Select Page
How to Make a Pig Heart Transplant Last in a Person

How to Make a Pig Heart Transplant Last in a Person

With any organ transplant, doctors are trying to balance how to prevent infections while tamping down the immune system. Without immunosuppressive drugs, the transplant organ will be rejected. But giving patients too much of these drugs makes them susceptible to infections.

That’s what researchers think happened in Bennett’s case. To treat the CMV infection, doctors gave Bennett a therapy called intravenous immunoglobulin, which is meant for patients with compromised immune systems, including transplant patients. A concentrated pool of antibodies from thousands of human donors, the treatment likely contained natural antibodies that attacked the pig organ and damaged muscle cells.

The Maryland doctors are taking different steps to prevent Faucette’s new heart from being rejected. For one, they told WIRED in December that they had developed a new, more sensitive test to detect very small amounts of pig virus DNA. Before the latest transplant, they tested the donor pig regularly for CMV and other porcine viruses, as well as bacteria and parasites. “At the present time, we have no reason to believe this donor pig is infected with porcine PCMV, which is the virus that was identified in our first xenotransplant recipient,” a university spokesperson told WIRED in an email.

Doctors are treating Faucette with traditional immunosuppressive drugs, along with an investigational antibody therapy called tegoprubart, developed by California biotech company Eledon Pharmaceuticals. The drug works by blocking CD154, a protein involved in immune rejection, and is given via IV every three weeks. Like other immunosuppressive drugs, Faucette must receive it for the rest of his life to prevent his new heart from being rejected. “When you block this receptor, it’s very, very effective to prevent transplant rejection,” says Steve Perrin, Eledon’s president and chief scientific officer.

When the Maryland surgeons performed Bennett’s transplant in January 2022, they didn’t have access to Eledon’s drug because it had not yet been tested in humans. Now, more than 100 people have received the drug in early clinical trials. Tegoprubart has also been tested in non-human primates and has been shown to increase the life of transplanted pig organs in those animals.

The next few weeks will be crucial to determine whether the transplanted pig heart will continue to function normally. “I’m hopeful that this will be the correct regimen for the patient and that he will be able to live a long life with the xenograft,” says Jayme Locke, an abdominal transplant surgeon at the University of Alabama at Birmingham who wasn’t involved in the heart cases. In August, Locke’s team published a study showing that a genetically modified pig kidney functioned normally in a brain-dead patient for a week.

In a separate xenotransplant experiment, a team at NYU Langone announced earlier this month that it kept a pig kidney working for two months in a brain-dead person.

The US Food and Drug Administration granted emergency approval for Faucette’s surgery earlier this month through its “compassionate use” pathway. This process, which was also used for Bennett’s transplant, is applied when an unapproved medical product—in this case, the genetically modified pig heart—is the only option for a patient with a serious or life-threatening condition.

Pierson thinks these individual cases of pig-to-human transplants will help generate evidence needed for more formal clinical trials that will include multiple patients. He is optimistic that a pig heart will function longer in this second patient. “Full stop,” he says. “It may not work every time we do it, but we’re going to learn a lot from these one-offs.”

Explore the Ancient Aztec Capital in This Lifelike 3D Rendering

Explore the Ancient Aztec Capital in This Lifelike 3D Rendering

The Aztecs did not count time on an infinite scale, as we do, but in cyclical 52-year periods, and at the completion of each cycle, life and the world would begin anew. To initiate the start of a new cycle the New Fire ceremony was held, the most important Aztec ritual. Every 52 years the inhabitants of Tenochtitlán discarded the images of their gods and all their domestic utensils and extinguished any fires in their homes and temples. As the city sat in complete darkness, priests would leave the Templo Mayor and travel to Huixachtlan (Cerro de la Estrella, or Hill of the Star), and at the summit they would perform a ceremony to light a new fire. The ritual was surrounded with uncertainty and fear because it was believed that if the new fire was not successfully lit, the world would end and the stars would turn into monsters that would devour humanity. During the five days prior to the ceremony, the people let their fires go out and destroyed their household goods, and then they waited, fasting and lamenting, pondering the possibility of the collapse of the world. That moment was beautifully re-created in 3D by Kole.

El Cerro de la Estrella or the Hill of the Star.

El Cerro de la Estrella, or the Hill of the Star.

“The really hard part was gathering all the information and then trying things out,” explains Thomas Kole. “How do you create a city when you don’t really know anything about it? How do you start gathering that information? That was really difficult and involved throwing out a lot of things when I found different sources with conflicting information. That’s part of being a pioneer, venturing into the unknown, into what no one has done before, but that’s also very difficult because it takes a lot of time. Also, I don’t speak Spanish and I’m not an academic, so I really approached this as an outsider,” Kole says.

