Culture

Washington, DC - January 22, 2020 - Candida auris is capable of forming high burden biofilms, which may help explain why this fungal pathogen is spreading in hospitals worldwide, according to a study published this week in mSphere, an open-access journal of the American Society for Microbiology. The research also establishes a new model to investigate the spread of this emerging fungal pathogen that causes invasive infections and is an emerging problem in hospitals worldwide.

"With these findings, we are able to have new tools to examine how Candida auris forms biofilms and spreads in this setting. Understanding more about this process could help us develop new strategies to prevent biofilm formation," said Jeniel Nett, MD, PhD, the study's principal investigator and assistant professor in the Departments of Medicine and Medical Microbiology & Immunology at the University of Wisconsin School of Medicine and Public Health. "Our tools can be used to determine how the biofilms are formed, which may lead to new strategies to prevent the transmission of or pharmaceutically target Candida auris."

Unlike many other Candida species, Candida auris spreads rapidly among patients and is efficient at colonizing skin. Because many of the patients infected with Candida auris have indwelling medical devices such as vascular catheters and endotracheal tubes, the researchers hypothesized that biofilms may be forming on these devices and on skin, facilitating transmission of Candida auris. "Candida species, similar to other fungal species and bacteria, can form communities that are adherent to a substrate, either on an artificial device or other surface," said Dr. Nett. "These biofilms communities are multilayered, and they often resist medical treatment, including antifungals, and host responses."

In the new study, Dr. Nett and colleagues developed a synthetic sweat media to represent skin conditions and using this model, they evaluated the growth of Candida auris and Candida albicans, one of the most common Candida species. They also examined the growth of these Candida species using a pig skin model to represent human skin conditions.

The researchers found that Candida auris exhibited a heightened capacity to both grow in the skin niche condition and to colonize pig skin and that Candida auris grew and colonized pig skin by forming multilayer biofilms. "Candida auris can grow approximately tenfold greater as a biofilm in this setting when compared to Candida albicans, one of the more common Candida species that does not seem to spread in hospital settings in this way," said Dr. Nett. "We think that this mode of growth is how Candida auris propagates in healthcare settings. Candida auris appears to colonize skin exceptionally well, growing particularly well in skin niche conditions."

The researchers said the formation of the biofilms is one of the reasons why Candida auris is difficult to clean in hospital settings. "These biofilms are likely on a lot of medical equipment used in healthcare settings," said Dr. Nett.

The researchers said their next steps are to further develop their model and examine Candida auris growth to determine some of the triggers for how Candida forms biofilms. "I was surprised that Candida auris formed such a condensed biofilm in this skin setting, as other species did not," said Dr. Nett. "We hypothesized that Candida auris may have a capacity to replicate in this environment, but we didn't expect it would be tenfold greater than the other Candida species."

It's a leading research strategy for eliminating HIV from the body: "shock and kill." The idea is to activate the dormant virus from within the immune cells where it hides, then eliminate it. One obstacle has been finding a safe way to wake up the virus.

In two complementary Nature papers, researchers now report that they have come closer to that goal. The papers are from researchers at the Yerkes National Primate Research Center of Emory University and the University of North Carolina at Chapel Hill, funded by the National Institutes of Health.

The papers rely on studies involving two animal models of HIV infection. Each study took a different approach. But both yielded promising results, disrupting viral latency at levels not seen before.

That means that the virus came out of its hiding places, even in the presence of antiretroviral drugs that had stopped it from replicating for months.

The findings do not represent a cure and follow-up studies in animals, as well as clinical studies in humans, are needed and planned. But the results represent an advance because they could potentially be combined with other approaches directed against the virus, the scientists say.

"If our goal is to cure HIV/AIDS, then we have to disrupt viral latency," says Guido Silvestri, MD, senior author of one of the Nature papers. "What we're doing now is a new combination approach that provides unprecedented levels of virus reactivation."

Silvestri is interim chair of pathology and laboratory medicine at Emory University School of Medicine, chief of microbiology and immunology at Yerkes National Primate Research Center, and a Georgia Eminent Research Scholar.

Past results of latency reversal experiments were not as sustained and extensive, says co-senior author J. Victor Garcia, PhD, director of the International Center for the Advancement of Translational Science and professor at the University of North Carolina School of Medicine.

"Previously, no one had successfully demonstrated systemic HIV induction in humans or an animal model with human cells, and then replicated this success in a completely different species infected with a different virus," Garcia says.

Ann Chahroudi, MD, PhD, co-senior author on both papers, says the studies described in the two papers take different approaches. She is associate professor of pediatrics and director of the Center for Childhood Infections & Vaccines at Emory and Children's Healthcare of Atlanta.

Both approaches were tested at Yerkes in monkeys infected with SIV, a close relative of HIV, and treated with antiretroviral drugs. At UNC, tests were also conducted in mice transplanted with human immune cells.

One paper describes a drug called AZD5582, which activates an intracellular pathway that leads to HIV and SIV reactivation. AZD5582 appears to be safe and relatively non-toxic in non-human primates. In 12 monkeys treated with the drug, just one experienced a temporary fever and loss of appetite. With the aim of beginning clinical trials, researchers at UNC and Qura Therapeutics -- a partnership between UNC and ViiV Healthcare -- are investigating compounds related to AZD5582.

"AZD5582 was remarkable in its ability to reactivate latent SIV from resting CD4+ T cells, and to induce continued virus production in the blood when monkeys were still receiving daily antiretroviral therapy," says Chahroudi.

In the study described in the second paper, researchers stimulated the cells that are the main viral hosts (CD4+ T cells) while also depleting another kind of immune cell (CD8+ T cells), which normally keeps the virus in check.

The combination of immune interventions was especially potent; both the stimulation and depletion components were necessary to see SIV re-emerge, Silvestri says. His lab had previously observed a similar but smaller effect with CD8 depletion alone. That means that CD8 T cells must have a role in keeping the virus inactive, which needs to be understood better, he says.

