Warren symposium follows legacy of geneticist giant

If we want to understand how the brain creates memories, and how genetic disorders distort the brain’s machinery, then the fragile X gene is an ideal place to start. That’s why the Stephen T. Warren Memorial Symposium, taking place November 28-29 at Emory, will be a significant event for those interested in neuroscience and genetics. Stephen T. Warren, 1953-2021 Warren, the founding chair of Emory’s Department of Human Genetics, led an international team that discovered Read more

Mutations in V-ATPase proton pump implicated in epilepsy syndrome

Why and how disrupting V-ATPase function leads to epilepsy, researchers are just starting to figure Read more

Tracing the start of COVID-19 in GA

At a time when COVID-19 appears to be receding in much of Georgia, it’s worth revisiting the start of the pandemic in early 2020. Emory virologist Anne Piantadosi and colleagues have a paper in Viral Evolution on the earliest SARS-CoV-2 genetic sequences detected in Georgia. Analyzing relationships between those virus sequences and samples from other states and countries can give us an idea about where the first COVID-19 infections in Georgia came from. We can draw Read more

Department of Medicine

Tracing the start of COVID-19 in GA

At a time when COVID-19 appears to be receding in much of Georgia, it’s worth revisiting the start of the pandemic in early 2020. Emory virologist Anne Piantadosi and colleagues have a paper in Viral Evolution on the earliest SARS-CoV-2 genetic sequences detected in Georgia.

Analyzing relationships between those virus sequences and samples from other states and countries can give us an idea about where the first COVID-19 infections in Georgia came from. We can draw a few conclusions, such as: there was no “Patient Zero”, at least here.

According to sequence analysis in the paper, multiple early introductions of SARS-CoV-2 into Georgia occurred, probably coming from Asia, weeks before the first officially reported case in March 2020. The authors suggest that the early focus on returning international travelers was misplaced, as opposed to broader testing of patients with COVID-19 symptoms. Visit an urgent care facility if you experience symptoms of covid or any other viral infection.

“SARS-CoV-2 was likely spreading within the state for approximately three weeks prior to detection in either diagnostic or sequencing data,” the authors write.

Tree showing relationships between SARS-CoV-2 genetic sequences from Georgia and other states/countries

In Georgia, the subclade, or swarm of related viruses, that was dominant early on (called 19B) disappeared by the end of April, eclipsed by variants carrying the D614G mutation. This was an early hint – even before the emergence of B117/Alpha and other variants such as Delta and Omicron — that SARS-CoV-2 would evolve through competition. These virology studies need to be conducted in research labs or high-quality mobile CGMP cleanrooms to yield accurate results.

Similarly, sequence analysis from Washington state – the site of the first COVID-19 case identified in the United States — has shown that the first official case did not lead directly to the initial wave of infections there. The first wave actually fizzled out as a result of public health interventions, but other undetected infections in Washington in February 2020 led to sustained downstream transmission. 

The co-first authors of the Viral Evolution paper are Emory infectious disease specialist Ahmed Babiker and graduate student Michael Martin, with co-authors from the Centers of Disease Control and Prevention. The paper analyzes sequences from Emory Healthcare patients along with previously available sequences.

In a few cases, scientists attempted to trace relationships between infected patients who had recently travelled to other countries (Italy, Switzerland) or other states (Louisiana, Colorado), but the available data did not confirm all of those connections. 

Keep in mind that SARS-CoV-2 testing was very limited at the start of the pandemic, because of short supplies as well as FDA policy. More extensive virus sequencing efforts at Emory did not begin until mid-March 2020. With respect to viruses, we only see what we look for, and scientists can’t analyze samples they don’t have. If more samples were available from January or February, what would we find? Also, this paper’s analysis does not include any (known) samples from a February 2020 funeral in Albany, GA that was considered a “super-spreader event.” 

Two years later, has SARS-CoV-2 genomic surveillance improved? Piantadosi says that her team’s paper should be viewed in combination with their recent paperon the detection of the first Omicron case in Georgia, a woman who became sick in November 2021 while visiting Cape Town, South Africa.

 “That’s an example of where we did better,” Piantadosi says. “It does speak to how much surveillance has improved. We were conducting routine surveillance – not focusing on returning travelers.”

In the Omicron case, the woman in question first went to a community testing site, and those samples were not available for sequence analysis.

