The Next Frontier for 3-D Printing: Human Organs

Scientists are on their way to 3-D printing functioning large organs. In the meantime, the technology is being used to test drug responses in mini-systems.

A 3D printer constructs a model human figure in the exhibition '3D: printing the future' in the Science Museum on October 8, 2013 in London, England.
National Journal
Sophie Novack
Add to Briefcase
See more stories about...
Sophie Novack
Dec. 27, 2013, midnight

Re­search­ers at Wake Forest Baptist Med­ic­al Cen­ter are em­bark­ing on a pro­ject that is so over­loaded with sci-fiesque ele­ments that if it were a movie, you might ques­tion the screen­writer’s cred­ib­il­ity.

The “body on a chip” pro­ject will use 3-D print­ing — or bioprint­ing — tech­no­logy to cre­ate mini hu­man-or­gan sys­tems about the size of a quarter to test the body’s re­sponse to drugs. It’s fun­ded by a $24 mil­lion grant from the De­fense De­part­ment to de­vel­op an­ti­dotes to very strong agents in the areas of chem­ic­al and bio­lo­gic­al war­fare.

The ul­ti­mate goal of bioprint­ing is to cre­ate large, func­tion­al, im­plant­able or­gans that will ad­dress the grow­ing gap between vi­able or­gan sup­ply and de­mand for trans­plants. Along the way, the sim­pler, mini-ver­sions can be used to more ef­fect­ively test drugs.

A few groups have been ex­per­i­ment­ing with bioprint­ing tis­sues and or­gans, but the body-on-a-chip pro­ject is unique in con­nect­ing the struc­tures to­geth­er. The chip will be able to test the im­pact of agents — in­clud­ing in­tense chem­ic­al weapons, more main­stream drugs, and treat­ments — on the hu­man body. The pro­ject of­fers an al­tern­at­ive to an­im­al test­ing — which is of­ten in­ef­fi­cient and in­ac­cur­ate for meas­ur­ing hu­man re­sponses — and en­ables the lab to test the full sys­tem’s re­sponse, rather than just one type of or­gan.

Sci­ent­ists star­ted mak­ing tis­sues by hand about 25 years ago. Us­ing a tech­nique known as scaf­fold­ing, cells from a pa­tient’s tis­sue were layered on 3-D molds and grown in an in­cub­at­or out­side the body. Us­ing bioprint­ing tech­no­logy, they are now able to feed the same in­form­a­tion in­to a com­puter to build the tis­sue.

Print­ing came about as a way to scale up the tis­sues and or­gans we were already cre­at­ing by hand,” says An­thony Atala, dir­ect­or of the Wake Forest In­sti­tute of Re­gen­er­at­ive Medi­cine in North Car­o­lina and the lead in­vest­ig­at­or on the pro­ject. Bioprint­ing en­ables re­search­ers to cre­ate tis­sues with much great­er pre­ci­sion and ac­cur­acy.

Atala ex­plains the four tis­sues types in or­der of com­plex­ity: Simplest are flat struc­tures like skin; second are tu­bu­lar struc­tures, such as blood ves­sels or wind­pipes; third are hol­low non-tu­bu­lar or­gans, such as the stom­ach, blad­der, and uter­us; and last and most com­plex by far are sol­id or­gans, such as the heart, kid­ney, and liv­er. These have more cells per area, more cell types, and high­er nu­tri­tion re­quire­ments, and they need much more vas­cu­lar­ity and blood sup­ply.

To this point, sci­ent­ists have only im­planted the first three types from hand­made tis­sues in pa­tients. No bioprin­ted struc­ture has been im­planted.

The mini-or­gans are small enough that they don’t re­quire a com­plex vas­cu­lar tree to sur­vive. The mini-liv­ers, hearts, lungs, and kid­neys are not fully func­tion­al nat­ive or­gans, but they mim­ic the func­tion­al­ity for the test­ing ap­plic­a­tion.

The Wake Forest lab has de­veloped one ma­chine to bioprint dif­fer­ent types of tis­sues. “It’s like with an inkjet print­er, where you have dif­fer­ent col­ors,” says Sang Jin Lee, a coin­vestig­at­or on the pro­ject. “Here we have dif­fer­ent nozzles and dif­fer­ent ma­ter­i­als and cells.”

The re­search­ers are bor­row­ing from com­puter mi­cro­chip and bi­o­sensing tech­no­logy. They will fo­cus on one or­gan type at a time, be­gin­ning with the liv­er. As each is de­veloped, it will be used to test drug re­sponses in­di­vidu­ally; once they are com­pleted, they will be con­nec­ted on the chip to test the full sys­tem re­sponse.

A small hand­ful of oth­er groups are de­vel­op­ing tech­no­lo­gies to print tis­sues, al­though gen­er­ally with a fo­cus on in­di­vidu­al or­gans, rather than the full sys­tem.

Or­gan­ovo, a start-up in San Diego, is us­ing bioprint­ing of tis­sues to im­prove re­search on drugs, with a re­cent fo­cus on the liv­er.

