Conventional mRNA vaccines, which proved central to the response to the Covid-19 pandemic, work by delivering instructions that tell cells to build a protein the immune system can learn to recognize. Unlike traditional vaccines that use a weakened or inactivated dose of a pathogen, RNA vaccines hand the body a molecular blueprint. The approach proved fast, flexible, and scalable, but conventional mRNA is transient: each molecule yields a limited amount of protein before it is degraded, which is why booster doses have been needed to sustain immunity.

Self-amplifying mRNA takes a different approach. Derived from the replication machinery of certain viruses, saRNA carries the genetic instructions not only for a target antigen but also for the machinery needed to copy itself inside host cells. In principle, a single saRNA molecule can generate many copies of itself and, in turn, far more antigen than a conventional mRNA dose. That amplification suggests that much smaller quantities of vaccine could deliver equivalent or longer-lasting protection, an advantage that could matter enormously for pandemic preparedness, for reaching populations in resource-limited settings, and for applications well beyond infectious disease.

The problem lies in what the amplification process leaves behind. As saRNA replicates inside a cell, it inevitably generates double-stranded RNA, or dsRNA, a molecular signature that mammalian cells treat as an alarm bell for viral infection. Antiviral defenses keyed to dsRNA respond by restricting the replication of the saRNA, making it less stable, less able to copy itself, and less effective at instructing the cell to produce the protein that trains the immune system. This built-in conflict between the vaccine and the cell’s own defenses has been a fundamental barrier limiting how potent an saRNA vaccine can be.

Dr Pierre Maillard and Dr Raul Yusef Sanchez David, scientists at Queen Mary University of London’s Blizard Institute, identified a way to ease that conflict. Their strategy involves NoV B2, a protein derived from Nodamura virus that is known to suppress RNA interference, one of the cell’s natural defenses against double-stranded RNA. When the researchers added NoV B2 alongside saRNA, the protein reduced the extent to which cells restricted the replicating vaccine RNA. The result was a marked increase in the amount of target protein produced, an effect the team observed in both stem cells and regular cells.

Crucially, the enhancement came without undermining the saRNA’s ability to stimulate the immune system. That balance matters, because any strategy that simply silenced cellular antiviral responses wholesale could risk blunting the very immune activation a vaccine depends on. By specifically tuning the intracellular response to double-stranded RNA, the Queen Mary team preserved the immunological signal while freeing the vaccine to amplify more effectively. The researchers describe the approach as tuning intracellular immunity, a phrase that captures the precision of the intervention.

The implications extend well beyond infectious disease. Because saRNA can drive sustained production of therapeutic proteins inside cells, the same technology underpins efforts in gene therapy, cancer immunotherapy, and protein replacement therapies. If the protein-boosting effect observed in the laboratory translates successfully in living organisms, the Queen Mary team’s innovation could make gene therapy safer and more affordable, make cancer vaccines more potent, and transform protein replacement therapy from a regimen of repeated infusions into a process in which a patient’s own body generates the medicine it needs.

Dr Maillard emphasized the broader significance of the result. The findings, he said, identify a strategy to overcome a fundamental barrier limiting self-amplifying vaccines, and if they translate successfully in vivo, they could open new possibilities for vaccine design as well as for gene therapies and cancer treatment. The team is now working with Queen Mary Innovation, the university’s technology transfer company, to find a commercial partner to help develop the technique for clinical use, a step that will determine how quickly the laboratory advance reaches patients.

The advance arrives at a moment of uncertainty for the field. The United States has announced 500 million dollars in cuts to mRNA vaccine research, a decision that sparked widespread concern across the global scientific and public health communities. Against that backdrop, the Queen Mary work has been framed by the university as evidence of the continued strength of the United Kingdom as a place to invest in impactful research and innovation. Whether saRNA vaccines fulfill their promise of protection at lower doses, rolled out further and faster than previously imaginable, will depend on how the technology performs in the clinic, but the barrier that once seemed inherent to the platform has now been shown to be one that can be engineered away.

Subject of Research: Cells

Article Title: Scientists overcome key barrier to self-amplifying vaccines

Article References: Scientists overcome key barrier to self-amplifying vaccines. (n.d.). Original publication

Image Credits: AI Generated

DOI: Not provided

Keywords: self-amplifying mRNA, saRNA vaccines, NoV B2 protein, double-stranded RNA, Queen Mary University of London, Nature Communications, Scientists, overcome, barrier, self-amplifying, vaccines, scientific research

The expectation that planets should orbit in the same direction as their host star is one of the most basic predictions of planet formation theory. Stars and their planets are born together from a single rotating cloud of gas and dust that collapses into a flattened, spinning disk. Because the star forms at the center of that disk and the planets condense within it, both should initially share the same sense of rotation, with planetary orbits aligned closely to the star’s equatorial plane. Deviations from this alignment, known as orbital obliquity, are therefore treated as evidence that something unusual happened after the planets formed, whether a violent gravitational encounter, a slow secular torque from a distant companion, or some other perturbation powerful enough to wrench the system out of its primordial configuration.

