An edible biofilm, obtained from agricultural and fishing waste and developed by researchers at the São Carlos Institute of Chemistry of the University of São Paulo (IQSC-USP) in Brazil, allows the shelf life of strawberries (Fragaria x ananassa Duch.) to be extended.

In laboratory tests, the researchers found that over 12 days of refrigerated storage, the fruit coated with the film lost 11% weight and took between 6 and 8 days to start becoming contaminated with fungi, compared to 4 days for fruit not covered with the material.

The results of the work, carried out in collaboration with researchers from EMBRAPA Instrumentation and the Federal University of São Carlos (UFSCar), are published in the journal Food Chemistry.

“By applying the coating, it was possible to double the shelf life of strawberries kept under refrigeration and delay the dehydration of the fruit, while preserving the taste, texture and volatile compounds that give the fruit its characteristic aroma,” Mirella Romanelli Vicente Bertolo, first author of the study and a postdoctoral researcher at EMBRAPA Instrumentation, says.

The work began during Bertolo’s doctoral studies at IQSC-USP under the supervision of Professor Stanislau Bogusz Junior. During their research, they developed a technique that allowed them to extract 84.2% more antioxidants—substances with preservative properties—from the peel of pomegranate (Punica granatum L.) using natural deep eutectic solvents (NADES).

“More than 40% of the pomegranate, depending on the variety, is made up of peel, which is wasted. Our idea was to use this waste to obtain extracts rich in phenolic compounds with antioxidant and antimicrobial activities,” says Bogusz.

With the success of developing the extraction method, the researchers decided to test the hypothesis of incorporating the antioxidants in pomegranate into coatings based on gelatin and chitosan—a polymer (natural polysaccharide) found in the skeletons of crustaceans such as shrimp—to develop a protective film for fruit.

“We chose to use chitosan extracted from squid glia [inner shells] through a process of deacetylation of the chitin found in this mollusk, because it doesn’t have the problem of allergenicity like that obtained from shrimp. And we combined this material with another polymer, in this case gelatin, to improve its mechanical properties,” explains Bogusz.

Highly perishable fruit

The strawberry was chosen as a model system to test the effectiveness of the biofilm because it is one of the items with the highest loss rates in Brazilian supermarkets due to its perishability and short shelf life of about less than seven days under refrigeration.

“The strawberry is a fruit that has very high respiratory activity and a very low pH [acidity]. It’s therefore very susceptible to microbial attack. It’s also very moist and the fruit is small. Based on this, we hypothesized that if the material we developed worked, it’d be effective on any other fruit,” says Bogusz.

To test this hypothesis, the researchers coated strawberries with the edible film by immersion and evaluated the effects of the material on the physicochemical, microbiological and volatile profile and sensory characteristics of the fruit over 12 days of refrigerated storage.

The results indicate that the material forms a film on the surface of the fruit that acts as a barrier to the passage of microorganisms, moisture loss and gas exchange, modifying the strawberry’s respiration. In this way, the coating slows down the metabolism of the fruit during the post-harvest period, thereby increasing its shelf life and preserving the color, firmness and bioactive compounds of the fruit.

“We found that the film made it possible to maintain the texture, delay contamination by microorganisms and reduce the loss of fruit mass, which is observed when the strawberry shrivels. This happens very often with uncoated fruit because it easily loses water and dehydrates,” says Bertolo.

According to the researcher, the film also made it possible to reduce the severity of fungal damage and improve the volatile profile of the fruit. “The material made it possible to preserve 40% more of the compounds responsible for the fruit’s aroma,” says Bertolo.

The biofilm also didn’t interfere with the sensory characteristics of the fruit, such as flavor, as confirmed by sensory analysis tests conducted with undergraduate chemistry students at IQSC-USP.

“The results of the tests showed that there were no differences in the taste, aroma or visual characteristics of strawberries coated with the material compared to strawberries without the film,” says Bertolo.

The researchers have filed a patent application for the formulation and intend to license the technology to interested companies.

Economic analyses indicate that the coating could cost an estimated BRL 0.15 per fruit.

“This is a cost that consumers may be willing to pay for fruit with a longer shelf life and greater usage,” Bertolo estimates.

