Why Are Some Covid-19 Vaccines Working Better For Men Than Women? (Medicine)

MSU researcher is studying, raising awareness about the role of sex in the efficacy of vaccines that make use of nanomedicine

If there’s one take-home message for the general public about the coronavirus vaccines approved in the U.S., it’s that they are remarkably effective.

But Michigan State University’s Morteza Mahmoudi is raising awareness about an important subtlety: The vaccines developed by Moderna and Pfizer-BioNTech appear to work slightly better for men than for women.

Both vaccines use tiny orbs, or nanoparticles, to deliver their active ingredients to cells in our immune systems. For years, Mahmoudi has been studying how and why nanomedicines — therapies that use nanoparticles — can affect patients differently based on their sex and he believes this could be a factor with the vaccines.

The Johnson & Johnson vaccine has also drawn attention to sex differences because its rare blood-clotting side effect has affected predominantly women. The J&J vaccine, however, uses modified adenoviruses rather than nanoparticles to help teach our immune systems to fight off the coronavirus. That said, Mahmoudi has shown in earlier work that viruses can transfect the cells of men and women differently.

Now, he’s focusing on the nanomedicine component. He’s published three peer-reviewed papers calling attention to the role of sex in nanomedicine studies, both in general and as they relate to coronavirus vaccines.

MSU Assistant Professor Morteza Mahmoudi © MSU

“We need to monitor these sex differences and report them to the scientific community and the public,” said Mahmoudi, an assistant professor in the Department of Radiology and the Precision Health Program. “It can be very helpful in developing future strategies and as we prepare for future threats.”

To develop those future strategies, researchers must better understand what causes patients of different sexes to respond differently to nanomedicines, Mahmoudi said. To that end, Mahmoudi is advocating for systemic changes in how nanoparticles are used and studied in medicine with an article published May 20 in the journal Nature Communications.

In the article, he outlines four large challenges in researching the role of sex in nanomedicine performance along with strategies to mitigate them moving forward.

For example, researchers may not have sufficient resources to perform their studies in cells or other samples taken from men and women. Yet these researchers and others may still interpret their results as being equally applicable to all sexes. To prevent this from happening, Mahmoudi is calling for researchers to be more transparent and share sex-specific limitations of studies and conclusions.

“We need to be more careful about the science that gets out,” Mahmoudi said. “We’ve witnessed that there has not been a robust consideration of sex in nanomedicine, but we need to consider sex because it is important.”

Before the coronavirus pandemic, most of the research interest and funding in nanomedicine had been focused on its use in treating cancer. But nanomedicine’s performance in this realm has been lackluster. Less than 15% of nanomedicines that have entered clinical trials made it through the final phase and none have proven to be better than the standard of care, Mahmoudi said.

In addition, he said, when nanomedicines are robustly studied in women, it’s often because the therapies are being studied in diseases that mainly affect women, such as breast and ovarian cancers.

“Our analysis of the 41 completed clinical trial studies of therapeutic nanomedicine products revealed that 21 studies were stratified by sex because they concerned pathologies primarily found in females,” Mahmoudi said. “Of the remaining 20 studies involving 851 males and 430 females, none provided sex-stratified results or indications.”

Mahmoudi’s team detailed these findings and more in an article published online on May 4 in the journal Advanced Drug Delivery Reviews.

Despite their shortcomings in cancer therapies, nanoparticles have been greatly effective in helping provide protection against the novel coronavirus. Yet there is still evidence that the vaccines work differently for men and women.

“On the one hand, the vaccines have been really good news for nanomedicine,” Mahmoudi said. “But we didn’t solve the problems that we saw with them in cancer treatments.”

To be clear, the differences in vaccine efficacy are small, but they are measurable. In the case of the vaccine developed by the pharmaceutical company Moderna, clinical trials showed it was 95.4% effective at preventing COVID cases for men, compared with 93.1% for women. For the vaccine created by Pfizer and BioNTech, the numbers are 96.4% for men and 93.7% for women.

Both vaccines use nanoparticles based on lipids, which are fatty molecules that form tiny spheres in water, kind of like bubbles. The pharma companies then pack these tiny lipid-based particles with the vaccines’ active ingredients and essentially use the nanoparticles as delivery vehicles to ship the vaccines’ payloads to our immune cells.

Working with researchers at Sapienza University of Rome, Mahmoudi designed an experiment to test whether lipid-based nanoparticles could be a reason behind the difference in vaccine efficacy for men and women. The team published its results on May 13 in the journal Molecular Pharmacology.

The team added lipid-based nanoparticles with similarities to those used in the vaccines to blood samples taken from 18 patients, eight men and 10 women. The researchers then observed how well or how poorly immune cells within the blood adsorbed those nanoparticles. The team found a significant difference between men and women for one cell type called natural killer cells.

