Day: 02/14/2024

An asteroid hit ended dinosaurs’ reign. But did birds flourish because of it?

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STORY HIGHLIGHTS

Modern birds have evolved from some of the smaller dinosaurs and it is held to be logical that in the food-deficient aftermath of the asteroid hit, smaller life-forms were able to survive as opposed to their much larger ‘dino’ counterparts. But a study now contends that asteroid-hit did not have an effect on the evolution of birds as they had started diversifying even before the catastrophic event

An asteroid hit Earth 65 million years ago and in one stroke, started a process that resulted in the elimination of 75 per cent of life on Earth over the next decade and ended the reign of dinosaurs. It is almost unanimously held that the catastrophic event paved the way for mammals and other forms of life to thrive and for humans to ultimately develop. But did the asteroid help birds?

Modern birds have evolved from some of the smaller dinosaurs and it is held to be logical that in the food-deficient aftermath of the asteroid hit, smaller life-forms were able to survive as opposed to their much larger ‘dino’ counterparts. This eventually resulted in the evolution of the ‘normal-sized’ birds we see today.

But a study now contends that the asteroid hit did not have an effect on the evolution of birds as they had started diversifying even before the catastrophic event.

To arrive at their conclusion, the scientists studied 124 bird species.

“We found that this catastrophe didn’t have an impact on modern birds,” said Dr Shaoyuan Wu, an evolutionary biologist at Jiangsu Normal University, China

As reported by The New York Times, the international team of researchers found during the study that birds that are alive today had a common ancestor 130 million years ago. The ancestor evolved into different birds over millennia. However, the researchers say that the ‘family tree’ of this evolution was splitting steadily, both before and after the asteroid hit.

In other words, the asteroid hit in itself did not have an influence on the evolution of birds, contend the researchers.

The scientific community in general continues to study the asteroid impact that came close to eliminating life on Earth by causing huge tsunamis, massive forest fires and triggering a decade-long winter.

The Earth’s Core Is Cooling Way Faster Than We Thought, Scientists Say

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Cooling Earth.

OUR PLANET IS TURNING INTO A ROCKY PLANET LIKE MERCURY OR MARS MUCH “FASTER THAN EXPECTED.”

According to new research, the core of the Earth is cooling much faster and sooner than originally anticipated — a new mystery that could throw a wrench in our understanding of the planet’s evolution.

To get a better sense of how far along the Earth is in the process, scientists are studying the thermal conductivity of the minerals present in the layer between the planet’s core and mantle. The faster that hot center passes heat to the planet’s outer layers, the faster the Earth is losing the heat present in its core.

Heating Rocks

In a lab simulation, a team of researchers from ETH Zurich in Switzerland and the Carnegie Institution for Science applied immense amounts of pressure and heat to a mineral called bridgmanite — which is found in the transitional zone between the core and mantle — to simulate the conditions deep below the surface. They then measured its thermal conductivity to get a better sense of the cooling processes at play.

The results were surprising.

“This measurement system let us show that the thermal conductivity of bridgmanite is about 1.5 times higher than assumed,” said ETH professor Motohiko Murakami, lead author of a paper about the findings published in the journal Earth and Planetary Science Letters, in a statement.

In other words, the heat from the core is being passed on at a much faster rate than previously thought, leading to the greater cooling of the Earth.

A New Perspective

The study could rewrite what we already know about the dynamic processes leading to the slowing down of convection currents.

“Our results could give us a new perspective on the evolution of the Earth’s dynamics,” Murakami explained. “They suggest that Earth, like the other rocky planets Mercury and Mars, is cooling and becoming inactive much faster than expected.”

The researcher did, however, note we didn’t know enough to pinpoint how long it will take for convection currents to stop altogether.

Why don’t we feel Earth spinning?

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Earth moves around the sun at 67,000 mph and makes a full rotation once every 24 hours. So why can’t we feel the Earth’s rotation?

Earth makes one rotation every 24 hours and orbits the sun at around 67,000 mph (110,000 km/h). So why can’t we feel that? 

When you’re going around and around on a carnival ride, you feel it — you’re pulled outward, and all you can do is hang on. Our planet is rotating much faster than that, so why aren’t we all holding on for dear life? Why can’t we feel Earth’s rotation?

There are two major reasons. One is that Earth’s rotation is smooth.