"The old paradigm is that you need CD8 cells to clear other infected cells," Silvestri says. "We're showing that CD8 cells are also involved in repressing latency reversal."

The main obstacle to a cure for HIV infection is the reservoir: immune cells that harbor the inactive virus when someone is being treated with antiretroviral drugs. Neither intervention - drug or immune stimulation/depletions - reduced the size of the reservoir, because once the animals were taken off antiretroviral drugs, viral levels did rebound. The scientists think the initial viral reactivation needs to be combined with other modes of treatment, such as antibodies directed against the virus itself.

"The exciting thing about these papers being published together are the concordance of the results in two animal models with both approaches, and the opening up of new avenues for research towards the goal of an HIV cure," says Chahroudi.

When Marie Antoinette was captured during the French Revolution, her hair reportedly turned white overnight. In more recent history, John McCain experienced severe injuries as a prisoner of war during the Vietnam War -- and lost color in his hair.

For a long time, anecdotes have connected stressful experiences with the phenomenon of hair graying. Now, for the first time, Harvard University scientists have discovered exactly how the process plays out: stress activates nerves that are part of the fight-or-flight response, which in turn cause permanent damage to pigment-regenerating stem cells in hair follicles.

The study, published in Nature, advances scientists' knowledge of how stress can impact the body.

"Everyone has an anecdote to share about how stress affects their body, particularly in their skin and hair -- the only tissues we can see from the outside," said senior author Ya-Chieh Hsu, the Alvin and Esta Star Associate Professor of Stem Cell and Regenerative Biology at Harvard. "We wanted to understand if this connection is true, and if so, how stress leads to changes in diverse tissues. Hair pigmentation is such an accessible and tractable system to start with -- and besides, we were genuinely curious to see if stress indeed leads to hair graying. "

Narrowing down the culprit

Because stress affects the whole body, researchers first had to narrow down which body system was responsible for connecting stress to hair color. The team first hypothesized that stress causes an immune attack on pigment-producing cells. However, when mice lacking immune cells still showed hair graying, researchers turned to the hormone cortisol. But once more, it was a dead end.

"Stress always elevates levels of the hormone cortisol in the body, so we thought that cortisol might play a role," Hsu said. "But surprisingly, when we removed the adrenal gland from the mice so that they couldn't produce cortisol-like hormones, their hair still turned gray under stress."

After systematically eliminating different possibilities, researchers honed in on the sympathetic nerve system, which is responsible for the body's fight-or-flight response.

Sympathetic nerves branch out into each hair follicle on the skin. The researchers found that stress causes these nerves to release the chemical norepinephrine, which gets taken up by nearby pigment-regenerating stem cells.

Permanent damage

In the hair follicle, certain stem cells act as a reservoir of pigment-producing cells. When hair regenerates, some of the stem cells convert into pigment-producing cells that color the hair.

Researchers found that the norepinephrine from sympathetic nerves causes the stem cells to activate excessively. The stem cells all convert into pigment-producing cells, prematurely depleting the reservoir.

"When we started to study this, I expected that stress was bad for the body -- but the detrimental impact of stress that we discovered was beyond what I imagined," Hsu said. "After just a few days, all of the pigment-regenerating stem cells were lost. Once they're gone, you can't regenerate pigment anymore. The damage is permanent."

The finding underscores the negative side effects of an otherwise protective evolutionary response, the researchers said.

"Acute stress, particularly the fight-or-flight response, has been traditionally viewed to be beneficial for an animal's survival. But in this case, acute stress causes permanent depletion of stem cells," said postdoctoral fellow Bing Zhang, the lead author of the study.

Answering a fundamental question

To connect stress with hair graying, the researchers started with a whole-body response and progressively zoomed into individual organ systems, cell-to-cell interaction and, eventually, all the way down to molecular dynamics. The process required a variety of research tools along the way, including methods to manipulate organs, nerves, and cell receptors.

"To go from the highest level to the smallest detail, we collaborated with many scientists across a wide range of disciplines, using a combination of different approaches to solve a very fundamental biological question," Zhang said.

The collaborators included Isaac Chiu, assistant professor of immunology at Harvard Medical School who studies the interplay between nervous and immune systems.

"We know that peripheral neurons powerfully regulate organ function, blood vessels, and immunity, but less is known about how they regulate stem cells," Chiu said.

"With this study, we now know that neurons can control stem cells and their function, and can explain how they interact at the cellular and molecular level to link stress with hair graying."

The findings can help illuminate the broader effects of stress on various organs and tissues. This understanding will pave the way for new studies that seek to modify or block the damaging effects of stress.

"By understanding precisely how stress affects stem cells that regenerate pigment, we've laid the groundwork for understanding how stress affects other tissues and organs in the body," Hsu said. "Understanding how our tissues change under stress is the first critical step towards eventual treatment that can halt or revert the detrimental impact of stress. We still have a lot to learn in this area."

Researchers have found how an antibiotic used to treat a debilitating gut infection stays put inside the body giving it time to effectively treat the problem, a discovery that will pave the way for the development of more effective antibiotic treatments to fight superbugs.

PE (pseudomembranous colitis) is a debilitating inflammation of the colon caused by infection with the microbe Clostridium difficile (and sometimes Staphylococcus aureus). The sugar- or carbohydrate-containing antibiotic known as vancomycin is taken by mouth to kill the infecting microbe.

To be effective, vancomycin needs to stay in the GI tract (gut) close to where it is needed and not be diluted away or lost through the lining of the gut and into the bloodstream. A multi-disciplinary team of scientists at the Universities of Nottingham and Leeds have now shown this 'staying put' mechanism is precisely what happens and that it can occur in an unexpected way.

Forming a formidable barrier

The research, published today in Scientific Reports shows that protein-carbohydrate molecules of the gut called mucins provide a formidable barrier helping to prevent the drug escaping using a unique mechanism of formation of large molecular complexes or clumps. The antibiotic and mucins join together to form a mucoadhesive complex, likely trapping the antibiotic within large complexes. It is the trapped vancomycin which the scientists believe may lead to delayed transit of the antibiotic leading to prolonged exposure of the antibiotic to the infectious C. difficile.