An electron micrograph has been colorized to show a spiny, tumbleweed-like natural killer cell in orange.
This colorized image shows a closeup of a microscopic natural killer cell. Credit: National Institutes of Allergy and Infectious Diseases, National Institutes of Health

“These cells are responsible for finding other infected cells — cells that are producing the virus — and they can kill them,” said Mahmoudi. “What we found is that natural killer cells respond to lipid-based nanoparticles in a sex-specific manner.”

Namely, natural killer cells from female donors took up fewer nanoparticles than natural killer cells from men. Based on this model system, then, it is plausible that the immune systems of men and women would respond differently to the vaccine.

But Mahmoudi and his colleagues also showed that the difference could be eliminated by first putting the nanoparticles in a donor’s plasma, the cell-free portion of their blood sample. Mahmoudi believes this because proteins in the plasma can bind to the lipid-based nanoparticles, giving the nanoparticle a biological coating or corona.

“I think of the corona as acting like a new passport for nanoparticles, it tells the cells how to respond to nanoparticles,” he said.

What this suggests, then, is that if there are differences in the vaccines’ performance based on a patient’s sex, doctors and researchers should be able to do something about it. But they’ll need more research and data to fully understand the cause of and remedies to these differences, Mahmoudi said. Thankfully, though, the data available to the community is growing every day.

“The clinical trials were performed with tens of thousands of patients. We know that the differences are there and that we need to monitor them,” he said. “Now we have millions of people getting the vaccines. That’s millions of data points. We need to go out there and get them.”

Reference: Hajipour, M.J., Aghaverdi, H., Serpooshan, V. et al. Sex as an important factor in nanomedicine. Nat Commun 12, 2984 (2021). https://doi.org/10.1038/s41467-021-23230-9

Provided by Michigan State University

Hubble Tracks Down Fast Radio Bursts to Galaxies’ Spiral Arms (Astronomy)

Astronomers using NASA’s Hubble Space Telescope have traced the locations of five brief, powerful radio blasts to the spiral arms of five distant galaxies. 

Called fast radio bursts (FRBs), these extraordinary events generate as much energy in a thousandth of a second as the Sun does in a year. Because these transient radio pulses disappear in much less than the blink of an eye, researchers have had a hard time tracking down where they come from, much less determining what kind of object or objects is causing them. Therefore, most of the time, astronomers don’t know exactly where to look. 

Astronomers using the Hubble Space Telescope have tracked down two brief, powerful radio bursts to the spiral arms of the two galaxies shown at top and bottom of this image.
Astronomers using the Hubble Space Telescope have tracked down two brief, powerful radio bursts to the spiral arms of the two galaxies shown above. The two images at left show the full Hubble snapshots of each galaxy. The two digitally enhanced images on the right reveal each galaxy’s spiral structure in more detail. The catalogue names of the bursts are FRB 190714 (top row), and FRB 180924 (bottom row). The galaxies are far from Earth, appearing as they looked billions of years ago. The dotted oval lines in each of the four images mark the location of the brilliant radio flares.Credits: SCIENCE: NASA, ESA, Alexandra Mannings (UC Santa Cruz), Wen-fai Fong (Northwestern) IMAGE PROCESSING: Alyssa Pagan (STScI)

Locating where these blasts are coming from, and in particular, what galaxies they originate from, is important in determining what kinds of astronomical events trigger such intense flashes of energy. The new Hubble survey of eight FRBs helps researchers narrow the list of possible FRB sources.

Flash in the Night

The first FRB was discovered in archived data recorded by the Parkes radio observatory on July 24, 2001. Since then astronomers have uncovered up to 1,000 FRBs, but they have only been able to associate roughly 15 of them to particular galaxies. 

“Our results are new and exciting. This is the first high-resolution view of a population of FRBs, and Hubble reveals that five of them are localized near or on a galaxy’s spiral arms,” said Alexandra Mannings of the University of California, Santa Cruz, the study’s lead author. “Most of the galaxies are massive, relatively young, and still forming stars. The imaging allows us to get a better idea of the overall host-galaxy properties, such as its mass and star-formation rate, as well as probe what’s happening right at the FRB position because Hubble has such great resolution.”

In the Hubble study, astronomers not only pinned all of them to host galaxies, but they also identified the kinds of locations they originated from. Hubble observed one of the FRB locations in 2017 and the other seven in 2019 and 2020.

“We don’t know what causes FRBs, so it’s really important to use context when we have it,” said team member Wen-fai Fong of Northwestern University in Evanston, Illinois. “This technique has worked very well for identifying the progenitors of other types of transients, such as supernovae and gamma-ray bursts. Hubble played a big role in those studies, too.”

The galaxies in the Hubble study existed billions of years ago. Astronomers, therefore, are seeing the galaxies as they appeared when the universe was about half its current age. 