“The year is 1518. Mexico-Tenochtitlán, once an unassuming settlement in the middle of Lake Texcoco, is now a bustling metropolis. It is the capital of an empire ruling over, and receiving tribute from, more than five million people. Tenochtitlán is home to 200,000 farmers, artisans, merchants, soldiers, priests, and aristocrats. At this time, it is one of the largest cities in the world. Today, we call this city Ciudad de Mexico—Mexico City,” reads the site, which opens with a stylized Tenochtitlán glyph, made by Mi Corazón Mexica.

A New Proof Moves the Needle on a Sticky Geometry Problem

A New Proof Moves the Needle on a Sticky Geometry Problem

The original version of this story appeared in Quanta Magazine.

In 1917, the Japanese mathematician Sōichi Kakeya posed what at first seemed like nothing more than a fun exercise in geometry. Lay an infinitely thin, inch-long needle on a flat surface, then rotate it so that it points in every direction in turn. What’s the smallest area the needle can sweep out?

If you simply spin it around its center, you’ll get a circle. But it’s possible to move the needle in inventive ways, so that you carve out a much smaller amount of space. Mathematicians have since posed a related version of this question, called the Kakeya conjecture. In their attempts to solve it, they have uncovered surprising connections to harmonic analysis, number theory, and even physics.

“Somehow, this geometry of lines pointing in many different directions is ubiquitous in a large portion of mathematics,” said Jonathan Hickman of the University of Edinburgh.

But it’s also something that mathematicians still don’t fully understand. In the past few years, they’ve proved variations of the Kakeya conjecture in easier settings, but the question remains unsolved in normal, three-dimensional space. For some time, it seemed as if all progress had stalled on that version of the conjecture, even though it has numerous mathematical consequences.

Now, two mathematicians have moved the needle, so to speak. Their new proof strikes down a major obstacle that has stood for decades—rekindling hope that a solution might finally be in sight.

What’s the Small Deal?

Kakeya was interested in sets in the plane that contain a line segment of length 1 in every direction. There are many examples of such sets, the simplest being a disk with a diameter of 1. Kakeya wanted to know what the smallest such set would look like.

He proposed a triangle with slightly caved-in sides, called a deltoid, which has half the area of the disk. It turned out, however, that it’s possible to do much, much better.

The deltoid to the right is half the size of the circle, though both needles rotate through every direction.Video: Merrill Sherman/Quanta Magazine

In 1919, just a couple of years after Kakeya posed his problem, the Russian mathematician Abram Besicovitch showed that if you arrange your needles in a very particular way, you can construct a thorny-looking set that has an arbitrarily small area. (Due to World War I and the Russian Revolution, his result wouldn’t reach the rest of the mathematical world for a number of years.)

To see how this might work, take a triangle and split it along its base into thinner triangular pieces. Then slide those pieces around so that they overlap as much as possible but protrude in slightly different directions. By repeating the process over and over again—subdividing your triangle into thinner and thinner fragments and carefully rearranging them in space—you can make your set as small as you want. In the infinite limit, you can obtain a set that mathematically has no area but can still, paradoxically, accommodate a needle pointing in any direction.

“That’s kind of surprising and counterintuitive,” said Ruixiang Zhang of the University of California, Berkeley. “It’s a set that’s very pathological.”

Climate Change Has Finally Come For Burning Man

Climate Change Has Finally Come For Burning Man

Because Burning Man chooses to situate its event in the Nevada desert, resources, including food and generators, need to be trucked to the site—a challenge given heavy rain has made roads impassable. It’s this, in part, that explains why Chris Rock decided to abandon the event: In an Instagram Story, he posted that he understood portable toilets couldn’t be emptied, supplies delivered, and extra generators sent because of flooding.

But others haven’t given up. For Anya Kamenetz, who attended her first Burning Man in 2003, the rainfall hasn’t fazed her—or her fellow campmates. “We’re really prepared,” she says, though she admits that the weather’s impact means “you can’t get around the city at all.” Vehicles are banned from traveling around for fear of making the ground worse or getting stuck and blocking routes earmarked as exit routes for when it’s safe to leave. Those who choose to walk around the site can still party as always, but some have decided against doing so. Kamenetz and her campmates are continuing as normal, with some significant alterations. “We don’t know when we’re going to get drinking water—or if—or portapotty services, or fuel, or gray water services,” she says. As a result, they’re conserving as much water as possible. They’re not urinating in the portapotties, but on the ground. “We’re not rationing food, but we’re just trying to make [sure] everyone is as thoughtful as possible,” she says. Showers are out—as is dishwashing.