Dr Mary Phillips-Jones, Associate Professor in Polymer & Microbial Biophysics at the University of Nottingham led the research, she said: "Vancomycin is a precious 'last-line' antibiotic in the clinician's arsenal of therapies to fight several important pathogens including MRSA, pneumonia, as well as C. difficile. The clumping effect with gut mucins revealed in our study not only gives new information about what may happen when the antibiotic is given orally, but might also provide new insights into its behaviour when infused into patients suffering from other life-threatening infections."

The findings also fit with other studies which show that oral vancomycin produces high levels of vancomycin resistance amongst some gut bacteria (VRE), contributing to the generation of antimicrobial resistance (a serious concern); the clumping/ complexation phenomenon may therefore provide the first explanation of a mechanism by which this VRE generation occurs. But the benefits of taking oral vancomycin at the right time and when appropriate still outweigh any negative generation of antimicrobial resistance, and the study highlights that it is wise to take vancomycin when your GP advises it is good to do so.

Dr Stephen Harding, Professor of Applied Biochemistry at the University of Nottingham added: "The antibiotic vancomycin is a truly remarkable molecule - a drug with its own mucoadhesive or sticky property which slows its transit through the gut right down giving maximum therapeutic effect and minimizing unused vancomycin being returned to the environment. If scientists are going to win the fight against anti-microbial resistance, joint institutional and interdisciplinary approaches like this successful one are going to prove crucial."

EUGENE, Ore. - Jan. 22, 2020 - Espresso delivers a desired jolt of caffeine but getting a consistent good-taste is difficult. New research is offering a roadmap to reproducibility and a potential savings of $3.1 million a day for coffee shops across the United States.

In a new study, now online ahead of print in the journal Matter, a 10-member international team of researchers performed mathematical modeling and brewed hundreds of espresso shots to discover the key variables required to make consistently tasty coffee.

The general conclusions: Use less coffee at a courser grind than traditionally recommended, and brew it faster using less water than current practices.

That approach, the team concluded, reduces the amount of coffee used in espresso by 25 percent, saves coffee shops 13 cents per espresso-based drink and could make the industry more sustainable by reducing waste.

In the United States, alone, 124 million espresso-based drinks are consumed daily. From each bag of beans, a buyer realizes only about 18 to 22 percent of the mass getting into their coffee.

The approached gleaned from the research would allow extraction yields above that 22 percent level, said co-author Christopher H. Hendon, a chemist at the University of Oregon.

"We want to extract more from the coffee to save money, and be sustainable, but we also want it to taste delicious, not burnt or bitter," he said. "Our method allows us to push extractions and have the shots taste great, while being more sustainable and saving money."

And that, he said, would benefit the industry.

"For the local shop owner, this is an opportunity to save a lot of money without sacrificing quality," he said. "For the roaster, this is an opportunity to reflect on the approach to roasting and how people are brewing their coffee. For the producer, this should encourage them continue to produce high-quality coffee that can earn them the most money, knowing that more people will have access to it."

The research team - chemists, mathematicians and coffee professionals from five countries - analyzed grind size, water pressure, flow rate, amount of coffee and extraction kinetics to seek an optimum extraction yield - the percentage of coffee that gets into a shot of espresso. The recipe that emerged from the experiments, done in Brisbane, Australia, were tested in a Eugene coffee shop.

"The real impact of this paper is that the most reproducible thing you can do is use less coffee," Hendon said. "If you use 15 grams instead of 20 grams of coffee and grind your beans coarser, you end up with a shot that runs really fast but tastes great. Instead of taking 25 seconds, it could run in 7 to 14 seconds. But you end up extracting more positive flavors from the beans, so the strength of the cup is not dramatically reduced. Bitter, off-tasting flavors never have a chance to make their way into the cup."

The key to improving espresso reproducibility, Hendon said, is to determine which grind setting enables a maximum extraction from the coffee, and still tastes good.

In practice though, Hendon said, baristas typically find a grind setting on their equipment that produces the most concentrated, reproducible coffee, then modify the mass of water being used. That usually involves a reduction in shot volume to get a desired flavor. However, if the volume is too small, he said, an operator should grind coarser and repeat the volume-reduction process to reach a bigger drink of lower concentration but reproducibly tasty.

"Our model lets us take the leap from a very small particle size, less than the size of a hair, and solve a series of equations that tell us how much mass can be transported out of these little particles," said co-author Jamie M. Foster of the School of Mathematics and Physics at the University of Portsmouth in the United Kingdom.

In their modeling, the researchers drew on electrochemistry, likening how caffeine and other molecules dissolve out of coffee grounds to how lithium ions move through the electrodes of a battery. Borrowing modeling methodologies from battery work led to a rigorous coffee extraction model capable of making powerful and testable predictions.

Fine-tuning that formula for consumers, including those who brew their own espresso at home, however, requires human taste preferences to identify a sweet spot of consistent taste, which can vary from person to person and coffee to coffee, Hendon said. Baristas and home connoisseurs will need to use their judgment and experiment with their grinder and coffee-shop recipes to obtain consistent results.

"A good espresso beverage can be made in a multitude of ways," he said. "The point of this paper was to give people a map for making an espresso beverage that they like and then be able to make it 100 times in a row."

NMDARs (N-methyl-D-aspartate receptors) serve as valves on nerve cells, controlling the flow of electrical signals in the brain. This special group of receptors is suspect in many neurological diseases, including Alzheimer's, epilepsy, stroke, and Parkinson's. Biologists from Cold Spring Harbor Laboratory (CSHL) and chemists from the University of Bristol have joined forces, creating a chemical compound to enable more precise investigation of NMDAR activity.