Many of them are as massive as our Milky Way. The observations were made in ultraviolet and near-infrared light with Hubble’s Wide Field Camera 3.

Ultraviolet light traces the glow of young stars strung along a spiral galaxy’s winding arms. The researchers used the near-infrared images to calculate the galaxies’ mass and find where older populations of stars reside.

Hunting for the neighborhoods of enigmatic, fast radio bursts (FRBs), astronomers using the Hubble Space Telescope tracked four of them to the spiral arms of the four distant galaxies shown in the image.
Hunting for the neighborhoods of enigmatic fast radio bursts (FRBs), astronomers using the Hubble Space Telescope tracked four of them to the spiral arms of the four distant galaxies shown in the image. The bursts are catalogued as FRB 190714 (top left), FRB 191001 (top right), FRB 180924 (bottom left), and FRB 190608 (bottom right). Because these radio pulses disappear in much less than the blink of an eye, researchers have had a hard time tracking down where they come from. With the help of Hubble’s sharp vision, astronomers pinpointed their locations (denoted by the dotted oval lines) to the galaxies’ spiral arms.Credits: SCIENCE: NASA, ESA, Alexandra Mannings (UC Santa Cruz), Wen-fai Fong (Northwestern) IMAGE PROCESSING: Alyssa Pagan (STScI)

Location, Location, Location

The images display a diversity of spiral-arm structure, from tightly wound to more diffuse, revealing how the stars are distributed along these prominent features. A galaxy’s spiral arms trace the distribution of young, massive stars. However, the Hubble images reveal that the FRBs found near the spiral arms do not come from the very brightest regions, which blaze with the light from hefty stars. The images help support a picture that the FRBs likely do not originate from the youngest, most massive stars.

These clues helped the researchers rule out some of the possible triggers of types of these brilliant flares, including the explosive deaths of the youngest, most massive stars, which generate gamma-ray bursts and some types of supernovae. Another unlikely source is the merger of neutron stars, the crushed cores of stars that end their lives in supernova explosions. These mergers take billions of years to occur and are usually found far from the spiral arms of older galaxies that are no longer forming stars.

Magnetic Monsters

The team’s Hubble results, however, are consistent with the leading model that FRBs originate from young magnetar outbursts. Magnetars are a type of neutron star with powerful magnetic fields. They’re called the strongest magnets in the universe, possessing a magnetic field that is 10 trillion times more powerful than a refrigerator door magnet. Astronomers last year linked observations of an FRB spotted in our Milky Way galaxy with a region where a known magnetar resides. 

Video: Fast radio bursts, or FRBs, are extraordinary events that generate as much energy in a thousandth of a second as the Sun does in an entire year! Astronomers using NASA’s Hubble Space Telescope have traced the locations of five brief, powerful FRBs, which are near or on their host galaxies’ spiral arms. The research helped rule out some of the possible stellar objects originally thought to cause these brilliant flares.Credits: NASA’s Goddard Space Flight Center

“Owing to their strong magnetic fields, magnetars are quite unpredictable,” Fong explained. “In this case, the FRBs are thought to come from flares from a young magnetar. Massive stars go through stellar evolution and becomes neutron stars, some of which can be strongly magnetized, leading to flares and magnetic processes on their surfaces, which can emit radio light. Our study fits in with that picture and rules out either very young or very old progenitors for FRBs.”

The observations also helped the researchers strengthen the association of FRBs with massive, star-forming galaxies. Previous ground-based observations of some possible FRB host galaxies did not as clearly detect underlying structure, such as spiral arms, in many of them. Astronomers, therefore, could not rule out the possibility that FRBs originate from a dwarf galaxy hiding underneath a massive one. In the new Hubble study, careful image processing and analysis of the images allowed researchers to rule out underlying dwarf galaxies, according to co-author Sunil Simha of the University of California, Santa Cruz.

Although the Hubble results are exciting, the researchers say they need more observations to develop a more definitive picture of these enigmatic flashes and better pinpoint their source. “This is such a new and exciting field,” Fong said. “Finding these localized events is a major piece to the puzzle, and a very unique puzzle piece compared to what’s been done before. This is a unique contribution of Hubble.”The team’s results will appear in an upcoming issue of The Astrophysical Journal.

The Hubble Space Telescope is a project of international cooperation between NASA and ESA (European Space Agency). NASA’s Goddard Space Flight Center in Greenbelt, Maryland, manages the telescope. The Space Telescope Science Institute (STScI) in Baltimore, Maryland, conducts Hubble science operations. STScI is operated for NASA by the Association of Universities for Research in Astronomy in Washington, D.C.

Provided by NASA

Rare 400-Year Comets Can Cause Meteor Showers On Earth (Planetary Science)

Comets that circle the Sun in very elongated orbits spread their debris so thin along their orbit or eject it out of the solar system altogether that their meteor showers are hard to detect. From a new meteor shower survey published in the journal Icarus, researchers now report that they can detect showers from the debris in the path of comets that pass close to Earth orbit and are known to return as infrequent as once every 4,000 years.