Under the right conditions, duckweed essentially farms itself. Wastewater, ponds, puddles, swamps—you name it. If there’s enough sunlight and carbon dioxide, the aquatic plant can grow freely. But that’s not all that makes it intriguing. Packed inside duckweed’s tiny fronds is enormous potential as a soil enricher, a fuel source, protein-rich foods, and more. New findings at Cold Spring Harbor Laboratory (CSHL) could help bring all that potential to life. The research is published in the journal Current Biology.

CSHL Professor and HHMI Investigator Rob Martienssen and Computational Analyst Evan Ernst started working with duckweed over 15 years ago. They see their latest research as one of the most important and eye-opening studies on the plant to date. The team has developed new genome sequences for five duckweed species. The sequences reveal several genes that—when present or absent—may be behind the plant’s unique traits and versatility.

Martienssen explains, “The use of cutting-edge technology allowed us to make a catalog of genes that was extremely accurate. We could tell exactly which genes were there and which were not. A lot of genes that are missing are responsible for features of the plant—open stomata or the lack of roots. We could identify genes that were responsible for each trait.”

Stomata are pores on the surface of plants. They’re crucial for taking in carbon dioxide and releasing oxygen. Open stomata allow for greater intake, making them valuable for carbon capture technology. A lack of roots in some species further increases duckweed’s potential, making it easier for the plant to thrive in any watery environment.

Other species possess traits that showcase duckweed’s potential as a food and fuel source. Some traits promote high protein production, allowing for use as animal feed. Others promote starch accumulation, making the plant ripe for biofuel production. Several industries have taken notice. For now, they’re mostly concerned with the duckweed growing in their backyards.

Ernst explains, “Duckweed agriculture is in a nascent stage. Commercial growers are working with different species in the field, evaluating them in their own local situation. There’s so much variation within one species of duckweed—as much as you can find across all the species. So, having multiple genomes for multiple species is critical.”

Martienssen and Ernst hope their genomes will open the door to a new world of commercial applications. That said, their research may tell us as much about the plant’s past. Their study hints at how duckweed split off into different species 59 million years ago. Earth’s climate was quite extreme back then, so duckweed’s genes just might say something about the planet’s future, too.

Researchers at the Hong Kong University of Science and Technology (HKUST) have developed a cutting-edge AI-assisted 3D food printing solution that combines printing with infrared cooking, paving the way for safer, more efficient, and visually appealing food production. The study, “Advanced 3D Food Printing with Simultaneous Cooking and Generative AI Design,” was recently published in the journal Advanced Materials.

Traditional 3D food printing methods often require additional postprocessing steps, which can have unappealing food ingredients, imperfect shapes, and even potential microbial contamination.

To address these challenges, the team from the Division of Integrative Systems and Design (ISD) at HKUST has developed an AI-enhanced system that combines extrusion-based printing with simultaneous infrared heating for on-the-fly cooking of intricate starch-based foods. Using graphene heaters for cooking, they precisely controlled the cooking process, ensuring that starch-based food items retain their intended shape and quality.

The system is supported by AI-assisted design, which employs generative algorithms and Python scripts to craft intricate food patterns. By leveraging AI, the design process became accessible to even computer novices.

The research tackles issues such as shape retention and contamination risks and opens up exciting prospects for tailored nutrition—benefiting individuals with special dietary needs, including patients with dysphagia. From enhancing meal customization in elderly care centers and central kitchens to meeting special dietary needs and enabling creative culinary experiences in restaurants, the technology offers a versatile solution for various sectors.

“With its potential to streamline food production processes, improve food quality, and cater to individual preferences, this innovation can transform how food is prepared and served in diverse settings, paving the way for a future where personalized and visually appealing food creations are more accessible than ever before,” said Prof. Mitch Li Guijun, Assistant Professor of ISD, who led the research team.

“We’re excited about the potential of this technology to deliver customized, safe, and delicious food with a process that is both efficient and accessible. It represents a significant step forward in how we think about food creation,” Prof. Li added.