In the latest issue of Nature Communications, CSHL Professor Hiro Furukawa and colleagues detailed how they identified and perfected a chemical compound that inhibits, or stops the activity of certain NMDARs. By inhibiting some NMDARs while letting others function, researchers can now identify the roles different types of NMDA receptors play in both healthy and diseased brains.

Jue Xiang Wang, a graduate of CSHL's Ph.D. program who helped lead the research, explained that the CSHL-Bristol team investigated how the novel compound UBP791 targets a pair of NMDAR subunits called GluN2C and GluN2D.

"There is evidence that GluN2C and GluN2D are relevant in the same brain regions where motor functions are affected by Parkinson's disease," she said. "Without good inhibitors, we could only speculate on what the 2C and 2D receptors do."

By inhibiting the activity of GluN2C and GluN2D receptors with higher efficiency and specificity than before, scientists can better study the role that they play in Parkinson's.

Video: https://www.youtube.com/watch?v=HQb2VczogL8

Furukawa's lab worked with Professor David Jane's chemistry lab at the University of Bristol to improve the NMDAR-targeting compound. The CSHL lab specializes in visualizing the physical structure of NMDARs using a technique called X-ray crystallography. Knowing the structure of the receptor was critical for the chemists, who were then able to design UBP791 to connect specifically with the GluN2C and GluN2D receptors much like how a key is made to fit into specific locks. Studying what makes UBP791 fit particularly well further allowed the scientists to improve the compound, creating its latest version, UBP1700.

The UBP1700 compound is more precise than any of its predecessors and "it's also more potent," said Wang. "That's important because researchers will only need small amounts of the compound to shut down the targeted receptors. This limits the potential for side-effects that the compound might produce."

Moving forward, Furukawa's lab and their Bristol collaborators will be working on further refining the new compound for use in research.

A new study from researchers at Columbia University Vagelos College of Physicians and Surgeons found that non-medical cannabis use--including frequent or problematic use--is significantly more common in adults with pain than in those without pain.

The findings were published in the American Journal of Psychiatry.

Since 1996, 34 states have passed medical marijuana laws and 11 states have legalized recreational cannabis use.

Studies indicate that heavy cannabis use increases the risk of vehicle accidents, respiratory and psychiatric symptoms, and cannabis use disorder.

"Despite this evidence, many people view cannabis use as harmless, and non-medical use of cannabis on a daily or near-daily basis has increased," says Deborah Hasin, PhD, a professor of epidemiology in the Department of Psychiatry at Columbia University Vagelos College of Physicians and Surgeons who led the current study. "In our study, we hoped to identify factors--such as pain--that may increase the risk of cannabis use disorder."

Hasin and colleagues analyzed data on marijuana use from the National Epidemiologic Surveys on Alcohol and Related Conditions in 2001-2002 and 2012-2013. The researchers compared non-medical cannabis use patterns in adults with and without pain (approximately 20% of participants in both surveys had moderate to severe pain).

Overall, non-medical marijuana use increased from about 4% in 2002 to 9.5% in 2013. In addition, in the most recent survey, those with pain were significantly more likely to engage in frequent non-medical cannabis use than those without pain (5.0% vs. 3.5%). The risk of cannabis use disorder was also significantly higher in those with pain (4.2% vs. 2.7%).

"Although meta-analyses of cannabis for treating pain show only mixed efficacy, particularly for plant marijuana, 66% of adults now view marijuana as beneficial for pain management. Given that about 20% of the adult population experienced moderate to severe pain, this puts a large group of U.S. adults at risk for frequent non-medical use and cannabis use disorder. Greater balance is needed in media reporting of marijuana issues, including messages that convey credible information about the nature and magnitude of health risks from non-medical cannabis use, including among the large group of US adults with pain," says Hasin. "Psychiatrists and other mental health professionals treating patients with pain should monitor their patients for signs and symptoms of cannabis use disorder."

The paper is titled "US adults with pain, an increasingly vulnerable group for non-medical cannabis use and cannabis use disorder: 2001-2002 and 2012-2013."

Mathematicians, physicists and materials experts might not spring to mind as the first people to consult about whether you are brewing your coffee right.

But a team of such researchers including Dr Jamie Foster, a mathematician at the University of Portsmouth, are challenging common espresso wisdom.

They have found, that fewer coffee beans, ground more coarsely, are the key to a drink that is cheaper to make, more consistent from shot to shot, and just as strong.

The study is published in the journal Matter.

Dr Foster and colleagues set out wanting to understand why sometimes two shots of espresso, made in seemingly the same way, can sometimes taste rather different.

They began by creating a new mathematical theory to describe extraction from a single grain, many millions of which comprise a coffee 'bed' which you would find in the basket of an espresso machine.

Dr Foster said: "In order to solve the equations on a realistic coffee bed you would need an army of super computers, so we needed to find a way of simplifying the equations.

"The hard mathematical work was in making these simplifications systematically, in such a way that none of the important detail was lost.

"The conventional wisdom is that if you want a stronger cup of coffee, you should grind your coffee finer. This makes sense because the finer the grounds mean that more surface area of coffee bean is exposed to water, which should mean a stronger coffee."

When the researchers began to look at this in detail, it turned out to be not so simple. They found coffee was more reliable from cup to cup when using fewer beans ground coarsely.

"When beans were ground finely, the particles were so small that in some regions of the bed they clogged up the space where the water should be flowing," Dr Foster said.

"These clogged sections of the bed are wasted because the water cannot flow through them and access that tasty coffee that you want in your cup. If we grind a bit coarser, we can access the whole bed and have a more efficient extraction.

"It's also cheaper, because when the grind setting is changed, we can use fewer beans and be kinder to the environment.

"Once we found a way to make shots efficiently, we realised that as well as making coffee shots that stayed reliably the same, we were using less coffee."

The new recipes have been trialled in a small US coffee shop over a period of one year and they have reported saving thousands of dollars. Estimates indicates that scaling this up to encompass the whole US coffee market could save over $US1.1bn dollar per year.