“Re­li­ance on an­im­al mod­els and cells in a petri dish [for test­ing] is prob­lem­at­ic, be­cause many dis­eases can’t get good an­im­al mod­els or don’t be­have sim­il­arly in petri dishes,” says Or­gan­ovo CEO Keith Murphy. The com­pany has suc­ceeded in bioprint­ing liv­er tis­sue that las­ted 40 days in a dish. Murphy says nor­mally the tis­sue stops func­tion­ing in two days, which is not help­ful for test­ing a drug that is ad­min­istered for two years.

Or­gan­ovo is fo­cused on the im­me­di­ate com­mer­cial im­pact of bioprint­ing, with test­ing done on each tis­sue in­de­pend­ently. “We’ve con­tem­plated put­ting [the parts] to­geth­er over time, but you don’t need 10 things to study the liv­er — you need the liv­er,” ex­plains Murphy.

“You can make liv­ing struc­tures act like liv­ing tis­sues,” he says. “You don’t need the full or­gan to have an im­pact.”

The Ad­vanced Man­u­fac­tur­ing Tech­no­logy Group at the Uni­versity of Iowa is bioprint­ing tis­sue with this idea in mind. Ibrahim Ozbolat, AMTech co­dir­ect­or and as­sist­ant pro­fess­or of mech­an­ic­al and in­dus­tri­al en­gin­eer­ing, is fo­cused on cre­at­ing tis­sue that would ac­com­pany — not ne­ces­sar­ily re­place — the pan­creas and pro­duce in­sulin to help pa­tients with dia­betes.

“We’re not in­ter­ested in mak­ing a full nat­ur­al pan­creas,” he says. “We’re work­ing on mak­ing something that is large enough and pro­duces enough in­sulin that is trans­plant­able.”

These pro­jects are all steps along the path to­ward bioprint­ing large or­gans, al­though that goal and its clin­ic­al ap­plic­a­tion is years in the fu­ture.

“[Bioprint­ing or­gans] is still sev­er­al bil­lion dol­lars away,” Murphy says. “If the fund­ing is provided in five years, it could hap­pen quickly. If it takes 20 years, it will be more over that time frame.”

The hope is that as the tech­no­lo­gies con­tin­ue to de­vel­op, the man­u­fac­tur­ing of or­gans could help solve the prob­lem of rap­idly grow­ing trans­plant wait-lists.

Atala notes that over two sets of 10 years, the num­ber of pa­tients on wait-lists has doubled, while the num­ber of or­gans trans­planted has in­creased by only 1 per­cent — a prob­lem the Amer­ic­an Hos­pit­al As­so­ci­ation has de­clared a pub­lic health crisis.

“This is really what drives us to do this,” he says. “Everything builds on the next step.”

What We're Following See More »
TO VISIT US TROOPS
John McCain Paid Secret Visit To Syria
10 hours ago
THE DETAILS

Senator John McCain paid a secret visit to Northern Syria over the weekend during his trip abroad. McCain reportedly went "to speak with American officials and Kurdish fighters leading the charge to push ISIS militants out of Raqqa, the jihadist group’s stronghold." The trip was organized with the help of U.S. military.

Source:
‘MORE WITH LESS’
Trump Budget to Call for Major Cuts
10 hours ago
THE DETAILS

"The Trump administration will deliver its first budget to Congress in mid-March, and the president confirmed Wednesday it will contain major cuts for federal agencies." The blueprint, expected to be released in mid-March, will not include the kinds of specifics usually seen in White House budgets, but rather will instruct the heads of agencies to "do more with less."

Source:
THANKS TO MILITARY ROLE
McMaster Requires Congressional Approval
14 hours ago
THE DETAILS

Congress will need to vote on Donald Trump's pick of Lt. General H.R. McMaster to be his next national security adviser, but not for the reason you think. The position of NSA doesn't require Senate approval, but since McMaster currently holds a three-star military position, Congress will need to vote to allow him to keep his position instead of forcing him to drop one star and become a Major General, which could potentially affect his pension.

Source:
SENT LETTERS TO A DOZEN ORGANIZATIONS
Senate Intel Looks to Preserve Records of Russian Interference
18 hours ago
THE LATEST

"The Senate Intelligence Committee is seeking to ensure that records related to Russia’s alleged intervention in the 2016 U.S. elections are preserved as it begins investigating that country’s ties to the Trump team. The panel sent more than a dozen letters to 'organizations, agencies and officials' on Friday, asking them to preserve materials related to the congressional investigation, according to a Senate aide, who was not authorized to comment publicly. The Senate Intelligence Committee is spearheading the most comprehensive probe on Capitol Hill of Russia’s alleged activities in the elections."

Source:
WON’T INTERFERE IN STRUCTURING NSC OFFICE
White House to Give McMaster Carte Blanche
1 days ago
THE LATEST
×
×

Welcome to National Journal!

You are currently accessing National Journal from IP access. Please login to access this feature. If you have any questions, please contact your Dedicated Advisor.

Login