“This creates a situational awareness for potentially hazardous comets that were last near-Earth orbit as far back as 2,000 BC,” said meteor astronomer and lead author Peter Jenniskens of the SETI Institute.

Jenniskens is the lead of the Cameras for Allsky Meteor Surveillance (CAMS) project, which observes and triangulates the visible meteors in the night sky using low- light video security cameras to measure their trajectory and orbit. There are CAMS networks now in nine countries, led by co-authors on the paper.

In recent years, new networks in Australia, Chile and Namibia significantly increased the number of triangulated meteors. The addition of these networks resulted in a better and more complete picture of the meteor showers in the night sky.

“Until recently, we only knew five long-period comets to be parent bodies to one of our meteor showers,” said Jenniskens, “but now we identified nine more, and perhaps as many as 15.”

Comets comprise only a small fraction of all impactors on Earth, but researchers believe they caused some of the biggest impact events over Earth’s history because they can be big and the fact that their orbits are such that they can impact at high speed.

“In the future, with more observations, we may be able to detect fainter showers and trace the orbit of parent comets on even longer orbits,” said Jenniskens.

Every night, the CAMS network determines the direction from which comet debris is entering Earth’s atmosphere. Maps are created on an interactive celestial sphere (posted at http://cams.seti.org/FDL/) that shows the meteor showers as colored blobs. Clicking on those blobs shows the measured orbits in the solar system.

April 22, 2021, Lyrid meteor shower radiants in CAMS data (yellow dots) from long-period comet Thatcher. Photo: P. Jenniskens / SETI Institute.

“These are the shooting stars you see with the naked eye,” said Jenniskens. “By tracing their approach direction, these maps show the sky and the universe around us in a very different light.”

An analysis of the data found that long-period comet meteor showers can last for many days.

“This was a surprise to me,” says Jenniskens. “It probably means that these comets returned to the solar system many times in the past, while their orbits gradually changed over time.”

Data also revealed that the most dispersed meteor showers show the highest fraction of small meteoroids.

“The most dispersed showers are probably the oldest ones,” says Jenniskens. “So, this could mean that the larger meteoroids fall apart into smaller meteoroids over time.”

Read full paper here: https://sciencedirect.com/science/article/pii/S0019103521001500/

CAMS network website: http://cams.seti.org/FDL/

Featured image: The meteoroid stream of long-period comet Thatcher from CAMS data. Outer blue ellipse is the orbit of Neptune. Photo: P. Jenniskens / SETI Institute

Reference: Peter Jenniskens, Dante S. Lauretta, Martin C. Towner, Steve Heathcote, Emmanuel Jehin, Toni Hanke, Tim Cooper, Jack W. Baggaley, J. Andreas Howell, Carl Johannink, Martin Breukers, Mohammad Odeh, Nicholas Moskovitz, Luke Juneau, Tim Beck, Marcelo De Cicco, Dave Samuels, Steve Rau, Jim Albers, Peter S. Gural, Meteor showers from known long-period comets, Icarus, Volume 365, 2021, 114469, ISSN 0019-1035, https://doi.org/10.1016/j.icarus.2021.114469. (https://www.sciencedirect.com/science/article/pii/S0019103521001500)

Provided by Seti Institute

Clearing the Air: A Reduction-Based Solution to Nitrogen Pollution with a Novel Catalyst (Chemistry)

A new iron catalyst helps preferentially reduce nitric oxide to hydroxylamine, opening doors to pollution control and clean energy.

Our reliance on fossil fuels as a primary energy source has pushed air pollution to an all-time high, resulting in several environmental and health concerns. Among the major pollutants, nitrogen oxide (NOx) accumulation can cause severe respiratory diseases and imbalance in the Earth’s nitrogen cycle. Reducing NOx accumulation is, therefore, an issue of utmost importance.

Recently, the conversion of NOx into harmless or even useful nitrogen products has emerged as a promising strategy. Particularly appealing to scientists is the reduction of NOx to hydroxylamine (NH2OH), which can be utilized as a renewable source of energy.

The “make-or-break” step that determines the formation of hydroxylamine is the catalytic electrochemical reduction of nitric oxide (NO), which can either yield hydroxylamine or nitrous oxide (N2O), depending on the electrolyte pH and electrode potential. Studies show that for hydroxylamine formation to dominate over N2O formation, very acidic electrolytes with a pH less than 0 are required. However, such a harshly acidic environment rapidly degrades the catalyst, limiting the reaction. “The development of a new catalyst with high activity, selectivity, and stability is the next challenge,” says Prof. Chang Hyuck Choi from the Gwangju Institute of Science and Technology (GIST) in Korea where he works on the catalysis of electrochemical reactions.

