3D-Printed Kidney Tissue Is Here

[iolaire]

http://motherboard.vice.com/read/3d-printed-kidney-tissue-is-here

3D-Printed Kidney Tissue Is Here

Written by Ben Richmond, Contributing Editor
April 2, 2015 // 04:00 AM EST

Just like you would hope, something very cool was revealed at the 2015 Experimental Biology conference in Boston: the biomedical company Organovo showed off its technique for 3D printing human kidney tissue.

Organovo has been working on printing functional human tissue since being incorporated in 2007, and first printed a cellular blood vessel in 2010. Since January 2014, it has offeredbioprintedliver tissue (marketed as exVive3D™ liver tissue) for companies to use in drug trials and disease modeling, and it looks as though its bioprinted human kidney tissue will be used for the same tasks, starting sometime in the latter half of 2016.

"Kidney represents an ideal extension of capabilities to 3D bioprint organ tissues that can be tremendously useful in pharmaceutical research," Keith Murphy, Organovo's chairman and CEO, said via press release. “The product that we intend to build from these initial results can be an excellent expansion for our core customers in toxicology, who regularly express to us an interest in having better solutions for the assessment of human kidney toxicity."

Organovo's website has a video that sort of explains how they take human cells and put them into, in this case, a matrix to grow into human tissue. An email with follow-up questions has yet to be answered, but as the Wall Street Journal explained in February, Organovo prints organs in much the same way, putting cells in as “bio-ink” and then printing them in layers, initially held together by hydrogel until the cells grow together.

The most common type of kidney cancer is renal cell carcinoma, so it's probably no surprise that Organovo demonstrated how it printed multiple “tissue-relevant cell types” to recapitulate the renal tubes themselves.

So far Organovo's 3D-printed liver tissue is used for preclinical drug trials, because the tissue responds like a real life human liver would for 42 days. That's much longer than the single layers of cells previously used in tests, which wilt in a few days. There are mixed views on how far off printing functional organs for transplant is. Growing tissue is one thing, but growing an organ and integrating it into a living body is another.

“Everybody’s dream is the 3D-printed organ. Are we ever going to get there?” asked Gabor Forgacs, whose research forms the basis of Organovo's method. “I’m not so sure,” he told the Select Biosciences Tissue Engineering & Bioprinting Conference, which was also held in Boston.

In the course of his keynote speech Forgacs argued that there was no reason functional organs couldn't be made eventually, but that printing replacement organs on demand was still decades away.

With the cost of bringing new drugs to market extremely high, and the price being passed on to consumers in dramatic and unfortunate ways, lowering the cost of pharmaceutical tests is still very useful. Like biopaper covered in collagen and a protein matrix, it’s a place to grow.

[PaulBC]

Thanks for posting this. I had heard about 3D printing organs, but never anything very specific. It sounds like the immediate application is for improving tissue cultures for testing. That's important, but a long way from making a new kidney.

“Everybody’s dream is the 3D-printed organ. Are we ever going to get there?” asked Gabor Forgacs, whose research forms the basis of Organovo's method. “I’m not so sure,” he told the Select Biosciences Tissue Engineering & Bioprinting Conference, which was also held in Boston.

I think Forgacs is projecting his own dreams, though I'd be happy with a way to make a new functioning kidney no matter how it's done. What I find strange about the emphasis on 3D printing is that it is so far from the way organs develop in the first place. Even something as complex as a nephron ultimately starts as an undifferentiated cell tissue that differentiates in place to form a complex structure. The granularity is not limited by the resolution of a device like a 3D printer, and the capability of forming this structure is inherent in the original cells. So I wonder if 3D printing is either necessary or sufficient to make new nephrons.

A better dream for me is figuring out how to get stem cells to repeat the embryonic development process themselves in a controlled environment and produce just the organ you want. There is also work on growing new kidneys using decellularized kidneys as scaffolds (either unusable human kidneys or pig kidneys). I am not sure it's very far along, but it sounds promising.

I can also see how there is a role for 3D printing here, not literally printing a nephron, but printing stem cells in a suitable 3D context to form one.

[iolaire]

It sounds like the immediate application is for improving tissue cultures for testing.

I'd  hope that by having the ability to quickly prototype cells for testing would be a big help on the research side.

[PaulBC]

I'd  hope that by having the ability to quickly prototype cells for testing would be a big help on the research side.

I agree. Hope I didn't sound like I was suggesting otherwise.

I just did a search on keywords printing a nephron (no quotes) and that came up with some other results. This one looked interesting. I think it's a completely different research team.

From MIT Technology Review

EmTech: 3-D Printing Complex Kidney Components
A breakthrough in printing blood vessels is enabling a new approach to printing organs.

By Kevin Bullis on September 24, 2014

(sidebar WHY IT MATTERS: Every day, 18 people die while waiting for an organ transplant.)

Earlier this year a group at Harvard solved one of the most difficult challenges involved in growing artificial human organs. The team used a 3-D printer to make human tissue that includes rudimentary blood vessels. Emboldened by that success, the researchers have started an ambitious project to make fully functioning printed kidneys.

Speaking at MIT Technology Review’s EmTech conference, Jennifer Lewis, professor of biologically inspired engineering at Harvard, said the ultimate goal—creating functioning human organs—is a “really long moon shot.” But she added that her group has made significant progress by fabricating rudimentary versions of structures in kidneys called nephrons. These artificial nephrons will allow drug companies to quickly screen potential medications, and they should help scientists understand kidneys at a more detailed level.

To produce tissues with blood vessels, Lewis’s group has invented novel 3-D printing inks and nozzles that allow it to precisely print multiple materials. For example, it can print various types of cells and materials that help connect cells. One of these inks allowed the group to make tunnels inside the tissues, which the researchers lined with blood vessel cells (see “Artificial Organs May Finally Get a Blood Supply”). Lewis said her group is using the same approach to making the tubes inside kidneys that help filter blood.

Lewis said the group chose to focus on kidneys because they account for 80 percent of the need for organ transplants, and because a large numbers of patients die before ever receiving a replacement kidney.

Other research groups have been printing thin sheet of cells—which grow to form functional tissues—for several years now (see “Printing Muscle”). But these efforts have been limited to making thin sheets; anything thicker than about half a millimeter means nutrients can’t get to the innermost cells, while waste can’t be evacuated. To make them thicker, and to eventually produce complete organs, researchers need to engineer a network of blood vessels.

Plenty of work remains, Lewis said—including integrating different cell types to make functional nephrons. Making complete organs will also require making more complex shapes and structures. For example, in kidneys you need to make blood vessels that branch into smaller ones—including capillaries so thin they’ll probably be beyond any existing printing technique.

[Rerun]

I don't really understand how 3D printing would work to create a new kidney... but I don't understand how my jet ink printer works either ...  and it doesn't half the time!