Connie Lee Kong-Wai, the paper’s first author and a Ph.D. student at HKUST, said, “We’ve reimagined what 3D food printing can achieve by merging technology and culinary creativity. Our cutting-edge integrative 3D food printing technology can potentially revolutionize personalized food creation.”

The research represents a collaborative effort spanning user-centric design, mechanical engineering, food science, chemistry, and AI. This cross-disciplinary approach brought together diverse expertise to tackle the complex challenges associated with 3D food printing.

Looking ahead, the team plans to refine the technology by examining the preservation of heat-sensitive vitamins and optimizing starch digestibility. Future studies will also focus on consumer acceptance through sensory evaluations involving target users such as children or hospital caretakers, ensuring that the system is ready for real-world applications.

Living cells are bustling with molecular machines that constantly process energy, matter, and information. Among these machines, proteins stand out, with enzymes being the most notable. These catalytic entities dramatically accelerate essential metabolic reactions by many orders of magnitude, facilitating the very processes that sustain life. While it has long been acknowledged that enzymes undergo movements during their catalytic cycles, measuring and predicting these internal motions and forces has proven extremely challenging.

A new study published in the journal Nature Physics addresses that challenge. It is the result of an international collaboration, led by Professor Tsvi Tlusty from the Department of Physics at UNIST and Professor Elisha Moses from the Physics Department at the Weizmann Institute of Science, Israel.

The collaboration integrated artificial intelligence (AI) models with molecular dynamics simulations to predict the internal dynamics of enzymes, alongside an innovative “nano-rheology” technique to measure these dynamics with unprecedented accuracy.

The computational and experimental results culminated in the development of a new viscoelastic model of enzymes, elucidating the intertwined effects of elastic forces arising from stretching or twisting molecular bonds and friction forces (viscosity) associated with bond breaking and reforming.

“Finally, this novel physical model can explain how subtle, nanoscale motions and forces within enzymes impact their biological functions. It allows us to perceive proteins as soft robots or programmable active matter,” said Professor Tlusty.

For years, scientists believed that our first memories vanished because the brain wasn’t developed enough to store them. But groundbreaking Yale research suggests otherwise.

Infants can encode and recall memories—even if we can’t access them later in life. By using brain scans and eye-tracking, researchers found that when an infant’s hippocampus is more active, they are more likely to remember an image. This discovery challenges the idea of “infantile amnesia” and raises a fascinating question: Could our earliest experiences still be hidden deep in our minds, just beyond reach?

Memories from Infancy: A Surprising Discovery

We learn an incredible amount in our earliest years, yet as adults, we struggle to recall specific events from that time. Scientists have long believed this is because the hippocampus, the part of the brain responsible for memory, is still developing throughout childhood and isn’t capable of storing memories in infancy. However, new research from Yale challenges this idea.

In a recent study, researchers presented infants with new images and later tested their recognition. They found that when an infant’s hippocampus was more active upon first seeing an image, the child was more likely to recognize it later.

Published on March 20 in Science, these findings suggest that memories can indeed be encoded in the brain during infancy. The next step for researchers is to explore what happens to these early memories over time.

Infantile Amnesia: The Mystery of Forgotten Early Memories

The inability to recall specific experiences from the first years of life is known as “infantile amnesia,” but studying it presents unique challenges.

“The hallmark of these types of memories, which we call episodic memories, is that you can describe them to others, but that’s off the table when you’re dealing with pre-verbal infants,” said Nick Turk-Browne, professor of psychology in Yale’s Faculty of Arts and Sciences, director of Yale’s Wu Tsai Institute, and senior author of the study.

How Scientists Measure Memory in Babies

For the study, the researchers wanted to identify a robust way to test infants’ episodic memories. The team, led by Tristan Yates, a graduate student at the time and now a postdoctoral researcher at Columbia University, used an approach in which they showed infants aged four months to two years an image of a new face, object, or scene. Later, after the infants had seen several other images, the researchers showed them a previously seen image next to a new one.

“When babies have seen something just once before, we expect them to look at it more when they see it again,” said Turk-Browne. “So in this task, if an infant stares at the previously seen image more than the new one next to it, that can be interpreted as the baby recognizing it as familiar.”