In a recent study published in Nature Communications, Prof. Choi and his colleagues from Korea and France investigated NO reduction in the presence of a new iron-nitrogen-doped carbon (Fe-N-C) catalyst made of isolated FeNxCy moieties bonded to a carbonaceous substrate. The catalyst was chosen for its high selectivity for the NH2OH pathway as well as its resistance to extremely acidic conditions.

The team performed in operando (i.e., during the reaction) spectroscopy and electrochemical analysis of the catalyst to determine its catalytic site and the pH dependence of NH2OH production.

They identified the active site of the catalyst as the ferrous moieties bonded to the carbon substrate where the rate of NH2OH formation showed a peculiar increase with decreasing pH. The team attributed this peculiarity to an uncertain oxidation state of NO. Finally, they achieved efficient (71%) NH2OH production in a prototypical NO-H2 fuel cell, establishing the catalyst’s practical utility. Moreover, they found that the catalyst exhibited long-term stability, showing no signs of deactivation even after operating for over 50 hours!

The approach not only reduces harmful air pollutants, but also provides a useful byproduct that may find use in ushering in a renewable energy society. “Apart from the applications of hydroxylamine in the nylon industry, it can also be used as an alternative hydrogen carrier. Thus, the new catalyst will not only help reduce the amount of NOx pollutants in our atmosphere but also lead us to a renewable energy future,” Prof. Choi explains.

We can breathe easy knowing that the team’s findings take us a few steps closer to a pollution-free renewable energy society.

Featured image: A new iron catalyst helps preferentially reduce nitric oxide to hydroxylamine, opening doors to pollution control and clean energy. © GIST


  • Title of original paper: Selective electrochemical reduction of nitric oxide to hydroxylamine by atomically dispersed iron catalyst
  • JournalNature Communications
  • DOIhttps://doi.org/10.1038/s41467-021-22147-7

Provided by Gwangju Institute of Science and Technology (GIST)

Origins of Life Researchers Develop A New Ecological Biosignature (Astronomy / Biology)

When scientists hunt for life, they often look for biosignatures, chemicals or phenomena that indicate the existence of present or past life. Yet it isn’t necessarily the case that the signs of life on Earth are signs of life in other planetary environments. How do we find life in systems that do not resemble ours?

In groundbreaking new work, a team* led by Santa Fe Institute Professor Chris Kempes has developed a new ecological biosignature that could help scientists detect life in vastly different environments. Their work appears as part of a special issue of the Bulletin of Mathematical Biology collected in honor of renowned mathematical biologist James D. Murray.

The new research takes its starting point from the idea that stoichiometry, or chemical ratios, can serve as biosignatures. Since “living systems display strikingly consistent ratios in their chemical make-up,” Kempes explains, “we can use stoichiometry to help us detect life.” Yet, as SFI Science Board member and contributor, Simon Levin, explains, “the particular elemental ratios we see on Earth are the result of the particular conditions here, and a particular set of macromolecules like proteins and ribosomes, which have their own stoichiometry.” How can these elemental ratios be generalized beyond the life that we observe on our own planet?

The group solved this problem by building on two lawlike patterns, two scaling laws, that are entangled in elemental ratios we have observed on Earth. The first of these is that in individual cells, stoichiometry varies with cell size. In bacteria, for example, as cell size increases, protein concentrations decrease, and RNA concentrations increase. The second is that the abundance of cells in a given environment follows a power-law distribution. The third, which follows from integrating the first and second into a simple ecological model, is that the elemental abundance of particles to the elemental abundance in the environmental fluid is a function of particle size.

While the first of these (that elemental ratios shift with particle size) makes for a chemical biosignature, it is the third finding that makes for the new ecological biosignature. If we think of biosignatures not simply in terms of single chemicals or particles, and instead take account of the fluids in which particles appear, we see that the chemical abundances of living systems manifest themselves in mathematical ratios between the particle and environment. These general mathematical patterns may show up in coupled systems that differ significantly from Earth.

Ultimately, the theoretical framework is designed for application in future planetary missions. “If we go to an ocean world and look at particles in context with their fluid, we can start to ask whether these particles are exhibiting a power-law that tells us that there is an intentional process, like life, making them,” explains Heather Graham, Deputy Principal Investigator at NASA’s Lab for Agnostic Biosignatures, of which she and Kempes are a part. To take this applied step, however, we need technology to size-sort particles, which, at the moment, we don’t have for spaceflight. Yet the theory is ready, and when the technology lands on Earth, we can send it to icy oceans beyond our solar system with a promising new biosignature in hand.  