“If you’re in a car and you’re going at a constant speed on the highway, if you close your eyes and tune out the road noise, you would feel stationary,” said Stephanie Deppe, an astronomer and content strategist for the Vera C. Rubin Observatory in Chile.

If that car were hitting the brakes repeatedly, you’d know you were in motion. But because it stays at a constant speed, you feel motionless

Put another way, “we know there’s no such thing as absolute motion. The only thing that matters is relative motion,” said Greg Gbur, a professor of physics and optical science at the University of North Carolina at Charlotte.

“People like Newton and Galileo pointed this out,” he said. “Galileo famously imagined a thought experiment of being in the bowels of a ship. If the ship is sailing on calm water versus the ship being docked at port, you’re not going to notice any difference according to the laws of physics.”

And like being in a car or on a ship, everything on Earth is also moving with us. If you roll down a car window on the highway, you get a face full of wind as the car slams you into millions of air molecules. But inside the car with the window up, the air moves with you and you don’t feel the wind.

Likewise, our planet’s atmosphere is moving just as fast as we are — so, relative to us, it’s stationary.

The other reason we don’t feel Earth’s rotation is gravity. “The force of gravity holding us to the Earth is much, much, much stronger than the force that would send us flying outward,” Deppe said.

The feeling of being pulled outward from a carnival ride, or a car doing doughnuts, is called centripetal acceleration. “It’s the feeling of inertia,” Gbur said. “Your body wants to keep going in a straight line, but if you’re in your car, the car is trying to pull you in a circle.”

Earth’s spin pulls everything outward in the same way, but the force keeping everything stuck to the ground overpowers that pull.

“The acceleration of gravity is about 9.8 m/s^2 on the Earth’s surface, and the reduction of that due to the rotation of the Earth at the equator, where things are moving the fastest, is about 0.03 m/s^2, which is measurable but really tiny compared to what we feel from gravity itself, so we don’t notice it,” Gbur said.

Most detailed X-ray sky map bolsters standard model of cosmology

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This new map of the Universe suggests dark matter shaped the cosmos

The eROSITA telescope’s detailed pictures are among the most precise cosmological measurements ever made.

Half of the X-ray sky, projected onto a circle with the centre of the Milky Way on the left and the galactic plane running horizontally.
In this map of a celestial hemisphere — compiled from data from the eROSITA telescope —
the colours reflect the wavelengths of X-rays. Hot gas haloes surrounding galaxy clusters have broad-band emissions (white), as do black holes (white dots); diffuse emissions have long wavelengths (red); and in the central regions of the Milky Way, dust blocks longer-wavelength emissions, so that only short-wavelength X-rays are visible (blue or black). Multicoloured clouds are supernova remnants. Credit: MPE, J. Sanders for the eROSITA consortium.

Astronomers have reconstructed nearly nine billion years of cosmic evolution by tracing the X-ray glow of distant clusters of galaxies. The analysis supports the standard model of cosmology, according to which the gravitational pull of dark matter — a still-mysterious substance — is the main factor shaping the Universe’s structure.

“We do not see any departures from the standard model of cosmology,” says Esra Bulbul, a senior member of the team and an astrophysicist at the Max Planck Institute for Extraterrestrial Physics (MPE) in Garching, Germany. The results are described1 in a preprint posted online on 14 February.

The galactic clusters were spotted in the most detailed picture ever taken of the sky using X-rays, which was published late last month. This image revealed around 900,000 X-ray sources, from black holes to the relics of supernova explosions.Space telescope to chart first map of the Universe in high-energy X-rays

The picture was the result of the first six months of operation of eROSITA (Extended Roentgen Survey with an Imaging Telescope Array), one of two X-ray telescopes that were launched into space in July 2019 aboard the Russian spacecraft SRG (Spectrum-Roentgen-Gamma). eROSITA scans the sky as the spacecraft spins, and collects data over wider angles than are possible for most other X-ray observatories. This enables it to slowly sweep the entire sky every six months.

By an unusual arrangement, the eROSITA team is split into two — with a group based in Germany and one based in Russia — and each has exclusive access to eROSITA data from only half of the sky. The mission was originally intended to cover the sky eight times. But Russia’s full-scale invasion of Ukraine in 2022 led the German government to freeze its collaborations, and eROSITA was put on stand-by. By then, it had completed four full sky scans.