The rainfall began on the afternoon of September 1 around 1.30 pm, and didn’t stop for around nine hours, Kamenetz says. “At first you’re like, ‘Well, it’ll clear up and we’ll go out more later.’ But then we were making dinner and [it] was like: ‘Wow, this is going to be impossible.’” By nightfall on September 2, with the ground turning from desert to quagmire, Kamenetz had resigned herself to being stuck on site. For how long that will be, she’s less sure. “Every time it rains more it sets the clock back a little bit,” she says. However, when there are breaks in the rain, the timescale gets expedited. On September 2, people were uncertain they’d get to leave before September 7; now they’re hopeful to be free sooner.

Kamenetz has been surprised by how well the 70,000-strong community has taken the weather’s impact on their party. “Burning Man people really pride themselves on first of all being prepared to confront the elements, and secondly, being co-operative and being in a good spirit,” she says. She has seen a few confrontations between those who are demanding to leave, getting into their cars and making a break for it, and other “Burners” (as attendees are called), who are stopping them, but mostly Kamenetz has seen people accepting their fate.

An annual getaway for hedonists and a particular subsection of the ultra-rich Silicon Valley tech community has always been a bit of an odd sell: Pitch up a vast, temporary city of 70,000 people every year, with attendees jetting in from all four corners of the globe to party. Some attendees of the event have repeatedly highlighted concerns about the impact the festival has on the planet. The event reports its carbon footprint to be 100,000 tons of carbon dioxide, more than 90 percent of which is accounted for by travel to and from the site. By comparison, Glastonbury’s carbon footprint is net negative, according to one analysis. Burning Man looks likely to miss its 2030 target of being carbon negative.

The High-Stakes Calculus of Preventing Wildfires by Burying Power Lines

The High-Stakes Calculus of Preventing Wildfires by Burying Power Lines

Not long after the deadliest wildfire in modern American history swept through Lahaina, Maui, on August 8, speculation began swirling about a notorious igniter of out-of-control blazes: electrical equipment. 

Although investigators have yet to officially determine the cause of the wildfire, witnesses reported power poles snapping in the 60-mile-an-hour winds that were pouring down the nearby mountains, showering dried vegetation in sparks. And last week, the County of Maui hit Hawaiian Electric with a lawsuit, accusing the utility of neglecting its duty to power down its infrastructure, given the known risk of such high winds sparking wildfires. 

On Sunday, the utility responded with a press release, saying that at 6:30 am, a morning fire “appears to have been caused by power lines that fell in high winds.” Firefighters extinguished that blaze, the press release continues, but another fire popped up in the same area at about 3 pm, when the utility says its lines had been de-energized for more than six hours. That fire then spread into Lahaina. 

“Hawaiian Electric has now admitted to starting the Lahaina Fire on August 8th,” said John Fiske, the counsel representing the County of Maui, in a statement provided to WIRED. “In its recent release, issued Sunday night before the markets opened, Hawaiian Electric appears to have suggested there could be a possible second ignition source in the afternoon of August 8th without providing any supporting information.”

Investigators have yet to determine if there were two separate ignitions, or if the afternoon fire was a flare-up of the one earlier in the morning. Hawaiian Electric declined to answer questions for this story, referring WIRED to its press release.

If investigators ultimately conclude that the fire’s cause was electrical equipment, the Maui fire will join other recent city-razing blazes in the American West that were started—and then powered—by fierce winds rattling the power infrastructure. But even if utilities are able to prevent their equipment from sparking blazes—like by “undergrounding” lines, meaning enclosing them in piping and burying them in trenches—there are lots of other ways to start an epic conflagration on a warming planet.

Wind is essential to whipping up the biggest, fastest, deadliest wildfires. And electricity can be a dangerous add-on: If gusts down trees into power lines, or utility poles snap or fall over, all that jostling can send sparks into the vegetation below. Winds fan the growing flames, driving the blaze across the landscape with such speed that people in the way don’t have time to evacuate. (Strong winds also loft embers into the air, and can carry them perhaps 2 miles ahead of the main fire, creating new fires and making it harder for firefighters to manage.) Towns like Lahaina in the “wildland-urban interface,” where unkempt vegetation butts up against structures or intermingles with them, are especially vulnerable to such fast-moving fires. 

America’s aging grid wasn’t designed for today’s climate, with its warmer atmosphere, intense, longer-lasting droughts, and increasingly dry landscapes. So electrical-sparked, wind-driven fires are growing more destructive and deadly. In 2017 the Tubbs Fire destroyed over 5,600 structures and killed 22, and in 2018 the Camp Fire destroyed the town of Paradise and killed 85. In 2019, the California utility Pacific Gas and Electric, or PG&E, reached a $13.5 billion settlement for wildfires linked to its equipment, including both of these fires. Both have now been eclipsed by the Lahaina fire in terms of the human cost: At least 115 people have been confirmed dead, with hundreds still missing.