The 3D- bioprinter was covered in Dec, 2009, but there are more details about how the bioprinters work and the development path
Regenerative medicine is a rapidly advancing field that has the potential to transform human heath care. The potential now exists to develop tissue constructs for tissue repair and organ replacement. The US Dept. of Health and Human Services predicts that “within 20 years regenerative medicine will be the standard of care for replacing all tissue/organ systems in the body in addition to extensive industrial use for pharmaceutical testing.” Organovo, Inc. is dedicated to applying its breakthrough NovoGen tissue printing technology to make those goals a reality.
Dec 1, 2009 – Invetech, an innovator in new product development and custom automation for the biomedical, industrial and consumer markets, today announced that it has delivered the world’s first production model 3D bio-printer to Organovo, developers of the proprietary NovoGen bioprinting technology. Organovo will supply the units to research institutions investigating human tissue repair and organ replacement
The printer, developed by Invetech, fits inside a standard biosafety cabinet for sterile use. It includes two print heads, one for placing human cells, and the other for placing a hydrogel, scaffold, or support matrix. One of the most complex challenges in the development of the printer was being able to repeatedly position the capillary tip, attached to the print head, to within microns. This was essential to ensure that the cells are placed in exactly the right position. Invetech developed a computer controlled, laser-based calibration system to achieve the required repeatability.
Invetech plan to ship a number of 3D bio-printers to Organovo during 2010 and 2011 as a part of the instrument development program. Organovo will be placing the printers globally with researchers in centers of excellence for medical research
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.
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.