The data that Bulbul and her collaborators have used so far were from their half of the sky, collected during the first scan. Even so, the results are already among the most precise cosmological measurements ever made. It is unclear when the Russia-based group will publish its data and analysis.

Evolving Universe

By looking across vast distances, telescopes such as eROSITA also peer back in time, to see the various stages of cosmic evolution. As the Universe expands, the space between galaxies tends to grow larger, but at the same time, galaxies are pulled towards one another by gravity, including their own and especially that of dark matter. As a result, giant cosmic voids form and expand, and matter increasingly clumps into a web of giant clusters of galaxies.

Astrophysicist Vittorio Ghirardini at the MPE worked with Bulbul and other collaborators to map the haloes of intergalactic gas surrounding more than 5,000 galaxy clusters in 3D using a combination of eROSITA’s data and an existing map made by the Dark Energy Survey (DES), which uses a telescope in Chile. “Since X-rays are very powerful at detecting haloes, we can be very certain that there is a very big structure there,” Ghirardini says.

The observations span a vast area and time period — approximately nine billion years. This allowed the researchers to calculate some of the most crucial parameters of cosmic evolution, including ‘lumpiness’ — how much the total mass of matter has concentrated in the cosmic web at any given time. In 2017, similar calculations based on DES data alone seemed to show2 that the web had become lumpy much more slowly than the standard model predicts, but in the latest analysis, that discrepancy has gone away. (Results made public last year from a separate cosmology experiment also indicated harmony with the standard model3.)

Neutrino boundary

Furthermore, the galactic-cluster data enabled the team to tease out the role of neutrinos in shaping the cosmic web. Copious amounts of these elementary particles were produced in the Big Bang, and their low masses and reluctance to interact with other particles mean that they act like dark matter, forming haloes around galaxies. From this information, the astrophysicists calculated that neutrinos could have masses of no more than 0.22 electronvolts (an electron has a mass of around 500,000 eV). “These are the tightest measurements of the neutrino masses available,” Bulbul says; lab measurements on Earth have so far established4 a larger upper limit of 0.8 eV.

Even if eROSITA’s observations never resume, the team’s work is not over yet. “We have a lot more data we are working on,” says Bulbul. The team will eventually be able to map gas halos that are smaller, fainter or more distant than the ones in the current catalogue — and to increase the precision of the measurements.

The same applies to the other types of X-ray source mapped by eROSITA, such as quasars, the intensely bright supermassive black holes at the centres of many galaxies. Studies on this trove of information have only just begun, says eROSITA spokesperson Mara Salvato, an astrophysicist at the MPE. “By the end of the mission, we expect to catalogue three million objects.”

Scientists finally discovered how ants took over nearly the entire planet

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The world is teeming with an estimated 14,000 species of ants that, taken together, number in the quadrillions! These ubiquitous insects have spread across all continents except for the frozen expanse of Antarctica, marking an incredible evolutionary success story. 

But how did they manage to establish such a significant presence on our planet? 

A team of researchers went to the bottem of this and published their findings in the peer-reveiwed scientific journal Evolution Letters. In this article we will discuss their intruiging findings

The team, led by Matthew Nelsen, a research scientist at the Field Museum in Chicago, combined fossil records, DNA data, and modern species’ habitat preferences to retrace the ants’ journey. They painstakingly collected and studied climate data of 1,400 modern ant species and then contrasted this with a time-scaled reconstruction of the ant family tree derived from genetic information and fossilized amber-encased ants.

UNRAVELING THE ANT-PLANT SYMBIOSIS THROUGH EVOLUTION

In their research, the scientists discovered that ants’ evolutionary path was intertwined with that of flowering plants. Approximately 140 million years ago, ants and flowering plants – or angiosperms – originated and gradually spread from forests to other habitats. This simultaneous spread wasn’t a mere coincidence; in fact, the ants were closely following the flowering plants’ lead.

Exploring this further, the team found that around 60 million years ago, ants primarily resided in forested areas, building their nests underground. However, as some forest-dwelling plants evolved to release more water vapour through their leaves, creating rainforest-like conditions, ants began to ascend. 

Alongside ants, other creatures like frogs and snakes also transitioned to this new, wetter environment. They weren’t just adapting to a new climatic condition – they were forming a brand new, vibrant ecosystem up in the trees!