Measuring that alignment for a planet as small as GJ 3090 b is a formidable technical challenge. The team used the NIRPS near-infrared spectrograph, an instrument specifically designed to study planets around M dwarfs, the small, cool stars that account for the majority of stars in the Galaxy. By resolving the star’s spectrum at high resolution during planetary transits, the researchers could detect the subtle Doppler distortions produced as the planet blocks light from different parts of the rotating stellar surface, a technique known as the Rossiter-McLaughlin effect. Combining this signal with the planet’s known orbital parameters allowed them to reconstruct the full three-dimensional orientation of the orbit. The result was an obliquity of approximately 136 degrees, a value that places the planet firmly on a retrograde trajectory rather than merely on an inclined one.

Dr. Andrew Winter, a lead author from Queen Mary University of London, emphasized how extraordinary the configuration is. The planet, he noted, is not simply tilted relative to its star but is orbiting in the opposite direction altogether, a fact that immediately raises the question of how such an unusual orbit could have come about. Retrograde planets are among the most valuable laboratories in exoplanet science precisely because their orbits are so difficult to produce. In the standard picture, a sufficiently massive planet or a companion star can gravitationally disturb a planet’s orbit and tilt it dramatically over millions or billions of years, in some cases flipping it past the 90-degree threshold where it begins to move backwards relative to the star’s spin.

That standard picture gave the team a clear investigative strategy: look for the hidden companion. If a massive outer planet or a second star were lurking in the GJ 3090 system, its gravitational influence could plausibly have driven the observed misalignment through well-understood dynamical mechanisms such as the Kozai-Lidov effect or long-term secular perturbations. The researchers therefore searched their observational data for evidence of another massive object, examining radial velocity trends and other indicators that would betray the presence of an unseen companion. The search came up empty. Their observations found no evidence for a wide stellar companion, nor for a sufficiently massive outer planet that could readily account for the planet’s extreme orbital misalignment.

The absence of an obvious culprit makes the system particularly intriguing and has pushed the team toward explanations rooted in the system’s earliest history rather than in later violence. Yann Carteret, a PhD student at the University of Geneva who participated in the study, said the team looked for the kind of massive companion that could have forced the planet into such an extreme orbit but found no evidence for one, suggesting that researchers may need to think differently about how this system acquired its unusual architecture. One possibility the researchers propose is that the young star acquired a second, misaligned disk of gas and dust from its surrounding environment, perhaps through the accretion of material whose angular momentum was oriented differently from that of the original disk. Planets forming from this later material would inherit its orientation, producing a retrograde orbit without any catastrophic encounter ever taking place.

If that scenario is correct, the backwards orbit of GJ 3090 b would not be the scar of a later collision or perturbation but a fossil preserving the unusual conditions under which the planetary system formed. Assistant Professor Vincent Bourrier of the University of Geneva described the idea that a planetary system could be rebuilt from a second, differently oriented disk as particularly exciting, noting that it suggests the environment around a young star can play a far larger role in determining the architecture of its planets than researchers might have expected. Young stars are often born in dense clusters where gas flows, stellar flybys and infalling clouds are common, and any of these processes could in principle deliver misaligned material onto an existing disk, resetting the stage on which planets assemble.

Beyond its implications for formation theory, the study demonstrates the growing power of near-infrared observations for characterizing planets around M dwarfs. These small, cool stars emit most of their light at infrared wavelengths, making instruments like NIRPS far more effective than optical spectrographs for capturing the faint signals needed to measure orbital geometry. GJ 3090 b is now the smallest planet around an M dwarf for which a three-dimensional orbital obliquity has been measured, a milestone that opens an important new class of targets for comparative studies. Until recently, most obliquity measurements were restricted to hot Jupiters and other giant planets orbiting larger stars, leaving the demographic picture badly skewed toward systems that may not be representative of planetary systems as a whole.

The measurement also matters for what it says about the diversity of planetary architectures around the Galaxy’s most common stars. If small planets around M dwarfs can routinely end up on strongly misaligned or even retrograde orbits, then the tidy picture of coplanar, aligned systems that underpins much of exoplanet statistics may need substantial revision, particularly for the low-mass planets that current surveys are finding in abundance around nearby red dwarfs. The researchers caution that further observations will be needed to test the proposed second-disk formation scenario and to establish whether other planetary systems contain similarly extreme orbital configurations, work that will require expanding the still-tiny sample of small planets with measured obliquities.

For now, GJ 3090 b stands as a vivid reminder that planetary orbits are not always the quiet inheritances they are often assumed to be. The movements of planets with unusual orbits can act as fossils of planetary formation, preserving clues about the events and environments that shaped their systems billions of years ago. Whether the backwards Neptune owes its trajectory to a second misaligned disk, an as-yet-undetected companion, or some mechanism not yet imagined, its orbit is a message from the earliest epoch of the system’s history, and astronomers are only beginning to learn how to read it.

Subject of Research: Measurement of a retrograde orbital obliquity for the Neptune-sized exoplanet GJ 3090 b around an M dwarf star

Article Title: First ‘backwards’ planet discovered around a small star challenges ideas about how planets form

Article References: First ‘backwards’ planet discovered around a small star challenges ideas about how planets form. (n.d.). Original publication

Image Credits: AI Generated

DOI: Not provided

Keywords: exoplanet, retrograde orbit, GJ 3090 b, M dwarf, orbital obliquity, NIRPS, protoplanetary disk, planet formation, Astronomy & Astrophysics, spectroscopy, Queen Mary University of London, University of Geneva