7 Body Parts Scientists Can Grow in a Petri Dish

You can’t just go out and grow yourself a new heart just yet, but neither is the technology completely out of reach. Scientists have become adept at harnessing human and animal cells to grow artificial versions of complex tissues, including entire limbs. Many of the organs and other body parts researchers are bioengineering aren’t yet ready for the big-time of the human body, but we’re closer than ever to growing replacement tissue for amputees, organ transplant candidates, and more. Here are just a few body parts that can be grown in the lab.

1. Rat limb

Recently, researchers at Massachusetts General Hospital grew an entire rat arm in a dish (above). The forelimb was created with a technique called “decellularization,” which uses living donor cells to regrow organ tissue. The bioengineered rat forelimb contained bone, cartilage, blood vessels, tendons, ligaments, and nerves, and could pave the way for entire limb transplants for amputees. The research is published in the August issue of Biomaterials. 

2. Miniature brain

In 2013, scientists from the Institute of Molecular Biotechnology in Vienna, Austria announced they had successfully created a miniature brain in the lab. Using stem cells, they grew a model of a developing brain that was about the size of an embryonic human brain at nine weeks old. The cerebral organoid didn’t look exactly like a real brain, but it had active neurons and had much the same organizational structure. 

3. Breast tissue

Breast epithelial cells in a gel that encourages mammary gland growth. Image Credit: Image by Haruko Miura; Copyright HMGU

Researchers from the Helmholtz Center for Health and Environmental Research in Germany recently grew miniature mammary glands in an effort to study the development of breast cancer. Healthy tissue taken from women undergoing breast reduction surgery was turned into a gel that allowed the cells to divide and spread much like the mammary gland would during puberty. 

4. Beating heart

Scientists from the University of Pittsburgh used human skin cells to create primitive heart cells. These cells developed into heart muscle, and once exposed to a blood supply, the miniature heart (grown on a mouse heart that had had all its cells removed) began to contract spontaneously. One day, similar tissue could be used to replace heart tissue damaged by a heart attack. Heart tissue regeneration has already proven successful in monkey transplants. 

5. Ear

Image Credit: iStock

For people missing an ear, the reconstruction process is slow and painful, involving harvesting cartilage from the patient’s ribs. However, new techniques might make it easier. Physicians at Cornell University managed to 3D print a realistic ear using living cells from cows and collagen from rat tails. Others have grown ears from cow and sheep cells in the lab using a flexible wire frame.

The ear was then transplanted onto a rat to make sure it retained its shape and flexibility, as seen in the video above.

6. Kidney

Before they were growing legs, researchers at Massachusetts General Hospital created new kidneys. Using the same decellularization process, they grew rat kidneys in a lab. Once transplanted into a rat, the kidneys were able to produce urine just like a normal organ. Scientists have also produced mini-kidneys in the lab, though those have not been transplantable yet. 

7. Tear Gland

A project spearheaded by the Tokyo University of Science bioengineered the glands that produce tears and saliva in research that could help people with chronically dry eyes and mouths. The lab-grown glands were implanted in mice in 2013. The new salivary and lacrimal glands connected to nerves and ducts and were able to successfully secrete tears and saliva. 

Engineers Have Figured Out How the Leaning Tower of Pisa Withstands Earthquakes

Builders had barely finished the second floor of the Tower of Pisa when the structure started to tilt. Despite foundational issues, the project was completed, and eight centuries and at least four major earthquakes later, the precarious landmark remains standing. Now, a team of engineers from the University of Bristol and other institutions claims to have finally solved the mystery behind its endurance.

Pisa is located between the Arno and Serchio rivers, and the city's iconic tower was built on soft ground consisting largely of clay, shells, and fine sand. The unstable foundation meant the tower had been sinking little by little until 2008, when construction workers removed 70 metric tons of soil to stabilize the site. Today it leans at a 4-degree angle—about 13 feet past perfectly vertical.

Now researchers say that the dirt responsible for the tower's lean also played a vital role in its survival. Their study, which will be presented at this year's European Conference on Earthquake Engineering in Greece, shows that the combination of the tall, stiff tower with the soft soil produced an effect known as dynamic soil-structure interaction, or DSSI. During an earthquake, the tower doesn't move and shake with the earth the same way it would with a firmer, more stable foundation. According to the engineers, the Leaning Tower of Pisa is the world's best example of the effects of DSSI.

"Ironically, the very same soil that caused the leaning instability and brought the tower to the verge of collapse can be credited for helping it survive these seismic events," study co-author George Mylonakis said in a statement.

The tower's earthquake-proof foundation was an accident, but engineers are interested in intentionally incorporating the principles of DSSI into their structures—as long as they can keep them upright at the same time.

U2’s 360-Degree Tour Stage Will Become a Utah Aquarium Attraction

The immense stage that accompanied U2 on the band’s 360° Tour from 2009 to 2011 is getting an unexpected second life as a Utah educational attraction. It will soon be installed over a new plaza at the Loveland Living Planet Aquarium outside Salt Lake City.

The Claw, a 165-foot-tall structure shaped like a large spaceship balanced on four legs—a design inspired by the space-age Theme Building at Los Angeles International Airport—was built to house a massive speaker system and cylindrical video screen for the band’s performances. Underneath it, a 360° stage allowed U2 to play to audiences surrounding the structure in all directions. To make it easier to tour 30 different countries with the elaborate system, which took more than a week to put together at each concert location, the band had several versions built.

U2 and its management have been looking for a buyer for the 190-ton structures since the tour ended in 2011, and it seems they have finally found a home for one of them. One of the two remaining Claw structures is coming to the Utah aquarium, where it’s being installed as part of a plaza at the institution’s new, 9-acre Science Learning Campus.

A four-legged, industrial-looking video-and-sound-projection rig rises over a crowd at a concert
The Claw at a Dublin concert in 2009
Kristian Strøbech, Flickr // CC BY 2.0

As the only Claw in the U.S., the alien-looking feat of engineering will be "preserved and sustainably repurposed as a Utah landmark and symbol of science exploration and learning," according to the aquarium's press release. As part of the expansion project, the 2300-square-foot stage system will play host to festivals, movies, and other special events in two venues, one with 7000 seats and the other with 350.

The $25 million Science Learning Campus hasn’t been built yet—construction is starting this fall—so you’ll have to wait awhile to relive your U2 concert experience at the aquarium.


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