Read the paper,  “Generalized Stoichiometry and Biogeochemistry for Astrobiological Applications,” in the Bulletin of Mathematical Biology (May 18, 2021)

*Christopher Kempes (Santa Fe Institute), Michael Follows (MIT), Hillary Smith (Pennsylvania State University), Heather Graham (NASA Goddard Spaceflight Center), Christopher House (Pennsylvania State University), and Simon Levin (Princeton University, Santa Fe Institute) are co-authors on the paper.

Featured image: Artist’s conception of where life might be found on a distant planet. (Illustration: NASA)

Provided by Santa Fe Institute

Out Of Thick Air: Transforming CO2 Into Light-emitting Carbon (Engineering)

Breakthrough by uOttawa researchers sees creation of light-emitting solid carbon from CO2 gas

A team of researchers at the University of Ottawa has found a way to use visible light to transform carbon dioxide gas, or CO2, into solid carbon forms that emit light. This development creates a new, low-energy COreduction pathway to solid carbon that will have implications across many fields.

We talked to lead author Dr. Jaspreet Walia, Post-Doctoral Fellow in the School of Electrical Engineering and Computer Science at the University of Ottawa, and research lead Dr. Pierre Berini, uOttawa Distinguished Professor and University Research Chair in Surface Plasmon Photonics, to learn more. 

Solid carbon on a nanostructured silver surface illuminated with green light
Credit: University of Ottawa

Please tell us about your team’s discovery.

Pierre Berini: “We have reduced carbon dioxide, a greenhouse gas, to solid carbon on a nanostructured silver surface illuminated with green light, without the need for any other reagents. Energetic electrons excited on the silver surface by green light transfer to carbon dioxide molecules, initiating dissociation. The carbon deposits were also found to emit intense yellow light in a process known as photoluminescence.”

How did you come to these conclusions?

Jaspreet Walia: “We used a technique known as Raman Scattering to probe the reaction in real time to determine which products, if any, were forming. To our surprise, we consistently observed signatures of carbon forming on the surface, as well as bright and visible yellow light emanating from the sample.”

This image shows light emission, a process known as photoluminescence, form solid carbon which has formed on a silver nanostructure, illuminated by green light
This image shows light emission, a process known as photoluminescence, form solid carbon which has formed on a silver nanostructure, illuminated by green light. Credit: University of Ottawa, OSA Optica

Why is it important?

Pierre Berini: “Recently, there has been considerable global research effort devoted to developing technologies that can transform CO2 using visible light. Our work not only demonstrates that this is possible, but also that light emitting solid carbon can be formed.”

What are the applications of this discovery in our lives?

Jaspreet Walia: “This fixed pathway for reagent-less CO2 reduction to light emitting solid carbon, driven by visible light, will be of interest to researchers involved in the development of solar driven chemical transformations, industrial scale catalytic processes, and light-emitting metasurfaces.”

“More specifically, with respect to the creation of carbon directly from CO2 gas, our findings will have an impact on research involving plasmon assisted reactions and I would expect the emergence of applications in the oil and gas industries, where catalytic transformations involving carbon-based compounds is a key focus area.”

“Next-generation reactions involving CO2 and light could also lead to other useful outcomes, such as the potential for artificial photosynthesis. Our findings could be used for light control and manipulation at the nanoscale, or to possibility realize flat light sources due to the light-emitting aspect of our discovery. The nanostructured carbon itself could also be used in catalysis.”

“Finally, the wavelength (color) of the light emitted from carbon dots on a silver surface could be very sensitive to the local environment, making it an attractive sensing platform for pollutants, for example.”

Is there anything you would like to add?

Pierre Berini: “We have learned how to form solid carbon deposits that emit light “out of thick air”, in a breakthrough enabled by light-assisted transformation of CO2 gas driven by energetic electrons. The project was entirely driven by curiosity, with no set expectations on outcomes, and benefitted from close collaboration with graduate students Sabaa Rashid and Graham Killaire, as well as Professors Fabio Variola and Arnaud Weck.”

The research took place at the uOttawa Centre for Research in Photonics, from January 2020 to present. The paper “Reconfigurable carbon quantum emitters from CO2 gas reduced via surface plasmons” is published in the journal Optica as a memorandum.

Provided by University of Ottawa

Duke-Led Team Identifies New Coronavirus Threat to Humans (Biology)

Researchers have discovered a new coronavirus, found in a child with pneumonia in Malaysia in 2018 that appeared to have jumped from dog to human. 

If confirmed as a pathogen, the novel canine-like coronavirus could represent the eighth unique coronavirus known to cause disease in humans. The discovery suggests coronaviruses are being transmitted from animals to humans more commonly than was previously thought.

“How common this virus is, and whether it can be transmitted efficiently from dogs to humans or between humans, nobody knows,” said Gregory Gray, M.D., a professor of medicine, global health and environmental health at the Duke University. 