Previous studies have looked at drip filter coffee. This is the first time mathematicians have used theoretical modelling to study the science of the perfect espresso - a more complicated process due to the additional pressure.

CHAPEL HILL, NC - January 22, 2020 - Approximately 38 million people are infected with HIV worldwide, about 1.1 million people in the United States. Currently, people with HIV take antiretroviral therapy (ART), which can suppress HIV to undetectable levels in blood, but the virus persists throughout the body in latently infected resting CD4+ T cells. The immune system cannot recognize these cells and no current therapies can eliminate them. When ART is stopped, viral loads spike in blood. This is why people with HIV must take ART continuously, and this latent reservoir is considered the greatest obstacle to a cure.

Now, scientists from the University of North Carolina at Chapel Hill and Emory University used a compound called AZD5582 to activate latently infected CD4+ T cells at impressive levels in blood and many different tissues with no or very little toxicity.

Published in Nature, this seminal work was accomplished at the UNC School of Medicine in ART-suppressed mouse models with fully functioning human immune cells, the kind typically infected with HIV in humans. Importantly, this research was then extended in a longitudinal, multi-dose study at Emory University in ART-suppressed rhesus macaques infected with Simian Immunodeficiency Virus (SIV). Qura Therapeutics, a partnership between scientists at UNC-Chapel Hill and ViiV Healthcare, conducted the basic science investigations that expedited the work in animal models. More research is needed before testing could begin in humans, but this work is considered a significant scientific step toward developing curative therapies.

"Previously, no one had successfully tested a latency reversal molecule in humans or in an animal model with human cells demonstrating systemic HIV induction in peripheral blood, in resting CD4+ T cells from multiple tissues, and then replicated this success in a completely different species infected with a different virus," said co-senior author J. Victor Garcia, PhD, director of the International Center for the Advancement of Translational Science, professor of medicine and microbiology & immunology at the UNC School of Medicine.

Ann Chahroudi, MD, PhD, associate professor of pediatrics at Emory and director of the Center for Childhood Infections & Vaccines at Emory and Children's Healthcare of Atlanta, is co-senior author. "AZD5582 was remarkable in its ability to reactivate latent SIV from resting CD4+ T cells, and to induce continued virus production in the blood when monkeys were still receiving daily antiretroviral therapy," she said. "This is an exciting scientific achievement, and we hope this will be an important step toward one day eradicating the virus in people living with HIV."

This work was made possible by the Collaboratory of AIDS Researchers for Eradication (CARE) housed at UNC-Chapel Hill and part of the Martin Delaney Collaboratories for HIV Cure Research - the flagship HIV cure research program supported by the National Institutes of Health (NIH) - the Emory Consortium for Innovative AIDS Research (E-CIAR) in Nonhuman Primates, also supported by NIH, Qura Therapeutics, and ViiV Healthcare.

For several years, scientists have been trying various latency reversal agents to induce HIV out of latency so it becomes visible to the immune system, allowing an antiviral immune response to kill the virus-infected cells. Some agents focused on activating the canonical NF-kB pathway in CD4+ T cells to drive infected cells out of latency. But triggering that pathway involved many hundreds of genes, making such an aggressive approach too toxic.

Scientists at Qura Therapeutics - a partnership between UNC-Chapel Hill and ViiV Healthcare - turned their attention to the non-canonical NF-kB pathway in CD4+ T cells.

Co-senior author Richard Dunham, PhD, lead investigator at Qura Therapeutics, led studies with patients' cells necessary to show that AZD5582, a mimetic of the Second Mitochondrial Activator of Caspases (SMACm), could serve as an effective latency reversal agent. AZD5582 provides a gradual but persistent activation of the non-canonical NF-kB pathway while triggering fewer human genes than other latency reversal agents, potentially making it much less toxic.

"We are excited that we now, for the first time, have a simple, tractable tool to test the long-standing hypothesis that activating latent HIV can expose the viral reservoir to clearance," said Dunham, Director of HIV Cure at ViiV Healthcare.

UNC scientists led by Garcia, an Oliver Smithies Investigator and member of the UNC Center for AIDS Research, then tested AZD5582 in vivo using ART-suppressed mouse models that contain human CD4+ T cells in tissues throughout the body. Garcia and colleagues documented increases in viral RNA expressed in blood and nearly all tissues, including lymph nodes, thymus, bone marrow, liver, lung, and brain. In some cases, the viral RNA increase was more than 20 fold.

At Emory, Chahroudi and colleagues tested AZD5582 in ART-suppressed, SIV-infected macaques and found similar results, this time with multiple, weekly doses. They observed a spike in RNA expression in lymph nodes and blood of the primates, marking the first time a latency reversal agent accomplished this feat with little toxicity in both animal models used to study HIV.

In a second paper in the same issue of Nature, Emory researchers led by Guido Silvestri, MD and Chahroudi in collaboration with UNC researchers, accomplished latency reversal in a different way. They injected an antibody into nonhuman primates with ART-suppressed SIV infection to deplete CD8+ T cells, which are very important for controlling the infection. Then the researchers administered an altered version of the cytokine IL-15 to show that this combination pushed viral RNA to appear in blood and tissue where it previously had not been seen. Garcia and UNC colleagues confirmed these results for HIV in the same type of mouse model in which AZD5582 was tested.

While it is not yet clear if the strategy of depleting CD8 cells could be translated into humans, this result opens new ways to understand how HIV is controlled, and how its expression might be manipulated. .

Taken together, these findings demonstrate the power of science conducted across teams, across institutions, and between industry and academic partners. The Nature studies show that HIV can be pushed out of hiding - confirmed across different model systems - and the studies open a range of possibilities for the development of new therapies that might one day lead to a cure for HIV.

This release has been removed upon request of the submitting institution. Please contact Heloisa Helena Reinert here: Hreinert@fapesp.br, 55 11 3838-4151.

