Stanford Medicine study identifies immune switch critical to autoimmunity, cancer

Edgar Engleman, MD, professor of pathology
Photo Credit: Courtesy of Stanford School of Medicine

A single signaling pathway controls whether immune cells attack or befriend cells they encounter while patrolling our bodies, researchers at Stanford Medicine have found. Manipulating this pathway could allow researchers to toggle the immune response to treat many types of diseases, including cancers, autoimmune disorders and those that require organ transplants.

The research, which was conducted in mice, illuminates the mechanism of an important immune function that prevents inappropriate attacks on healthy tissue. Called peripheral immune tolerance, the key cellular players, known as regulatory T cells (or Tregs, pronounced “tee-regs”), were first described in the late 1990s in a series of discoveries that were recently recognized with the 2025 Nobel Prize in physiology or medicine.

A platform to test new cancer treatments

Differentiated hepatic cells growing in a flask re-gain the appearance of cells present in liver.
Image Credit: © FAMOL, UNIGE

Overcoming acquired treatment resistance is one of the major challenges in the fight against cancer. While combination therapies hold promise, their toxicity to healthy tissue remains a major hurdle. To anticipate these risks, researchers at the University of Geneva (UNIGE) have developed in vitro models of the kidneys, liver, and heart – three organs particularly sensitive to such therapies. This fast, animal-free approach paves the way for safer evaluation of new treatments. The findings are published in Biomedicine & Pharmacotherapy. 

Recent advances in immunotherapy, targeted therapies, and gene therapies have significantly improved survival rates for patients with cancer. However, over time, many tumors develop resistance to these treatments, undermining their effectiveness. This phenomenon, known as ‘acquired resistance’, has become one of the major challenges in oncology. 

Storms in the Southern Ocean mitigates global warming

Visible satellite image showing storms sweeping across the Southern Ocean on 4 January 2019.
Photo Credit: NASA Worldview Snapshot

Intense storms that sweep over the Southern Ocean enable the ocean to absorb more heat from the atmosphere. New research from the University of Gothenburg shows that today’s climate models underestimate how storms mix the ocean and thereby give less reliable future projections of our climate. 

The Southern Ocean is a vast expanse of ocean encircling the Antarctic continent, regulating Earth’s climate by moving heat, carbon, and nutrients out in the world’s oceans. 

It provides a critical climate service by absorbing over 75 per cent of the excess heat generated by humans globally. The Southern Ocean’s capacity to reduce climate warming depends on how efficiently it can absorb heat from our atmosphere.  

Identical micro-animals live in two isolated deep-sea environments. How is that possible?

The researchers traveled on the research vessel Polarstern to South Sandwich Trench where they collected sediment samples.
Photo Credit: ©Anni Glud/SDU

Scientific Frontline: "At a Glance" Summary

• Main Discovery: Identical genera of microscopic nematodes populate two isolated deep-sea trenches separated by 17,000 km, despite the organisms possessing negligible mobility.
• Methodology: Scientists analyzed environmental DNA (eDNA) extracted from sediment samples collected at nine distinct sites within the Aleutian and South Sandwich Trenches via the research vessel Polarstern.
• Key Data: Analysis revealed three shared genera—Halalaimus, Desmoscolex, and Chromadorita—present in densities of hundreds to thousands per 10 grams of sediment, among 58 total identified genera.
• Significance: The findings extend the "meiofauna paradox" to the deepest ocean zones, indicating that unknown mechanisms connect hadal environments previously thought to be biologically isolated.
• Future Application: These results will spur new research models regarding deep-sea dispersal mechanisms, focusing on geological events like sediment slides rather than biological migration.
• Branch of Science: Marine Biology and Ecology
• Additional Detail: Evidence suggests the shared genera are highly resilient, having adapted to chemically distinct habitats with varying carbon and nitrogen concentrations within each trench.

Immune system keeps mucosal fungi in check

The yeast fungus Candida albicans (blue) breaks out of human immune cells (red) by forming long thread-like cells called hyphae. The part of the hypha that has already left the immune cells is colored yellow.
Image Credit: Erik Böhm, Leibniz-HKI

The yeast Candida albicans colonizes mucosal surfaces and is usually harmless. However, under certain conditions it can cause dangerous infections. A research team at the University of Zurich has now discovered how the immune system prevents the transformation from a harmless colonizer to a pathogenic mode. This happens, among other things, by sequestering zinc. 

The microbiome not only consists of bacteria, but also of fungi. Most of them support human and animal health. However, some fungi also have pathogenic potential. For instance, the yeast Candida albicans can grow in an uncontrolled manner on the oral mucosa, causing oral thrush. 

In severe cases by growing in a filamentous form, it can enter the bloodstream and cause systemic infections, which account for over one million deaths per year. This happens primarily in people with a weakened immune system on intensive care units, for instance individuals who are immunosuppressed because of a transplantation or cancer. 