The scientists also discovered that as flowering plants began to adapt to drier, more arid regions outside of the forest, ants took this as a cue to move as well. Plants seem to have incentivized this migration by evolving specific features to feed ants, such as fleshy appendages on seeds called elaiosomes. As ants harvested these elaiosomes, they inadvertently aided in the dispersal of plant seeds, creating a mutual benefit for both species.

THE FAR-REACHING IMPACT OF PLANT COMMUNITIES ON BIODIVERSITY

The research provides more than just fascinating insights into the ants’ evolutionary journey. It underlines the profound and cascading impact that shifts in plant communities – due to historical and modern climate change – can have on other dependent organisms, including ants. As Nelsen points out, this research reinforces the idea that plants play a critical role in shaping ecosystems, and any alterations to their communities can have significant ripple effects on the biodiversity and the structure of ecosystems.

Plants have been the silent architects of the world, influencing the ecology and evolution of numerous organisms, including ants. This study has underscored that, providing another compelling example of the powerful interplay between different life forms on our planet. Our ant allies and their blossoming companions indeed share a deep-seated relationship, having jointly navigated the path of evolution for over a hundred million years. It’s a testament to the intricacy of life and its remarkable adaptability, reminding us of the delicate balance that exists in nature.

World First: 13-Year-Old Child Cured of a Deadly Brain Cancer

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woman looking at a computer screen with brain scans displayed

When Lucas was diagnosed with a rare type of brain tumor at the age of six, there was no doubting the prognosis.

French doctor Jacques Grill gets emotional when he remembers having to tell Lucas’s parents that their son was going to die.

However, seven years later, Lucas is now 13 years old and there is no trace of the tumor left.

The Belgian boy is the first child in the world to have been cured of brainstem glioma, a particularly brutal cancer, according to the researchers who treated him.

“Lucas beat all the odds” to survive, said Grill, head of the brain tumor programme at the Gustave Roussy cancer center in Paris.

The tumor, which has the full name diffuse intrinsic pontine glioma (DIPG), is diagnosed every year in around 300 children in the United States, and up to 100 in France.

Ahead of International Childhood Cancer Day on Thursday, the medical community has praised advances that mean 85 percent of children now survive more than five years after being diagnosed with cancer.

But the outlook for children with the DIPG tumor remains grim – most do not live a year beyond diagnosis. A recent study found that only 10 percent were alive two years on.

Radiotherapy can sometimes slow the rapid march of the aggressive tumor, but no drug has been shown to be effective against it.

No other case like him

Lucas and his family traveled from Belgium to France so that he could become one of the first patients to join the BIOMEDE trial which tests potential new drugs for DIPG.

From the start, Lucas responded strongly to the cancer drug everolimus, which he was randomly assigned.

“Over a series of MRI scans, I watched as the tumor completely disappeared,” Grill told AFP.

But the doctor did not dare stop the treatment regimen – at least until a year and a half ago, when Lucas revealed he was no longer taking the drugs anyways.

“I don’t know of any other case like him in the world,” Grill said.

Exactly why Lucas so fully recovered, and how his case could help other children like him in the future, remains to be seen.

Seven other children in the trial survived years after being diagnosed, but only Lucas’s tumor completely vanished.

The reason these children responded to the drugs, while others did not, was likely due to the “biological particularities” of their individual tumors, Grill said.

“Lucas’s tumor had an extremely rare mutation which we believe made its cells far more sensitive to the drug,” he added.

Reproducing Lucas

The researchers are studying the genetic abnormalities of patients’ tumors as well as creating tumor ” organoids,” which are masses of cells produced in the lab.

“Lucas’s case offers real hope,” said Marie-Anne Debily, a researcher supervising the lab work.

“We will try to reproduce in vitro the differences that we have identified in his cells,” she told AFP.

The team wants to reproduce his genetic differences in the organoids to see if the tumor can then be killed off as effectively as it was in Lucas.

If that works, the “next step will be to find a drug that has the same effect on tumor cells as these cellular changes,” Debily said.

While the researchers are excited about this new lead, they warned that any possible treatment is still a long way off.

“On average, it takes 10-15 years from the first lead to become a drug – it’s a long and drawn-out process,” Grill said.

David Ziegler, a pediatric oncologist at Sydney Children’s Hospital in Australia, said that the landscape for DIPG has dramatically changed over the last decade.

Breakthroughs in the lab, increased funding and trials such as BIOMEDE make “me convinced that we will soon find that we are able to cure some patients,” Ziegler told AFP.

