allows cross-sections of body parts to be designed.
Some researchers think machines like this may one day be capable of printing tissues and organs directly into the body. Indeed, Dr Atala is working on one that would scan the contours of the part of a body where a skin graft was needed and then print skin onto it. As for bigger body parts, Dr Forgacs thinks they may take many different forms, at least initially. A man-made biological substitute for a kidney, for instance, need not look like a real one or contain all its features in order to clean waste products from the bloodstream. Those waiting for transplants are unlikely to worry too much about what replacement body parts look like, so long as they work and make them better.
How a new manufacturing technology will change the world Technology
THE industrial revolution of the late 18th century made possible the mass production of goods, thereby creating economies of scale which changed the economy—and society—in ways that nobody could have imagined at the time. Now a new manufacturing technology has emerged which does the opposite. Three-dimensional printing makes it as cheap to create single items as it is to produce thousands and thus undermines economies of scale. It may have as profound an impact on the world as the coming of the factory did.
It works like this. First you call up a blueprint on your computer screen and tinker with its shape and colour where necessary. Then you press print. A machine nearby whirrs into life and builds up the object gradually, either by depositing material from a nozzle, or by selectively solidifying a thin layer of plastic or metal dust using tiny drops of glue or a tightly focused beam. Products are thus built up by progressively adding material, one layer at a time: hence the technology’s other name, additive manufacturing. Eventually the object in question—a spare part for your car, a lampshade, a violin—pops out. The beauty of the technology is that it does not need to happen in a factory. Small items can be made by a machine like a desktop printer, in the corner of an office, a shop or even a house; big items—bicycle frames, panels for cars, aircraft parts—need a larger machine, and a bit more space.
At the moment the process is possible only with certain materials (plastics, resins and metals) and with a precision of around a tenth of a millimetre. As with computing in the late 1970s, it is currently the preserve of hobbyists and workers in a few academic and industrial niches. But like computing before it, 3D printing is spreading fast as the technology improves and costs fall. A basic 3D printer, also known as a fabricator or “fabber”, now costs less than a laser printer did in 1985.
Just press print
The additive approach to manufacturing has several big advantages over the conventional one. It cuts costs by getting rid of production lines. It reduces waste enormously, requiring as little as one-tenth of the amount of material. It allows the creation of parts in shapes that conventional techniques cannot achieve, resulting in new, much more efficient designs in aircraft wings or heat exchangers, for example. It enables the production of a single item quickly and cheaply—and then another one after the design has been refined.
For many years 3D printers were used in this way for prototyping, mainly in the aerospace, medical and automotive industries. Once a design was finalised, a production line would be set up and parts would be manufactured and assembled using conventional methods. But 3D printing has now improved to the point that it is starting to be used to produce the finished items themselves (see article). It is already competitive with plastic injection-moulding for runs of around 1,000 items, and this figure will rise as the technology matures. And because each item is created individually, rather than from a single mould, each can be made slightly differently at almost no extra cost. Mass production could, in short, give way to mass customisation for all kinds of products, from shoes to spectacles to kitchenware.
By reducing the barriers to entry for manufacturing, 3D printing should also promote innovation. If you can design a shape on a computer, you can turn it into an object. You can print a dozen, see if there is a market for them, and print 50 more if there is, modifying the design using feedback from early users. This will be a boon to inventors and start-ups, because trying out new products will become less risky and expensive. And just as open-source programmers collaborate by sharing software code, engineers are already starting to collaborate on open-source designs for objects and hardware.
The jobless technology
A technological change so profound will reset the economics of manufacturing. Some believe it will decentralise the business completely, reversing the urbanisation that accompanies industrialisation. There will be no need for factories, goes the logic, when every village has a fabricator that can produce items when needed. Up to a point, perhaps. But the economic and social benefits of cities (see article) go far beyond their ability to attract workers to man assembly lines.
Others maintain that, by reducing the need for factory workers, 3D printing will undermine the advantage of low-cost, low-wage countries and thus repatriate manufacturing capacity to the rich world. It might; but Asian manufacturers are just as well placed as anyone else to adopt the technology. And even if 3D printing does bring manufacturing back to developed countries, it may not create many jobs, since it is less labour-intensive than standard manufacturing. Our TQ article explains the technology behind the 3-D printing process
The technology will have implications not just for the distribution of capital and jobs, but also for intellectual-property (IP) rules. When objects can be described in a digital file, they become much easier to copy and distribute—and, of course, to pirate. Just ask the music industry. When the blueprints for a new toy, or a designer shoe, escape onto the internet, the chances that the owner of the IP will lose out are greater.
There are sure to be calls for restrictions on the use of 3D printers, and lawsuits about how existing IP laws should be applied. As with open-source software, new non-commercial models will emerge. It is unclear whether 3D printing requires existing rules to be tightened (which could hamper innovation) or loosened (which could encourage piracy). The lawyers are, no doubt, rubbing their hands.
Just as nobody could have predicted the impact of the steam engine in 1750—or the printing press in 1450, or the transistor in 1950—it is impossible to foresee the long-term impact of 3D printing. But the technology is coming, and it is likely to disrupt every field it touches. Companies, regulators and entrepreneurs should start thinking about it now. One thing, at least, seems clear: although 3D printing will create winners and losers in the short term, in the long run it will expand the realm of industry—and imagination.