“What’s more important is that these coronaviruses are likely spilling over to humans from animals much more frequently than we know,” said Gray, who led the research that appears in the journal Clinical Infectious Diseases. “We are missing them because most hospital diagnostic tests only pick up known human coronaviruses.”

Working with visiting scholar Leshan Xiu, a Ph.D. student, Gray was on a team that in 2020 developed a molecular diagnostic tool to detect most every coronaviruses from the Coronaviridae family that includes SARS-CoV-2, which causes COVID-19.

The team used that tool to examine 301 archived pneumonia cases and picked up signals for canine coronaviruses from eight people hospitalized with pneumonia in Sarawak, a state in East Malaysia. 

Researchers at Ohio State, led by Anastasia N. Vlasova, grew a virus from one of the clinical specimens, and through a painstaking process of genome reconstruction, were able to identify it as a novel canine coronavirus.

“There are probably multiple canine coronaviruses circulating and spilling over into humans that we don’t know about,” Gray said. Sarawak could be a rich place to detect them, he said, since it’s an equatorial area with rich biodiversity.

“Many of those spillovers are dead ends, they don’t ever leave that first human host,” Gray said. “But if we really want to mitigate the threat, we need better surveillance where humans and animals intersect, and among people who are sick enough to get hospitalized for novel viruses.”

Gray said diagnostic tools like the one developed to find this virus have the potential to identify other viruses new to humans before they can cause a pandemic. 

“These pathogens don’t just cause a pandemic overnight,” Gray said. “It takes many years for them to adapt to the human immune system and cause infection, and then to become efficient in human-to-human transmission. We need to look for these pathogens and detect them early.”

In addition to Gray and Vlasova, researchers included Annika Diaz, Teck-Hock Toh, Jeffrey Soon-Yit Lee and Linda J. Saif.

This work was supported by the U.S. Naval Medical Research Center-Asia, Vysnova Partners, Duke University’s Global Health Institute and The Ohio State University.

Provided by Duke Health

Newly Identified Antibody Can Be Targeted by HIV Vaccines (Medicine)

A newly identified group of antibodies that binds to a coating of sugars on the outer shell of HIV is effective in neutralizing the virus and points to a novel vaccine approach that could also potentially be used against SARS-CoV-2 and fungal pathogens, researchers at the Duke Human Vaccine Institute report.

In a study appearing online May 20 in the journal Cell, the researchers describe an immune cell found in both monkeys and humans that produces a unique type of anti-glycan antibody. This newly described antibody has the ability to attach to the outer layer of HIV at a patch of glycans — the chain-like structures of sugars that are on the surfaces of cells, including the outer shells of viruses. 

“This represents a new form of host defense,” said senior author Barton Haynes, M.D., director of the Duke Human Vaccine Institute (DHVI). “These new antibodies have a special shape and could be effective against a variety of pathogens. It’s very exciting.”

Haynes and colleagues — including lead author Wilton Williams, Ph.D., director of the Viral Genetics Analysis Core at DHVI and co-author Priyamvada Acharya, Ph.D., director of the Division of Structural Biology at DHVI — found the antibody during a series of studies exploring whether there might be an immune response targeted to glycans that cover the outer surface of HIV. 

More than 50% of the virus’s outer layer is comprised of glycans. Haynes said it has long been a tempting approach to unleash anti-glycan antibodies to break down these sugar structures, triggering immune B-cell lymphocytes to produce antibodies to neutralize HIV.

“Of course, it’s not that simple,” Haynes said.

Instead, HIV is cloaked in sugars that look like the host’s glycans, creating a shield that makes the virus appear to be part of the host rather than a deadly pathogen. 

But the newly identified group of anti-glycan antibodies — referred by the Duke team as Fab-dimerized glycan-reactive (FDG) antibodies — had gone undiscovered as a potential option. 

To date, there was only one report of a similar anti-glycan HIV antibody with an unusual structure that was found 24 years ago (termed 2G12). The Duke team has now isolated several FDG antibodies and found that they display a rare, never-before-seen structure that resembled 2G12. This structure enables the antibody to lock tightly onto a specific, dense patch of sugars on HIV, but not on other cellular surfaces swathed in host glycans.

“The structural and functional characteristics of these antibodies can be used to design vaccines that target this glycan patch on HIV, eliciting a B-cell response that neutralizes the virus,” Williams said.

“These antibodies are actually much more common in blood cells than other neutralizing antibodies that target specific regions of the HIV outer layer,” Williams said. “That’s an exciting finding, because it overcomes one of the biggest complexities associated with other types of broadly neutralizing antibodies.”

Williams said the FDG antibodies also bind to a pathogenic yeast called Candida albicans, and to viruses, including SARS-CoV-2, which causes COVID-19. Additional studies will explore ways of harnessing the antibody and deploying it against these pathogens. 