Unlocking the Secrets of Stem Cells in Zero Gravity.

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Embryonic Stem Cell Illustration

The Expedition 70 crew at the International Space Station embarked on a busy week filled with stem cell research and preparations for the arrival of the Progress 87 cargo craft.

A busy week of science and prep for an upcoming cargo delivery kicked off aboard the International Space Station on Monday as the Expedition 70 crew set its sights on new stem cell research and orbital training.

Two cosmonauts, Flight Engineers Oleg Kononenko and Nikolai Chub, are gearing up to be on duty monitoring the automated docking of the Progress 87 cargo craft, which is scheduled to launch from the Baikonur Cosmodrome in Kazakhstan at 10:25 p.m. EST on Wednesday, February 14. Loaded with nearly three tons of food, fuel, and supplies, Progress will dock to the station around 1:12 a.m. Saturday, February 17. In preparation of the upcoming cargo delivery, the cosmonauts trained on the telerobotically operated rendezvous unit, or TORU, which allows them to remotely control an arriving spacecraft in the unlikely event it could not automatically dock.

Meanwhile, the Progress 85 cargo craft, which arrived to the station about six months ago, will undock from the station at 9:09 p.m. Monday, February 12 About three hours later, it will be commanded to deorbit before harmlessly burning up over the Pacific Ocean.

Advancements in Stem Cell Research

While training for the upcoming mission was underway, two NASA Flight Engineers, Jasmin Moghbeli and Loral O’Hara, focused a majority of their day on the Mesenchymal Stem Cells in Microgravity Induced Bone Loss (MABL-A) investigation. MABL-A, which was delivered aboard Northrop Grumman’s 20th Commercial Resupply Mission nearly two weeks ago, assesses the effects of microgravity on bone marrow stem cells. The duo worked separately throughout the day to sample BioCells inside the habitat with assistance from JAXA (Japan Aerospace Exploration Agency) Flight Engineer Satoshi Furukawa.

NASA astronaut and Expedition 70 Flight Engineer Jasmin Moghbeli works inside the Life Science Glovebox for the Microgravity Associated Bone Loss-A investigation. She was processing bone cell samples obtained from human donors on Earth and exploring space-caused bone loss. Results may help doctors learn how to protect and treat astronauts on long-term missions and inform treatments for bone conditions on Earth.

Orbital Training and Equipment Setup

Later on, Moghbeli donned the Bio-Monitor garment and headband, which monitors and records vital signs while crew members perform daily activities. Afterward, she was joined by Furukawa, ESA (European Space Agency) Commander Andreas Mogensen, and Roscosmos Flight Engineer Konstantin Borisov to complete orbital training in the unlikely event an emergency were to occur on station.

Near the end of the day, Mogensen, with assistance from Furukawa, unstowed the NanoRacks External Platform and then mounted a pressure management device to it before configuring power and data cables.

Unlocking the Secrets of Stem Cells in Zero Gravity

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Embryonic Stem Cell Illustration

The Expedition 70 crew at the International Space Station embarked on a busy week filled with stem cell research and preparations for the arrival of the Progress 87 cargo craft.

A busy week of science and prep for an upcoming cargo delivery kicked off aboard the International Space Station on Monday as the Expedition 70 crew set its sights on new stem cell research and orbital training.

Two cosmonauts, Flight Engineers Oleg Kononenko and Nikolai Chub, are gearing up to be on duty monitoring the automated docking of the Progress 87 cargo craft, which is scheduled to launch from the Baikonur Cosmodrome in Kazakhstan at 10:25 p.m. EST on Wednesday, February 14. Loaded with nearly three tons of food, fuel, and supplies, Progress will dock to the station around 1:12 a.m. Saturday, February 17. In preparation of the upcoming cargo delivery, the cosmonauts trained on the telerobotically operated rendezvous unit, or TORU, which allows them to remotely control an arriving spacecraft in the unlikely event it could not automatically dock.

Meanwhile, the Progress 85 cargo craft, which arrived to the station about six months ago, will undock from the station at 9:09 p.m. Monday, February 12 About three hours later, it will be commanded to deorbit before harmlessly burning up over the Pacific Ocean.