Hippocampal Activity: A Key to Infant Memory

In the new study, the research team, which over the past decade has pioneered methods for conducting functional magnetic resonance imaging (fMRI) with awake infants (which has historically been difficult because of infants’ short attention spans and inability to stay still or follow directions), measured activity in the infants’ hippocampus while they viewed the images.

Specifically, the researchers assessed whether hippocampal activity was related to the strength of an infant’s memories. They found that the greater the activity in the hippocampus when an infant was looking at a new image, the longer the infant looked at it when it reappeared later. And the posterior part of the hippocampus (the portion closer to the back of the head) where encoding activity was strongest is the same area that’s most associated with episodic memory in adults.

These findings were true across the whole sample of 26 infants, but they were strongest among those older than 12 months (half of the sample group). This age effect is leading to a more complete theory of how the hippocampus develops to support learning and memory, said Turk-Browne.

Different Memory Pathways: Statistical Learning vs. Episodic Memory

Previously, the research team found that the hippocampus of infants as young as three months old displayed a different type of memory called “statistical learning.” While episodic memory deals with specific events, like, say, sharing a Thai meal with out-of-town visitors last night, statistical learning is about extracting patterns across events, such as what restaurants look like, in which neighborhoods certain cuisines are found, or the typical cadence of being seated and served.

These two types of memories use different neuronal pathways in the hippocampus. And in past animal studies, researchers have shown that the statistical learning pathway, which is found in the more anterior part of the hippocampus (the area closer to the front of the head), develops earlier than that of episodic memory. Therefore, Turk-Browne suspected that episodic memory may appear later in infancy, around one year or older. He argues that this developmental progression makes sense when thinking about the needs of infants.

“Statistical learning is about extracting the structure in the world around us,” he said. “This is critical for the development of language, vision, concepts, and more. So it’s understandable why statistical learning may come into play earlier than episodic memory.”

What Happens to Early Memories?

Even still, the research team’s latest study shows that episodic memories can be encoded by the hippocampus earlier than previously thought, long before the earliest memories we can report as adults. So, what happens to these memories?

There are a few possibilities, says Turk-Browne. One is that the memories may not be converted into long-term storage and thus simply don’t last long. Another is that the memories are still there long after encoding and we just can’t access them. And Turk-Browne suspects it may be the latter.

In ongoing work, Turk-Browne’s team is testing whether infants, toddlers, and children can remember home videos taken from their perspective as (younger) babies, with tentative pilot results showing that these memories might persist until preschool age before fading.

Could Early Memories Be Retrieved?

The new findings, led by Yates, provides an important connection.

“Tristan’s work in humans is remarkably compatible with recent animal evidence that infantile amnesia is a retrieval problem,” said Turk-Browne. “We’re working to track the durability of hippocampal memories across childhood and even beginning to entertain the radical, almost sci-fi possibility that they may endure in some form into adulthood, despite being inaccessible.”

FORT BEND COUNTY, Texas — Fort Bend County Health and Human Services on Sunday announced that it has confirmed its first case of the measles in 2025.

The county said the case is in a woman between the ages of 50 and 60. They said the case is associated with international travel and is not connected to the West Texas outbreak.

“Your safety and well-being remain my top priority,” said Fort Bend County Judge KP George. “I urge all residents to check their immunization records, get vaccinated if necessary and stay vigilant for symptoms. Together, we can protect our families, neighbors and the greater Fort Bend community.”

Researchers from São Paulo State University (UNESP), at its Tupã campus in Brazil, have developed and tested a new geospatial intelligence methodology that can contribute more quickly and accurately to land use management and territorial planning projects.

With this tool, it was possible to precisely delineate areas of the Amazon rainforest, Cerrado vegetation (the Brazilian savannah-like biome), pastures and agricultural crops in a double-cropping system, something that can provide support for public policies aimed at agricultural production and environmental conservation.

The research is published in the journal AgriEngineering.

By combining data cube architecture (ready for analysis), disseminated in Brazil through the Brazil Data Cube project, led by the National Institute for Space Research (INPE), and the Geobia (Geographic Object-Based Image Analysis) approach, the scientists were able to identify vegetation and double cropping—for example, soy and corn—over the course of a harvest in the state of Mato Grosso. They used a time series of satellite images from NASA’s Modis (Moderate Resolution Imaging Spectroradiometer) sensor.

