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 »
SEX WOULD BE CONSIDERED BINARY
HHS Could Nix Title IX Protections for Transgender Students
15 minutes ago
THE DETAILS

"The Department of Health and Human Services is spearheading an effort to establish a legal definition of sex under Title IX, the federal civil rights law that bans gender discrimination in education programs that receive government financial assistance, according to a memo obtained by The New York Times. The department argued in its memo that key government agencies needed to adopt an explicit and uniform definition of gender as determined 'on a biological basis that is clear, grounded in science, objective and administrable.' The agency’s proposed definition would define sex as either male or female, unchangeable, and determined by the genitals that a person is born with."

Source:
SAYS HIS DEATH STEMMED FROM A FISTFIGHT
Saudis Admit Khashoggi Killed in Embassy
2 days ago
THE LATEST

"Saudi Arabia said Saturday that Jamal Khashoggi, the dissident Saudi journalist who disappeared more than two weeks ago, had died after an argument and fistfight with unidentified men inside the Saudi Consulate in Istanbul. Eighteen men have been arrested and are being investigated in the case, Saudi state-run media reported without identifying any of them. State media also reported that Maj. Gen. Ahmed al-Assiri, the deputy director of Saudi intelligence, and other high-ranking intelligence officials had been dismissed."

Source:
ROGER STONE IN THE CROSSHAIRS?
Mueller Looking into Ties Between WikiLeaks, Conservative Groups
2 days ago
THE LATEST

"Special counsel Robert Mueller’s investigation is scrutinizing how a collection of activists and pundits intersected with WikiLeaks, the website that U.S. officials say was the primary conduit for publishing materials stolen by Russia, according to people familiar with the matter. Mr. Mueller’s team has recently questioned witnesses about the activities of longtime Trump confidante Roger Stone, including his contacts with WikiLeaks, and has obtained telephone records, according to the people familiar with the matter."

Source:
PROBING COLLUSION AND OBSTRUCTION
Mueller To Release Key Findings After Midterms
2 days ago
THE LATEST

"Special Counsel Robert Mueller is expected to issue findings on core aspects of his Russia probe soon after the November midterm elections ... Specifically, Mueller is close to rendering judgment on two of the most explosive aspects of his inquiry: whether there were clear incidents of collusion between Russia and Donald Trump’s 2016 campaign, and whether the president took any actions that constitute obstruction of justice." Mueller has faced pressure to wrap up the investigation from Deputy Attorney General Rod Rosenstein, said an official, who would receive the results of the investigation and have "some discretion in deciding what is relayed to Congress and what is publicly released," if he remains at his post.

Source:
PASSED ON SO-CALLED "SAR" REPORTS
FinCen Official Charged with Leaking Info on Manafort, Gates
2 days ago
THE DETAILS
"A senior official working for the Treasury Department's Financial Crimes Enforcement Network (FinCEN) has been charged with leaking confidential financial reports on former Trump campaign advisers Paul Manafort, Richard Gates and others to a media outlet. Prosecutors say that Natalie Mayflower Sours Edwards, a senior adviser to FinCEN, photographed what are called suspicious activity reports, or SARs, and other sensitive government files and sent them to an unnamed reporter, in violation of U.S. law."
Source:
×
×

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