Surfing on the waves of the microcosm

A particle (red sphere) is guided from left to its destination (right) using a laser trap (double-cone) by means of a protocol developed in the study, which is described by the parameter λ. A known time-dependent external force field F (t) acts on this environment. The optimised protocol exploits this force field in a way that extracts the maximum amount of work. This can be applied to various external fields, to active particles and to micro-robot transport problems. 
Image Credit: HHU/Kristian S. Olsen

Conditions can get rough in the micro- and nanoworld. To ensure that e.g. nutrients can still be optimally transported within cells, the minuscule transporters involved need to respond to the fluctuating environment. Physicists at Heinrich Heine University Düsseldorf (HHU) and Tel Aviv University in Israel have used model calculations to examine how this can succeed. They have now published their results – which could also be relevant for future microscopic machines – in the scientific journal Nature Communications. 

When planning an ocean crossing, sailors seek a course, which makes optimum use of favorable wind and ocean currents, and maneuver to save time and energy. They also react to random fluctuations in wind and currents and take advantage of fair winds and waves. Such considerations regarding energy costs are also important for transport processes at the micro- and nanoscale. For example, molecular motors should use as little energy as possible when transporting nutrients from A to B between and within biological cells.  

Scientists create stable, switchable vortex knots inside liquid crystals

Vortex knots inside a chiral nematic liquid crystal
Image Credit: Ivan Smalyukh

The knots in your shoelaces are familiar, but can you imagine knots made from light, water, or from the structured fluids that make LCD screens shine? 

They exist, and in a new Nature Physics study, researchers created particle-like so-called “vortex knots” inside chiral nematic liquid crystals, a twisted fluid like those used in LCD screens. For the first time, these knots are stable and could be reversibly switched between different knotted forms, using electric pulses to fuse and split them. 

“These particle-like topological objects in liquid crystals share the same kind of topology found in theoretical models of glueballs, experimentally-elusive theoretical subatomic particles in high-energy physics, in hopfions and heliknotons studied in light, magnetic materials, and in vortex knots found across many other systems,” explains Ivan Smalyukh, director of the Hiroshima University WPI-SKCM² Satellite at the University of Colorado Boulder and a professor in CU Boulder’s Department of Physics. 

Rice researchers uncover the hidden physics of knot formation in fluids

From left to right, top to bottom: Sibani Lisa Biswal, Fred MacKintosh, Lucas H.P. Cunha and Luca Tubiana.
Photo Credit: Courtesy of Rice University

Knots are everywhere — from tangled headphones to DNA strands packed inside viruses — but how an isolated filament can knot itself without collisions or external agitation has remained a longstanding puzzle in soft-matter physics.

Now, a team of researchers at Rice University, Georgetown University and the University of Trento in Italy has uncovered a surprising physical mechanism that explains how a single filament, even one too short or too stiff to easily wrap around itself, can form a knot while sinking through a fluid under strong gravitational forces. The discovery, published in Physical Review Letters, provides new insight into the physics of polymer dynamics, with implications ranging from understanding how DNA behaves under confinement to designing next-generation soft materials and nanostructures.

“It is inherently difficult for a single, isolated filament to knot on its own,” said Sibani Lisa Biswal, corresponding author, chair of Rice’s Department of Chemical and Biomolecular Engineering and the William M. McCardell Professor in Chemical Engineering. “What’s remarkable about this study is that it shows a surprisingly simple and elegant mechanism that allows a filament to form a knot purely because of stochastic forces as it sediments through a fluid under strong gravitational forces.”

AI helps explain how covert attention works and uncovers new neuron types

Image Credit: Scientific Frontline / AI generated

Shifting focus on a visual scene without moving our eyes — think driving or reading a room for the reaction to your joke — is a behavior known as covert attention. We do it all the time, but little is known about its neurophysiological foundation. Now, using convolutional neural networks (CNNs), UC Santa Barbara researchers Sudhanshu Srivastava, Miguel Eckstein and William Wang have uncovered the underpinnings of covert attention and, in the process, have found new, emergent neuron types, which they confirmed in real life using data from mouse brain studies. 

“This is a clear case of AI advancing neuroscience, cognitive sciences and psychology,” said Srivastava, a former graduate student in the lab of Eckstein, now a postdoctoral researcher at UC San Diego. 

Climate shapes arms race between ants and their social parasites

The "slave-making ant" Temnothorax americanus (left) and its host Temnothorax longispinosus
Photo Credit: ©: Romain Libbrecht

The battle between ant hosts and their social parasites is strongly influenced by climate. Temperature and humidity shape how the ants behave, communicate, and even evolve — while host and parasite respond with very different genetic strategies. These are the findings of two recent studies in which researchers at Johannes Gutenberg University Mainz (JGU) and the Senckenberg Biodiversity and Climate Research Centre combined behavioral experiments with state-of-the-art genomic analyses. "Climate clearly explains the variation in host and parasite behavior better than parasite prevalence itself," says Professor Susanne Foitzik, senior author of both studies and chair of Behavioral Ecology and Social Evolution at JGU.

In the first study, published in the Journal of Evolutionary Biology, the team examined a parasite, the so-called "slave-making ant" Temnothorax americanus, and its host, the ant Temnothorax longispinosus. The social parasite invades host nests and steals their brood, which later grows up to work for the parasite colony – an extraordinary form of social parasitism. The researchers focused on how the ants' behavior and chemical communication vary across different climates. By comparing ten natural populations along a 1,000‑kilometer north-south gradient in the United States, they found that climate influenced the conflict more strongly than the local frequency of parasite colonies.