The results showed that the proposed combination, coupled with machine learning (artificial intelligence) algorithms, achieved 95% mapping accuracy.

Geobiology is a technique that allows satellite images to be processed using segmentations that group similar pixels into geo-objects and study their characteristics, such as shape, texture, and reflectance. In many cases, this allows for a more realistic interpretation. Data cubes, on the other hand, store information in dimensions—time and place—making it easier to aggregate and visualize information related to a specific location in a specific time period, such as crop areas in a harvest year.

Currently, mapping uses pixel image analysis in isolation, which ends up creating edge problems with blurring in some areas.

“Scientific work has highlighted spectral confusion in border zones between different land uses as an area for improvement. So we decided to segment the images and evaluate the geographic object as the minimum unit of analysis, rather than the pixel. It’s as if the image were broken down and classified according to each piece,” Michel Eustáquio Dantas Chaves, professor at the Faculty of Science and Engineering of UNESP and corresponding author of the article, told Agência FAPESP.

“In this way, we were able to reduce recurring edge errors and accurately identify the targets, even with moderate spatial resolution.”

Chaves has been using data cube architecture for several years to develop tools that contribute to analyses focused on the advancement of the agricultural frontier, especially in the Cerrado.

According to the professor, the methodology can be replicated to evaluate images from other Earth observation satellites, such as Landsat and Sentinel, which provide data for scientific studies, mapping and monitoring. Images from both are now being processed by the team coordinated by the professor.

Application in practice

Mato Grosso leads national grain production with 31.4% of the country’s total, followed by the states of Paraná (12.8%) and Rio Grande do Sul (11.8%). The state is expected to reach 97.3 million tons in the 2024/2025 harvest, an increase of 4.4% over the previous harvest, according to the National Supply Company (CONAB). Almost half of this production (46.1 million tons) is expected to be soybeans.

In addition, Mato Grosso is one of the most biodiverse states in the country, containing parts of three of Brazil’s six biomes. Around 53% of its territory is in the Amazon, 40% in the Cerrado and 7% in the Pantanal.

Due to this heterogeneity of land uses and vegetation types in the territory, the researchers applied the new methodology in Mato Grosso using data from the 2016–2017 strategic harvest, in which Brazil produced 115 million tons of soybeans, of which 30.7 million tons were in the state. Land use classifications were associated with agricultural land (fallow-cotton, soybean-cotton, soybean-corn, soybean-fallow, soybean-millet and soybean-sunflower), as well as sugarcane crops, urban areas and water bodies.

The results showed an overall accuracy of 95%, demonstrating the potential of the approach to provide mapping that optimizes forest and agricultural land delineation.

“Since the approach manages to identify the targets in a consistent manner, the methodology can be applied to the estimation of areas within the same harvest, favoring productivity estimates; in territorial planning actions and anything that deals with land use and land cover for decision-making,” explains Chaves about the application of the tool.

The professor explains that the methodology also makes it possible to analyze disturbances in forests and other types of natural vegetation: “It’s quicker to detect deforestation than degradation. This method allowed us to detect these variations more quickly.”

In the article, the scientists pay tribute to Professor Ieda Del’Arco Sanches, a remote sensing researcher at INPE who died in January.

“This article is a way of thanking her for her teachings and following her legacy. Ieda always worked to accurately assess Earth’s surface and to treat the data ethically and responsibly, showing how they can contribute to the construction of public policies,” adds Chaves.

A recent study on cell-cultivated fish has produced promising results that could put seafood back on the menu for the three to five percent of the global population with severe food allergies.

JCU researchers at the College of Science and Engineering, in collaboration with JCU’s Tropical Futures Institute in Singapore, have found that cell-based fish can lead to the production of safer seafood products with vastly diminished allergy risks, after analysis of cultivated Japanese eel (Unagi) showed positive signs.

Seafood is a leading trigger of food-induced anaphylaxis in many regions worldwide.

Research presented at the recent World Allergy Congress revealed that fish allergens in the cultivated Unagi were more than 10-fold lower compared to conventional eel.

