These creations could pave the way for human-sized organs for transplant.
Scientists working towards developing laboratory-grown livers for transplant have managed to create mini versions of the organ using a 3D printer.
Just half a millimetre deep and four millimetres wide, the tiny livers are capable of performing many critical functions of the real thing; including producing proteins responsible for ferrying hormones, salt and drugs around the body.
California-based bio-printing pioneers Organovo created the mini organs by using the machine to build up around 20 layers of liver cells – along with cells from the lining of blood vessels to nourish the liver cells with nutrients and oxygen.
The crucial addition of blood vessel cells means the 3D, multi-cellular tissue can survive for five days or more…
… Biotech company Organovo, a cutting edge firm with designs on changing the human landscape, says it has overcome the initial hurdles to creating a working human organ (in this case a liver) and will make it happen early next year.
With an enormous number of people on waiting lists for liver transplants in the U.S. alone, the announcement may well be the first step in a quest to change the very face of medicine as we know it.
Current organ transplant methodology is hampered by one enormous obstacle; the rejection of organ tissues transplanted from one patient to another, but all that could change if a patient’s own stem cells were used to build a working organ which would essentially be a custom outgrowth tailor made to those affected with organ failure.
Until now, size mattered. But Organovo say they’ve climbed that mountain and planted the company flag at the summit. Think of the problem this way: 3D printing the hepatocytes (cells which make up most liver tissue) is just the first step. To complete the picture, multiple types of cells, each with different functions and characteristics in tissue groups, all have to work together to create a living human organ, and it’s a complex process indeed. Researchers at Organovo say the key is that they’ve been able to combine tissues such as fibroblasts and endothelial cells which make up the minute vascular networks needed to supply an organ with blood.
Mike Renard, the Executive Vice President of Commercial Operations at Organovo, said it’s high precision – and the ability to stack and configure those precise layers of material – which made this latest discovery a true breakthrough.
“We’ve achieved thicknesses of greater than 500 microns, and have maintained liver tissue in a fully functional state with native phenotypic behavior for at least 40 days,” said Renard.
But it’s here that a dose of reality needs to be injected into the discussion. What Organovo has created is a liver tissue model which will be ready for use in 2014, and not a complete working human liver. The company says this initial “organ” will only be used for research in the laboratory and for medical studies and drug research.
Actually arriving at a human organ ready for use in patients would require extensive regulatory steps and reviews, including clinical trials and a review by the Food and Drug Administration which often takes anywhere from three to 10 years. All told, the entire process could well stretch out over a couple of decades.
“It’s too early to speculate on the breadth of applications that tissue engineering will ultimately deliver,” Renard said.
Manually growing thin skin tissue for use as temporary skin grafts is nothing new, but as 3D printing automates the construction of tissue via a syringe guided by a robotic mechanism and software, the process happens much more quickly. Organovo, using a proprietary bioprinting platform, have essentially automated creation of living human tissues capable of aping the functions of various tissues in the human body, and the process builds 3D human tissues “without dependence on biomaterial or scaffold components that would not be found in native tissues.”
No matter how you look at it, the technology and the processes at work are the next road signs marking the path to a “repeatable human.”