PRINT RIGHT onto the PATIENT
Next Step in 3D Printing: Your Kidneys
by Anya Kamenetz / Mar 3, 2011
Dr. Anthony Atala, a regenerative medicine specialist at Wake Forest University, is pioneering the use of printing techniques to reconstruct and repair human flesh and organs. The basis is a combination of cultured human cells and scaffolding built or woven from organic material. In one staggering setup, a patient lies on a table and a flatbed scanner literally scans her wound, followed by a printer that adds just the right types of tissues back on at the right depth. “You can print right on the patient,” Dr. Atala told the TED audience on Thursday. “I know it sounds funny, but it’s true.” The next evolving step is the use of 3-D printers, which I wrote about on Tuesday, to rebuild human organs. Ninety percent of patients on the organ donation list are waiting for kidneys, a fist-size organ with a profusion of tiny blood vessels. To build a customized kidney, first you scan the patient with a CT scanner, then use 3D imaging techniques to create a computerized form that the printer can read, and finally build the organ layer by layer. Printing a new kidney takes about six hours, and it lasts for a lifetime–a young man came out on stage who had the surgery in the early days, 10 years ago.
EZ BAKE ORGANS
Surgeon Creates New Kidney Onstage / March 4, 2011
“It’s like baking a cake,” Anthony Atala of the Wake Forest Institute of Regenerative Medicine said as he cooked up a fresh kidney on stage at a TED Conference in the California city of Long Beach. Scanners are used to take a 3-D image of a kidney that needs replacing, then a tissue sample about half the size of postage stamp is used to seed the computerized process, Atala explained. The organ “printer” then works layer-by-layer to build a replacement kidney replicating the patient’s tissue. College student Luke Massella was among the first people to receive a printed kidney during experimental research a decade ago when he was just 10 years old. He said he was born with Spina Bifida and his kidneys were not working. “Now, I’m in college and basically trying to live life like a normal kid,” said Massella, who was reunited with Atala at TED “This surgery saved my life and made me who I am today.” About 90 percent of people waiting for transplants are in need of kidneys, and the need far outweighs the supply of donated organs, according to Atala. “There is a major health crisis today in terms of the shortage of organs,” Atala said. “Medicine has done a much better job of making us live longer, and as we age our organs don’t last.”
New Device Prints Human Tissue
by Bill Christensen / 29 December 2009
Invetech has delivered what it calls the “world`s first production model 3D bio-printer” to Organovo, developers of the proprietary NovoGen bioprinting technology. Organovo will in turn supply the devices to institutions investigating human tissue repair and organ replacement. Keith Murphy, CEO of Organovo, based in San Diego, said the units represent a breakthrough because they provide for the first time a flexible technology platform for organizations working on many different types of tissue construction and organ replacement. “Scientists and engineers can use the 3D bio printers to enable placing cells of almost any type into a desired pattern in 3D,” Murphy said. “Researchers can place liver cells on a preformed scaffold, support kidney cells with a co-printed scaffold, or form adjacent layers of epithelial and stromal soft tissue that grow into a mature tooth. Ultimately the idea would be for surgeons to have tissue on demand for various uses, and the best way to do that is get a number of bio-printers into the hands of researchers and give them the ability to make three dimensional tissues on demand.”
The 3D bio-printers include an intuitive software interface that allows engineers to build a model of the tissue construct before the printer commences the physical constructions of the organs cell-by-cell using automated, laser-calibrated print heads. “Building human organs cell-by-cell was considered science fiction not that long ago,” said Fred Davis, president of Invetech, which has offices in San Diego and Melbourne. “Through this clever combination of technology and science we have helped Organovo develop an instrument that will improve people’s lives, making the regenerative medicine that Organovo provides accessible to people around the world.” Science fiction, indeed. Artificial organs have been a science fiction staple since writer Philip K. Dick wrote about artiforgs (artificial organs) in his 1964 novel Cantata 140 and Larry Niven’sartificially grown organs in his 1968 novel A Gift From Earth.