Head of JCU’s Molecular Allergy Research Laboratory (MARL), Professor Andreas L. Lopata, said the study is showing hugely promising results. The research began almost a decade ago working with children who had a clinical history of allergies to bony fish.

“We have a data bank of over 100 children with confirmed fish allergies, and we demonstrated that there is very little to no reactivity to the known fish allergens in the cell-cultivated fish,” Prof Lopata said. “The levels of allergens present in the cell-cultivated fish being so low was quite surprising to us.

“You’re basically taking stem cells from the fish, growing them in tissue culture to the size they are edible, and everyone told us it would basically be the same as the regular fish including any allergy risks.

“Instead, we found diminished risks, including a decrease of up to 1000-fold of the predominant fish allergen parvalbumin, and all of this was with no manipulation nor gene modification.”

The JCU team is partnering with the not-for-profit organization Good Food Institute (GFI) and the Singapore-based company Umami Bioworks on the project and Prof Lopata expects the product could be available to consumers within the next few years.

“Cultivated chicken and quail products are already available in Singapore and the Food Standards Australia and New Zealand (FSANZ) is expected to approve the first cultivated meat products soon,” he said. “Worldwide you are looking at 10–12 billion US dollars in investments in the alternative protein production industry in recent years.

“The first products will most likely be cultivated fish and seafood dumplings. They should have that same fish flavor and omega-3 fatty acid levels, which are very healthy, along with all the other components of regular fish and seafood.”

The process of having these products approved by the Singapore Food Agency has already begun, with an obvious focus on Food Safety.

“There can be uncertainties about allergenicity, but that’s where we come in, as experts in the field, really analyzing all proteins (the proteome) and then comparing particular allergen patterns to see if there could be anything unsafe for consumers,” Prof Lopata said.

Current genetic sequencing techniques can provide much information about the genetic makeup and activity in a sample, like a piece of tissue or a drop of blood. But they are unable to reveal where specific genetic sequences were located inside that sample, or their relationship to other genes and molecules, according to University of Chicago (UChicago) scientists, who say they are developing a novel method that overcomes these challenges.

By tagging each DNA or RNA molecule and allowing neighboring tags to interact, their approach constructs a molecular network that encodes their relative positions, creating a spatial map of genetic material. This technique, called volumetric DNA microscopy, creates a 3D image of an entire organism from the inside out, giving scientists an unprecedented view of genetic sequences and where they are located, down to individual cells, noted Joshua Weinstein, PhD, assistant professor of medicine and molecular engineering at UChicago.

In the article, “Spatial transcriptomic imaging of an intact organism using volumetric DNA microscopy” in Nature Biotechnology, Weinstein and postdoctoral scholar Nianchao Qian, PhD, used the technology to create a complete DNA image of a zebrafish embryo, a common model organism for studying development and neurobiology.

“It’s a level of biology that no one has ever seen before,” Weinstein said. “To be able to see that kind of a view of nature from within a specimen is exhilarating.”

Unlike traditional microscopes that use light or lenses, DNA microscopy creates images by calculating interactions among molecules, providing a new way to visualize genetic material in 3D. First, short DNA sequence tags called unique molecular identifiers (UMIs) are added to cells. They attach to DNA and RNA molecules and begin making copies of themselves. This starts a chemical reaction that creates new sequences, called unique event identifiers (UEIs), that are distinctive to each pairing.

It’s these pairings that help create the spatial map of where each genetic molecule is located. UMI pairs that are close together interact more frequently and generate more UEIs than those that are farther apart. Once the DNA and RNA are sequenced, a computational model reconstructs their original locations by analyzing the physical links between UMI tags, creating a spatial map of gene expression.
Weinstein compares the technique to using data from cell phones pinging each other to determine people’s location in a city. Knowing the cell phone number or IP address of each person is like knowing the genetic sequence of one molecule, but if you can layer on their interactions with other phones nearby, you can work out their locations too.

“We can do this with cell phones and people, so why not do that with molecules and cells,” he asked. “This turns the idea of imaging on its head. Rather than relying on an optical apparatus to shine light in, we can use biochemistry and DNA to form a massive network between molecules and encode their proximities to each other.”