Everyone hates road construction, even the soils and bodies of water around the roads. Paved roads can't absorb water, so that responsibility falls to the soil next to the road. Unfortunately, those soils are often damaged during construction.

Water that runs off roads can contain harmful contaminants. If that water doesn't infiltrate into nearby soil, those contaminants can make their way into bodies of water and be harmful. Rich McLaughlin and his research team at North Carolina State University have been working on how to help soil be healthy and happy after road construction.

Over the years, McLaughlin's team noticed contractors were trying to grow grass on soils near roads after construction. They noticed this didn't seem to be working well. So, they began to test the soils. Results showed the soils were very compacted and little water was getting down into the soil.

"Not only did this compaction prevent grass from growing, much of the unpaved area beside the road was shedding water as quickly as paved roads and roofs," McLaughlin explains. "Over the past decade, we have worked to help grass become better established after construction. This also means that water can better infiltrate into these soils."

Most recently, the team has been studying the benefits of tilling and adding things, called amendments, to the soil. They want to see if this can help reduce the amount of runoff. This runoff can contain heavy metals, petroleum products, sediment, and excess nutrients. These would normally run into the stormwater system.

In a recent study, they established plots next to roads where they could try different treatments and collect runoff from the soil. Researchers inserted barriers into the soil around each plot to send the runoff into a pipe, connected to a collection tub.

They found that tilling the soil and sometimes adding compost could greatly improve the infiltration for years after it was applied. On soils that had vegetation for many years, the improvements were less dramatic (but still considerable).

"Previous studies indicated that a good stand of vegetation helps maintain the high infiltration rates generated by tillage, and that's the main benefit," McLaughlin says. "Water and contaminant uptake by the plants is helpful, but the effects on soil's physical properties is the most important."

Part of their recent work tested two different kinds of vegetation: grasses and wildflowers. Grasses are cheaper and quicker to establish but need to be mowed three or four times per year. The wildflowers seemed to help improve infiltration a bit more than grasses.

Wildflowers can also provide food and habitat for important pollinators like butterflies, which are in decline worldwide. They are also mowed less, cutting down on compaction from mower wheels. The researchers think the added benefit might be coming from the roots of the wildflower plants but haven't tested this thoroughly.

McLaughlin adds that as the human population grows and more roads are constructed, it's becoming important to manage this runoff. Helping runoff trickle down into soils where possible is one of the easiest ways to tackle the problem. The next step in the research is trying different wildflower types and mixes to test their effects.

"Improving soil physical conditions through tillage and amendments is what a typical gardener might do," he says. "The key factor, however, is that vigorous plant growth immediately after tillage is needed to maintain that condition, and no further tillage or amendments are needed. I'm always looking for ways to improve water quality in our lakes, streams, and estuaries because I enjoy all kinds of water-oriented activities, none of which are enjoyable in polluted waters."

McLaughlin presented his research at the 2019 International Annual Meeting of the American Society of Agronomy, Crop Science Society of America and Soil Science Society of America. This research was supported by the North Carolina Department of Transportation Roadside Environmental Unit.

New research from Cass Business School has found that business sustainability strategies can succeed alongside mainstream competitive strategies when managers believe in them.

In 'Toward a Process Theory of Making Sustainability Strategies Legitimate in Action', published in the Academy of Management Journal, the researchers found that although managers support sustainability strategies, there can be tensions in goals, values, and in product features. This can occur when implementing them alongside the mainstream strategy, creating the potential for 'decoupling' - where organisations adopt policies symbolically, without implementing them substantially.

However, they found that working through these tensions on specific tasks helps to overcome them. Resolving tensions reinforces the organisational-level legitimacy of the strategy and its integration within the mainstream strategy.

The three-year qualitative study focused on the implementation of a new sustainability strategy alongside a mainstream strategy at TechPro, a market-leading global manufacturer with 20,000 full-time employees and an annual revenue of $3.5 billion (USD). While the company had no existing sustainability strategy, it had a long history of placing a high premium on corporate values such as 'trustworthiness' and 'truthfulness' which guided the firm's environmental and social standards. The new sustainability strategy was popular with staff, who were keen to demonstrate their own values through its implementation.

While the new strategy focused on addressing TechPro's social and environmental responsibilities in product policy and staff behaviour, their existing mainstream strategy focused on the competitive objectives and targets associated with defending their market position. For example, improving operational efficiency to ensure competitive pricing and maintaining, and growing, market share.

Tensions arose when managers tried to implement the sustainability strategy alongside the mainstream strategy, in their day-to-day operations. Tensions were in three areas:

Between strategic goals when there was incompatibility between tasks involving both organisational environmental compliance and organisational profit.

Between product features where there was incompatibility in incorporating the sustainability and mainstream strategy features in the technical design of a product or in production process. For example, by choosing materials that were cost friendly versus environmentally friendly.

Between organisational values, defined as between competitive orientation versus social orientation and competitive products versus trustworthy products.

The researchers found that workers could resolve these tensions to carry out the two strategies in three ways:

Mutually adjusting by compromising and reinterpreting or splitting between the strategies, when they could not physically incorporate both into a product or product development process.

Prioritising the sustainability strategy over the mainstream strategy on values-driven tasks, so enabling differentiation between the tasks, while not inhibiting wider integration of the strategies within the organisation.

Combining them within a common purpose and by including the new sustainability strategy within their existing procedures.

Sustainability has become a strategic priority for companies worldwide as consumers, shareholders and employees become more environmentally and socially aware, said report co-author, Professor Paula Jarzabkowski of Cass Business School.

"Prioritising sustainability strategies can simultaneously enhance an organisation's competitiveness and its social agenda," she said.

"However, although the sustainability strategy was seen as the right thing to do, the company was also faced with rising cost pressures and a battle to maintain market leadership so it was difficult to implement both strategies at the same time."

Professor Jarzabkowski said the research was particularly interesting as TechPro is a leading global manufacturer of the kind of high-end goods that many of us have in our homes, rather than a traditional social enterprise which tend to already have an inbuilt sustainability strategy within their business.