Advancements in Stem Cell Research

While training for the upcoming mission was underway, two NASA Flight Engineers, Jasmin Moghbeli and Loral O’Hara, focused a majority of their day on the Mesenchymal Stem Cells in Microgravity Induced Bone Loss (MABL-A) investigation. MABL-A, which was delivered aboard Northrop Grumman’s 20th Commercial Resupply Mission nearly two weeks ago, assesses the effects of microgravity on bone marrow stem cells. The duo worked separately throughout the day to sample BioCells inside the habitat with assistance from JAXA (Japan Aerospace Exploration Agency) Flight Engineer Satoshi Furukawa.

NASA astronaut and Expedition 70 Flight Engineer Jasmin Moghbeli works inside the Life Science Glovebox for the Microgravity Associated Bone Loss-A investigation. She was processing bone cell samples obtained from human donors on Earth and exploring space-caused bone loss. Results may help doctors learn how to protect and treat astronauts on long-term missions and inform treatments for bone conditions on Earth. Credit: SciTechDaily.com

Orbital Training and Equipment Setup

Later on, Moghbeli donned the Bio-Monitor garment and headband, which monitors and records vital signs while crew members perform daily activities. Afterward, she was joined by Furukawa, ESA (European Space Agency) Commander Andreas Mogensen, and Roscosmos Flight Engineer Konstantin Borisov to complete orbital training in the unlikely event an emergency were to occur on station.

Near the end of the day, Mogensen, with assistance from Furukawa, unstowed the NanoRacks External Platform and then mounted a pressure management device to it before configuring power and data cables.

Scientists Engineer Human T Cells 100x More Potent at Killing Cancer Cells.

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Scientists have identified a mutation that significantly boosts the cancer-fighting ability of engineered T cells without causing toxicity. This innovative approach, which works against multiple tumor types in mice, could lead to effective treatments for previously incurable cancers and is advancing toward human trials.

Researchers have engineered T cells with a cancer-derived mutation, boosting their potency against tumors over 100-fold without toxicity, marking a significant advancement in immunotherapy that could extend its effectiveness to solid tumors.

  • Current immunotherapies work only against cancers of the blood and bone marrow
  • T cells engineered by Northwestern and UCSF were able to kill tumors derived from skin, lung, and stomach in mice
  • Cell therapies can provide long-term immunity against cancer

Harnessing Cancer’s Strength for Immunotherapy

Scientists at the UC San Francisco (UCSF) and Northwestern Medicine may have found a way around the limitations of engineered T cells by borrowing a few tricks from cancer itself.

By studying mutations in malignant T cells that cause lymphoma, they zeroed in on one that imparted exceptional potency to engineered T cells. Inserting a gene encoding this unique mutation into normal human T cells made them more than 100 times more potent at killing cancer cells without any signs of becoming toxic.

While current immunotherapies work only against cancers of the blood and bone marrow, the T cells engineered by Northwestern and UCSF were able to kill tumors derived from skin, lung and stomach in mice. The team has already begun working toward testing this new approach in people.

Nature-Inspired T Cell Enhancement

“We used nature’s roadmap to make better T cell therapies,” said Dr. Jaehyuk Choi, an associate professor of dermatology and of biochemistry and molecular genetics at Northwestern University Feinberg School of Medicine. “The superpower that makes cancer cells so strong can be transferred into T cell therapies to make them powerful enough to eliminate what were once incurable cancers.”

“Mutations underlying the resilience and adaptability of cancer cells can super-charge T cells to survive and thrive in the harsh conditions that tumors create,” said Kole Roybal, associate professor of microbiology and immunology at UCSF, center director for the Parker Institute for Cancer Immunotherapy Center at UCSF, and a member of the Gladstone Institute of Genomic Immunology.

The study was published on February 7 in the journal Nature.

Overcoming Tumor Defense Mechanisms

Creating effective immunotherapies has proven difficult against most cancers because the tumor creates an environment focused on sustaining itself, redirecting resources like oxygen and nutrients for its own benefit. Often, tumors hijack the body’s immune system, causing it to defend the cancer, instead of attacking it.

Not only does this impair the ability of regular T cells to target cancer cells, it undermines the effectiveness of the engineered T cells that are used in immunotherapies, which quickly tire against the tumor’s defenses.

“For cell-based treatments to work under these conditions,” Roybal said, “we need to give healthy T cells abilities that are beyond what they can naturally achieve.”

The Northwestern and UCSF teams screened 71 mutations found in patients with T cell lymphoma and identified which ones could enhance engineered T cell therapies in mouse tumor models. Eventually, they isolated one that proved both potent and non-toxic, subjecting it to a rigorous set of safety tests.