In addition to Haynes, Williams and Acharya, study authors include R. Ryan Meyerhoff, R.J. Edwards, Hui Li, Kartik Manne, Nathan I. Nicely, Rory Henderson, Ye Zhou, Katarzyna Janowska, Katayoun Mansouri, Sophie Gobeil, Tyler Evangelous, Bhavna Hora, Madison Berry, A. Yousef Abuahmad, Jordan Sprenz, Margaret Deyton, Victoria Stalls, Megan Kopp, Allen L. Hsu, Mario J. Borgnia, Guillaume Stewart-Jones, Matthew S. Lee, Naomi Bronkema, M. Anthony Moody, Kevin Wiehe, Todd Bradley, S. Munir Alam, Robert J. Parks, Andrew Foulger, Thomas Oguin, Gregory D. Sempowski, Mattia Bonsignori, Celia C. LaBranche, David C. Montefiori, Michael Seaman, Sampa Santra, John Perfect, Joseph R. Francica, Geoffrey M. Lynn, Baptiste Aussedat, William E. Walkowicz, Richard Laga, Garnett Kelsoe, Kevin O. Saunders, Daniela Fera, Peter D. Kwong, Robert A. Seder, Alberto Bartesaghi and George M. Shaw.

The study received funding support from the Consortia for HIV/AIDS Vaccine Development, the National Institutes of Health, the National Institute of Allergy and Infectious Diseases, Division of AIDS (UM1-AI44371).

Reference: Wilton B. Williams, R. Ryan Meyerhoff et al., “Fab-dimerized glycan-reactive antibodies are a structural category of natural antibodies”, Cell, 2021. DOI: https://doi.org/10.1016/j.cell.2021.04.042

Provided by Duke Health news

The Viruses in Our Genes: When Activated, They Damage Brain Development (Medicine)

Since our ancestors infected themselves with retroviruses millions of years ago, we have carried elements of these viruses in our genes – known as human endogenous retroviruses, or HERVs for short. These viral elements have lost their ability to replicate and infect during evolution, but are an integral part of our genetic makeup. In fact, humans possess five times more HERVs in non-coding parts than coding genes. So far, strong focus has been devoted to the correlation of HERVs and the onset or progression of diseases. This is why HERV expression has been studied in samples of pathological origin. Although important, these studies do not provide conclusions about whether HERVs are the cause or the consequence of such disease.

Today, new technologies enable scientists to receive a deeper insight into the mechanisms of HERVs and their function. Together with her colleagues, virologist Michelle Vincendeau* has now succeeded for the first time in demonstrating the negative effects of HERV activation on human brain development.

HERV activation impairs brain development

Using CRISPR technology, the researchers activated a specific group of human endogenous retroviruses** in human embryonic stem cells and generated nerve cells (neurons). These viral elements in turn activated specific genes, including classical developmental factors, involved in brain development. As a result, cortical neurons, meaning the nerve cells in our cerebral cortex, lost their function entirely. They developed very differently from healthy neurons in this brain region – with much a shorter axon (nerve cell extension) that were much less branched. Thus, activation of one specific HERV group impairs cortical neuron development and ultimately brain development.

Clinical relevance

Since neurodegenerative diseases are often associated with the activation of several HERV groups, the negative impact of HERV activation on cortical neuron development is an essential finding. It is already known that environmental factors such as viruses, bacteria, and UV light can activate distinct HERVs, thereby potentially contributing to disease onset. This knowledge, in turn, makes HERVs even more interesting for clinical application. Switching off distinct viral elements could open up a new field of research for the treatment of patients with neurodegenerative diseases. In a next step, the group at Helmholtz Zentrum München will study the impact of HERV deactivation in neurons in the context of disease.

New paths for basic research

In addition, the research findings provide important indications that epigenetic mechanisms keep viral elements under control in healthy brain development. Michelle Vincendeau even suspects a functional role for the controlled HERVs in normal brain development. “We have carried these elements for about 40 to 70 million years. We assume that their presence is relevant to our natural processes, otherwise we would not have retained them for so long during evolution,” Vincendeau says. Further basic research in this direction might reveal new functional roles for HERVs.

* Michelle Vincendeau leads the research group for Human Endogenous Retroviruses at the Institute of Viorology at Helmholtz Zentrum München. Part of the data from the current study was generated in the context of her previous work at the Memorial Sloan Kettering Cancer Center in New York. For this paper, she also collaborated with researchers at the Technical University of Munich and the University of Saarland.

** HERV-K(HML-2)

Featured image: Neurons on the right have lost their function and show a different phenotype. © Helmholtz Zentrum München / Michelle Vincendeau

Original publication

Nair et al., 2021: Activation of HERV-K(HML-2) disrupts cortical patterning and neuronal differentiation by increasing NTRK3. Cell Stem Cell, DOI: 10.1016/j.stem.2021.04.009

Provided by Helmholtz-Zentrum Munchen