"Surprisingly, we found that rather than suppress the sustainability strategy, or do only the minimum, sometimes TechPro managers prioritized it over competitive actions they could have taken," she said.

"This research gives us hope. If a mainstream global business with a huge market share and presence in households around the world can develop, and implement, a successful sustainability strategy alongside their mainstream strategy, then other businesses can do the same. This means that more firms are more environmentally and socially aware and this understanding will have positive benefits for people, planet and profit."

Professor Jarzabkowski said the support that managers and workers gave the sustainability strategy was also crucial to its success.

"Their belief in, and commitment to, incorporating sustainability within the business played a significant part in the success of both strategies."

ANN ARBOR--Fully vaccinating children reduces the risk of hospitalization associated with influenza by 54%, according to a study by researchers at the University of Michigan, the Clalit Research Institute, and Ben-Gurion University in Israel.

The study, published in the December 2019 issue of the journal Clinical Infectious Disease, is one of the few studies worldwide that has tested the effectiveness of childhood vaccination against influenza and risk of hospitalization due to influenza complications.

In Israel, as in the United States, government guidelines recommend that children 8 or younger who have never been vaccinated, or who have only gotten one dose of flu vaccine previously, should receive two doses of vaccine.

Children vaccinated according to government guidelines are much better protected from influenza than those who only receive one vaccine, said Hannah Segaloff, a research fellow at the U-M School of Public Health and lead author of the study.

"Over half of our study population had underlying conditions that may put them at high risk for severe influenza-related complications, so preventing influenza in this group is critically important," she said. "Our results also showed that the vaccine was effective in three different seasons with different circulating viruses, reinforcing the importance of getting an influenza vaccine every year no matter what virus is circulating."

The retrospective study used data from Clalit Health Services, the largest health fund in Israel, to review the vaccination data of 3,746 hospitalizations of children 6 months to 8 years old at six hospitals in Israel. They were tested for influenza over three winter seasons 2015-16, 2016-17 and 2017-18.

Not only do the findings reveal that the flu vaccine reduced hospitalizations associated with the flu by 54%, but they show that giving two vaccine doses to children up to age 8 who have never been vaccinated or only received one dose previously is more effective than administering one dose, in accordance with the Israel Ministry of Health's recommendations.

"Young children are at high risk of hospitalization due to influenza complications," said study co-author Mark Katz, a senior researcher at the Clalit Research Institute, the research arm of Clalit Health Services, and an adjunct associate clinical professor at the BGU School of Public Health and Medical School for International Health.

"Children with underlying illnesses such as asthma and heart disease have an even greater risk of getting the complications. It is important to prevent influenza infections in these populations."

The findings support health organizations' recommendations, including the Israel Ministry of Health to vaccinate children against influenza every year, preferably before the onset of winter or early childhood. Children under 5 are defined as having a high risk of influenza complications.

"This study mirrors a previous study we conducted at Clalit Institute where we found that flu vaccine reduces 40% risk of hospitalizations in pregnant women," said Ran Balicer, director of the Clalit Research Institute and professor at the BGU School of Public Health.

"It reaffirms that vaccination is the most effective way to prevent both the flu and hospitalization. We hope parents will be aware of these facts and make an informed decision about the importance of vaccinating their children."

In a range of experiments, scientists have reactivated resting immune cells that were latently infected with HIV or its monkey relative, SIV, in cells in the bloodstream and a variety of tissues in animals. As a result, the cells started making copies of the viruses, which could potentially be neutralized by anti-HIV drugs and the immune system. This advance, published today in two papers in the journal Nature, marks progress toward a widely accessible cure for HIV.

The new research was conducted by investigators from the Collaboratory of AIDS Researchers for Eradication (CARE) based at the University of North Carolina at Chapel Hill and from the Emory Consortium for Innovative AIDS Research (E-CIAR) in Nonhuman Primates, both funded by the National Institutes of Health. Scientists from ViiV Healthcare and Qura Therapeutics collaborated on the research. CARE is part of the Martin Delaney Collaboratories for HIV Cure Research, the flagship NIH-supported HIV cure research program. The joint efforts of scientists from a variety of specialties made the new findings possible.

"A simple, safe and scalable cure for HIV is an aspirational goal that, if achieved, would accelerate progress toward ending the HIV pandemic," said Anthony S. Fauci, M.D., director of the National Institute of Allergy and Infectious Diseases, part of NIH. "These new findings help sustain our cautious optimism that an HIV cure is possible."

While consistent antiretroviral therapy (ART) maintains the health of people living with HIV and prevents transmission of the virus, it is not a cure. Developing an HIV cure has been extremely difficult due to the persistence of viral reservoirs, where the virus hides from the immune system. These reservoirs consist of HIV-infected cells containing HIV genetic material that can generate new virus particles if a person's treatment is interrupted. The cells have entered a resting state that they maintain until they are activated to produce the virus. The immune system cannot recognize and kill HIV-infected cells in a resting state, and ART has no effect on them.

Consequently, scientists have been attempting to activate the HIV reservoir so therapeutic agents or an enhanced immune system can recognize and kill the infected cells, eliminating HIV. This strategy is often called "kick and kill." Previous attempts to reactivate or "kick" the HIV reservoir worked well in the laboratory but were either ineffective or too toxic when tested in animals and people.

One of today's reports describes the testing of a compound called AZD5582, which belongs to a class of molecules that have proven safe as experimental cancer therapeutics.

CARE scientists obtained 20 mice with human immune systems, infected the animals with HIV, and then gave them ART that suppressed the virus. Next, the scientists injected AZD5582 into 10 of the mice and a placebo into the other 10.

Within 48 hours, high levels of HIV RNA were detected in the blood of six of the AZD5582-treated mice. HIV RNA levels in resting immune cells of the bone marrow, thymic organoid, lymph node, spleen, liver and lung were up to 24-fold higher in the AZD5582-treated mice than in the controls. This indicated that AZD5582 had activated resting cells in the HIV reservoir throughout the treated mice. The compound did not cause toxicity in the mice or activate their immune systems.