“Our discoveries empower T cells to kill multiple cancer types,” said Choi, a member of the Robert H. Lurie Comprehensive Cancer Center of Northwestern University. “This approach performs better than anything we’ve seen before.” Their discoveries can be incorporated into treatments for many types of cancer, the scientists said.

“T cells have the potential to offer cures to people who are heavily pretreated and have a poor prognosis,” Choi said. “Cell therapies are living drugs, because they live and grow inside the patient and can provide long-term immunity against cancer.”

A New Frontier in Cancer Treatment

In collaboration with the Parker Institute for Cancer Immunotherapy and Venrock, Roybal and Choi are building a new company, Moonlight Bio, to realize the potential of their groundbreaking approach. They are currently developing a cancer therapy that they hope to begin testing in people within the next few years.

“We see this as the starting point,” Roybal said. “There’s so much to learn from nature about how we can enhance these cells and tailor them to different types of diseases.”

Obesity disrupts mitochondria, reduces fat-burning

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At a Glance

  • Scientists identified a protein that triggers changes in mitochondria that lead to reduced fat-burning to promote weight gain in mice fed a high-fat diet.
  • The findings may point to potential new avenues for treating or preventing obesity in people.

Mitochondria surrounding lipid droplets appear brighter in right panel.

A high-fat diet caused mitochondria (purple) in white fat cells to become fragmented and less effective at burning energy (left panel). In mice that lacked RalA, the absence of RalA prevented this fragmentation (right panel) and preserved the energy production of mitochondria. The large lipid (fat) droplets in fat cells appear green.

Adipose tissue, or body fat, plays a key role in maintaining our health. It helps to store and supply energy, regulate body temperature, and send hormone signals that affect many body functions. But when a person develops obesity, it leads to expansion of a type of fat called white adipose tissue, along with increased inflammation and metabolic changes.

Mitochondria, the energy-generating structures found within cells, are dynamic—that is, they can fuse, change shape, and divide. These changes affect how much energy mitochondria can burn. Some studies have found that obesity can alter these dynamics and cause mitochondria to fragment, making it more difficult for fat cells to burn energy. This might help explain why it can be hard for people with obesity to lose weight. The breakdown of mitochondria has also been tied to insulin resistance in obesity. And insulin resistance is associated with diabetes and other metabolic conditions. But the underlying connections between obesity, mitochondria, and white fat have been unclear.

A research team led by Dr. Alan Saltiel at the University of California, San Diego, had previously shown that a protein called RalA could be activated by insulin in fat cells and promote glucose uptake by brown fat. The team suspected that study of RalA might also give insights into the mitochondrial changes linked to obesity.

To investigate, the researchers fed mice a high-fat diet (about 60% fat) for 8 to 12 weeks. They then examined its effects on RalA and the mitochondria in fat cells. Results were reported on January 29, 2024, in Nature Metabolism.

The researchers found that the high-fat diet caused the mitochondria in white fat tissue to divide into many smaller pieces. As a result, the mitochondria became less effective at burning energy. The high-fat diet also boosted levels of RalA in white fat. These changes weren’t seen in brown fat tissue. The results hinted that higher RalA activity might be the culprit behind many metabolic problems seen in obesity.

To gain insights into the effects of RalA activation, the team looked at what happens in the protein’s absence. They created genetically altered mice that lacked the RalA-producing gene in fat tissues. When given a high-fat diet, mice without RalA in their white fat tissue were protected against diet-induced weight gain and obesity. They had additional metabolic improvements as well. These included better liver function and glucose tolerance, and energy expenditure similar to mice fed a regular diet. Absence of RalA also prevented fragmentation of mitochondria in mice fed a high-fat-diet, thereby protecting mitochondria’s fat-burning functions.

Further analysis showed how RalA activity leads to changes in mitochondria dynamics. The researchers found the same mechanisms in white fat from people. They also found that the activity of a key protein in the process was associated with human obesity. More study will be needed to understand how a high-fat diet raises levels of RalA in white fat in the first place.

“In essence, chronic activation of RalA appears to play a critical role in suppressing energy expenditure in obese adipose tissue,” Saltiel says. “By understanding this mechanism, we’re one step closer to developing targeted therapies that could address weight gain and associated metabolic dysfunctions by increasing fat burning.”