SIR, YOUR LIVER is READY
Behind the Scenes of Bioprinting
by By Dave Bullock / July 11, 2010
Say goodbye to donor lists and organ shortages. A biotech firm has created a printer that prints veins using a patients’ own cells. The device could potentially create whole organs in the future. “Right now we’re really good at printing blood vessels,” says Ben Shepherd, senior research scientist at regenerative-medicine company Organovo. “We printed 10 this week. We’re still learning how to best condition them to be good, strong blood vessels.” Most organs in the body are filled with veins, so the ability to print vascular tissue is a critical building block for complete organs. The printed veins are about to start testing in animal trials, and eventually go through human clinical trials. If all goes well, in a few years you may be able to replace a vein that has deteriorated (due to frequent injections of chemo treatment, for example) with custom-printed tissue grown from your own cells. The barriers to full-organ printing are not just technological. The first organ-printing machine will cost hundreds of millions of dollars to develop, test, produce and market. Not to mention the difficulty any company will have getting FDA approval. “If Organovo will be able to raise enough money this company has [the] potential to succeed as [the] first bioprinting company but only time will show,” says Dr. Vladimir Mironov, director of advanced tissue biofabrication at the Medical University of South Carolina. Organovo walked Wired.com through the process it uses to print blood vessels on the custom bioprinter.
Shepherd places a bioreactor inside an incubator where it will be pumped with a growth medium for a few days. The bioreactor uses a special mixture of chemicals that are similar to what cells would see when they grow inside the body, which will help the cells become strong vascular tissue.
Senior research scientist Ben Shepherd removes stem cells from a bath of liquid nitrogen. The cells will be cultured to greatly increase their number before being loaded into the printer. Eventually these cells could be taken from a variety of places in a patient’s body –- fat, bone marrow and skin cells –- and made into a working vein.
After the cells are defrosted they are cultured in a growth medium (above). This allows the cells to multiply and grow so they can be used to form veins. The medium also uses special chemicals to tell the stem cells to grow into the cell type required, in this case blood-vessel cells. Once a enough cells are produced, they are separated from the growth medium using a centrifuge (below) and compressed into pellets.
photos: Dave Bullock/Wired.com
The first step of the printing process is to lay down a material called hydrogel, which is used as a temporary scaffolding to support the vein tissue. The custom-made printer uses two pump heads that squirt out either the scaffolding structure or the cells into a petri dish. The pump heads are mounted on a precision robotic assembly for microscopic accuracy. The head on the right is dipping into the container of hydorogel in the photo above.
A chamber called a bioreactor is used to stimulate the vein. It’s prepared before the vein is printed. The bioreactor is a fairly standard piece of biotech machinery. It is machined out of a block of aluminum that surrounds a plastic container with various ports. These ports are used to pump in chemicals that will feed the growing vein.
Before printing the veins, tubes of the cultured cells are loaded into the print head manually, like a biomass print cartridge.
Hydrogel Mold for Blood Vessels
Lines of the hydrogel are laid down in parallel in a trough shape on the petri dish. Then cylinders of cell pellets are printed into the trough. One more cylinder of hydrogel is printed into the middle of the cells, which serves to create the hole inside the vein where blood will eventually flow (below).
Illustration courtesy Organovo
Growing Into Veins
The printed veins are then left in a different growth medium for several weeks. The cells soon release from the hydrogel, and a hollow tube of vascular cells is left behind.
The printed cells in tubular form are then placed into the bioreactor. The bioreactor (above) pumps a special cocktail of proteins, buffers and various other chemicals (below) through the printed vein. This conditions the cells to be good, strong veins and keep them happy.
After their stay in the bioreactor, the pellets of cells grow together to form veins which can then be implanted in the patient. Because the veins are grown from the patient’s own cells, their body is more likely to accept the implanted vein.