The E-CIAR and CARE investigators also obtained 21 rhesus macaques, infected them with SIV and gave them suppressive ART. More than a year after the monkeys began ART, the scientists gave 12 of them weekly intravenous infusions of AZD5582 for either three or 10 weeks.

The level of SIV increased in the blood of five of the nine monkeys (55%) that received 10 doses of AZD5582 and in none of the three monkeys that received fewer doses. Thus, SIV levels increased in five of 12 monkeys (42%) overall, even as they remained on ART. SIV RNA levels in resting immune cells from the monkeys' lymph nodes were significantly higher in animals treated with 10 doses of AZD5582 than in the nine monkeys that did not receive the compound. The investigators found AZD5582 treatment to be safe for most of the monkeys. The scientists did not detect a consistent reduction in the size of SIV reservoir in the AZD5582-treated monkeys, however, suggesting that it may be necessary to pair the compound with another agent to kill activated reservoir cells.

The researchers have begun additional animal studies to determine the best dose and timing of treatment and to be sure AZD5582 activates the reservoirs of many different HIV and SIV strains. It also will be important to test other compounds in the same class as AZD5582 to determine which might work best in humans, according to the scientists. If the results of these follow-up studies are successful, a preliminary clinical trial of treatment with AZD5582 or a related compound in people living with HIV may follow.

This study was led by J. Victor Garcia, Ph.D., Ann Chahroudi, M.D., Ph.D., and Richard Dunham, Ph.D. Dr. Garcia is director of the International Center for the Advancement of Translational Science, an Oliver Smithies Investigator and a professor of medicine, microbiology and immunology at University of North Carolina at Chapel Hill. Dr. Chahroudi is an associate professor of pediatrics in the division of pediatric infectious diseases Emory University School of Medicine and director of the Emory + Children's Center for Childhood Infections and Vaccines. Dr. Dunham is a director at ViiV Healthcare and an adjunct assistant professor at University of North Carolina at Chapel Hill.

The other new report published today describes how a combination of two agents strongly activated the SIV reservoir in ART-treated rhesus macaques and the HIV reservoir in ART-treated mice with human immune systems. One agent, an antibody called MT807R1, depletes the body of immune cells called CD8+ T cells. The other agent is an engineered protein complex called N-803, a more powerful version of a naturally occurring molecule that activates certain immune cells to fight pathogens.

E-CIAR scientists obtained 35 rhesus macaques, infected them with SIV and gave them ART, which suppressed the virus in 33 of the animals. At least a year after ART began, the scientists gave seven monkeys N-803 alone, 14 monkeys MT807R1 alone, and 14 monkeys both MT807R1 and N-803.

N-803 alone had no impact on the SIV reservoir. MT807R1 alone led to a moderate but significant increase in the level of SIV in the animals' blood (their viral load). But the combination of MT807R1 plus N-803 led to a robust and persistent increase in the SIV viral load of all 14 animals--even the six in which fewer than three copies of SIV were detected before the experimental treatment began.

CARE scientists at UNC replicated these outcomes in 23 mice that had been given human immune systems, infected with HIV and given suppressive ART.

In addition, investigators demonstrated in cell culture that N-803 could reactivate human immune cells latently infected with HIV, but that adding CD8+ T cells to the culture suppressed the latency-reversing activity of N-803.

Taken together, the findings illustrate that CD8+ T cells play a role in maintaining the SIV reservoir in monkeys. The scientists hope to clarify exactly how CD8+ T cells do this so they can develop a latency-reversing strategy that does not require eliminating all CD8+ T cells and is thus gentler on the body.

A team of researchers at CHU Sainte-Justine and Université de Montréal has shed light on the mechanisms that underlie a rare genetic condition by creating the first cellular model of the disease. The study's findings were published today in the Journal of Allergy and Clinical Immunology.

Chronic granulomatous disease (CGD) is a rare hereditary condition that affects one in every 217,000 people worldwide and typically strikes patients at an early age.

"It is a primary innate immune defect that typically leads to severe, recurrent infections caused by bacteria and fungi, as well as potentially disabling lung inflammation or inflammatory colitis similar to Crohn's disease," said senior author Dr. Fabien Touzot, a clinical assistant professor in pediatric medicine at UdeM and researcher in pediatric immunology and hematology at CHU Sainte-Justine.

"Currently, patients are forced to take antibiotics and anti-inflammatory drugs for the rest of their lives."

Gene editing shows the way forward

To better understand the mechanisms that trigger inflammation in patients with CGD, Touzot and his research team created the very first cellular model of the disease in their labs at CHU Sainte-Justine. They then used a technique known as gene editing to recreate and introduce into their model a genetic mutation that causes the disease. This allowed them to model the inflammatory response observed in patients and to study its mechanisms.

"CGD is a hereditary illness caused by mutations in the NADPH oxidase enzyme. These mutations prevent white blood cells from working properly and, as a result, the patient's body can no longer defend itself against certain kinds of bacteria and fungi," said researcher Aissa Benyoucef, the study's first author.

"More than 90% of affected patients have inflammation that appears to be unrelated to infectious agents," he added. "Treating this inflammation is difficult, since it can put patients at increased risk of infection, which can sometimes be fatal. A better understanding of the mechanisms underlying the disease could help us develop new and more effective treatment strategies."

The research team showed that restoring NADPH oxydase function in defective cells would put the immune process back on track, thereby proving that this genetic mutation plays a direct role in causing inflammation.

"CHU Sainte-Justine is one of Quebec's leading centres of expertise in rare genetic diseases," said Touzot. "We're proud to serve patients by expanding the knowledge base in this area and by contributing to the development of precision medicine."

The new cellular model will be useful for the development of targeted treatments that are less toxic and more effective in treating inflammation, significantly improving patient quality of life, according to the researchers.