DNA microscopy doesn’t rely on prior knowledge of the genome or shape of a specimen, so it could be useful for understanding genetic expression in unique, unknown contexts. Tumors generate countless new genetic mutations, for example, so the tool would be able to map out the tumor microenvironment and where it interacts with the immune system.

Immune cells interact with each other and respond to pathogens in context-specific ways, so DNA microscopy could help unravel those genetic mechanisms. Such applications could in turn guide more precise immunotherapy for cancer or tailor personalized vaccines.

“This is the critical foundation for being able to have truly comprehensive information about the ensemble of unique cells within the lymphatic system or tumor tissue,” pointed out Weinstein. “There has still been this major gap in technology for allowing us to understand idiosyncratic tissue, and that’s what we’re trying to fill in here.”

A preclinical study by researchers at Baylor College of Medicine has uncovered a mechanism that allows triple-negative breast cancer (TNBC) to develop resistance to immune checkpoint blockade (ICB) immunotherapy and to chemotherapy. The study, including tests in mouse models, showed that lipid accumulation in tumor cells and nearby immune cells promotes immune suppression. The results also indicated that disrupting lipid formulation reverses treatment resistance and the immunosuppressive microenvironment.

Xiang H.-F. Zhang, PhD, director of the Lester and Sue Smith Breast Center and professor of molecular and cellular biology at Baylor, is corresponding author of the team’s published study in Immunity, titled, “Tumor-derived arachidonic acid reprograms neutrophils to promote immune suppression and therapy resistance in triple-negative breast cancer,” in which the researchers concluded, “Overall, we demonstrate how lipid accumulation in TNBC cells leads to immune suppression and therapy resistance.”

Standard-of-care treatment for TNBC includes chemotherapy and immunotherapy, the authors explained. “For triple-negative breast cancer (TNBC), a combination of pembrolizumab (an anti-PD-1 antibody) and chemotherapies has been approved to treat advanced tumors in the neoadjuvant setting.” However, some initially responsive tumors still develop recurrences, “… suggesting acquired resistance mechanisms that remain poorly understood.”

Studying mouse models, Zhang and colleagues found that TNBC cells that survived treatment accumulated lipid droplets containing omega-6 fatty acids. Single-cell RNA sequencing revealed that neutrophils—a type of white blood cell—near the tumor cells also accumulated these lipids. “Single-cell RNA sequencing reveals a subset of neutrophils exhibiting a lipid-laden phenotype similar to adjacent tumor cells,” the investigators stated. “Mechanistically, tumor-derived extracellular vesicles carrying lipids, including arachidonic acid (AA), mediate neutrophil reprogramming.”

First author Liqun Yu, PhD, a postdoctoral fellow in the Zhang lab at Baylor, further explained, “We found the tumor cells give the lipid droplets to surrounding neutrophils. This shifted the function of the neutrophils from antitumor to tumor promotion.” The team in addition found that they could reverse therapy resistance and the immunosuppressive tumor microenvironment (TME) by disrupting lipid droplet formation. Blocking dietary intake of omega-6 fatty acids also resensitized the tumors to chemotherapy and immunotherapy.

“The prevailing perspective in our field has focused on the role of fatty acid metabolism in regulating the immune response and therapeutic response,” said Zhang, who is the William T. Butler, MD, Endowed Chair for Distinguished Faculty, and co-leader of the Breast Cancer Program at the Dan L Duncan Comprehensive Cancer Center at Baylor. “We found in this study that not only can fatty acids serve as an energy source, but they also are precursors of immunosuppressive signals the cancer cells can use to fight against our immune system.”

In their report, the team concluded, “Our findings suggest that the intake, processing, and storage of specific fatty acid in TNBC could alter their response to combined treatments involving ICB and chemotherapy. Our preclinical study offers potential strategies for pharmacological and dietary intervention to overcome therapeutic resistance, especially the acquired resistance.”

Zhang added, “We can advise patients to consume a diet low in omega-6 fatty acids, which is not significantly different from the general advice to lower red meat, fat, and sodium intake. We also are exploring therapeutic options to block fatty acid accumulation and immunosuppressive signals between the cancer cells and the neutrophils.”