Piantadosi says that “we’ve achieved Phase I” – in that large hospitals or health systems such as Emory are collecting SARS-CoV-2 sequences, and the state Department of Public Health and large diagnostic services companies are also doing so. But as more SARS-CoV-2 testing is performed at home – generally a good thing for convenience and public health — surveillance for new variants needs to continue, she says.

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Poop substitute effective vs C. diff

A pill derived from human feces can effectively ward off Clostridium difficile diarrhea, according to the results of a clinical trial published in the New England Journal of Medicine.

Clinical microbiologist/infectious disease specialist Colleen Kraft and Emory patients contributed to the Phase III, 182 patient study, which was sponsored by Seres Therapeutics. Kraft is associate chief medical officer at Emory University Hospital and 2022 president-elect of the American Society for Microbiology.

Colleen Kraft, MD

Seres’ pill is an alternative to fecal microbiota transplant (FMT), a treatment for C.difficile that is both well-established and difficult to standardize. Everyone is intimately familiar with the material necessary for FMT, but its microbial components vary with the individual donor, diet and time. That presents some inconsistency and risk that has delayed FDA approval for the procedure.

Moving toward an “off the shelf” product, Seres takes stool from prescreened donors and treats the material with ethanol, killing some microbes and leaving behind bacterial spores that can compete for intestinal real estate with C. difficile. A previous study of Seres’ pill was unsuccessful, inspiring the headline “Sham poo washes out.” More information about the newer study and the company’s plans are in this Science article.

C. difficile colonization sometimes occurs after antibiotics deplete healthier forms of intestinal bacteria. Kraft and colleagues at Emory have been investigating whether FMT can prevent colonization by antibiotic-resistant bacteria in kidney transplant patients, who have (deliberately) dampened immune systems and need to take antibiotics.

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Report on first Omicron case detected in GA

The first Omicron case detected in Georgia through SARS-CoV-2 genomic surveillance probably became infected during a visit to Cape Town, South Africa, according to a recent case report in Clinical Infectious Diseases.

The patient was a woman in her 30s, who was fully vaccinated with Pfizer/BioNTech twice, then a booster in October 2021 – about six weeks before becoming sick. She had a negative PCR test shortly before traveling back to Georgia but developed symptoms around the time of her return flight.

The woman was diagnosed with COVID-19 at the end of November, a few days after her return to Georgia — just after Omicron was declared a Variant of Concern by the WHO.

This single case report is not representative of the overall severity of Omicron, which is generating a large number of infections, burdening hospitals in Georgia and elsewhere. The patient experienced muscle aches, nausea, fatigue and cough, but did not have a fever or shortness of breath and did not require hospitalization.

A view of Cape Town’s Table Mountain

The lead authors of the case report were Marybeth Sexton, chief quality officer for the Emory Clinic, and infectious disease specialist Jesse Waggoner. The senior author was viral geneticist Anne Piantadosi.

The authors note: “Identifying this case required eliciting an appropriate travel history and being able to identify and perform sequencing for COVID patients in the community, since the patient had mild symptoms and did not seek clinical care.”

To speed detection of SARS-CoV-2 variants such as Omicron, the case report contains information about how to customize the “Spike SNP” PCR assay to give results within a few hours, rather than waiting for full viral sequencing taking 72 hours.

With the help of virologist Mehul Suthar’s lab, the authors were also able to report that the patient developed high levels of antiviral antibodies capable of neutralizing the Omicron variant. Currently available booster shots can elicit measurable antiviral antibody activity (see our recent post Thrice is nice), but actual Omicron infection generates way more.

Posted on by Quinn Eastman in Immunology Leave a comment

Two items relevant to long COVID

One of the tricky issues in studying in long COVID is: how widely do researchers cast their net? Initial reports acknowledged that people who were hospitalized and in intensive care may take a while to get back on their feet. But the number of people who had SARS-CoV-2 infections and were NOT hospitalized, yet experienced lingering symptoms, may be greater.

A recent report from the United Kingdom, published in PLOS Medicine, studied more than 270,000 people using electronic health records. This research found that more than a third of patients had one or more features of long COVID three to six months after COVID-19 diagnosis.

That would be consistent with recently published findings from Emory, which surveyed 290 people from a telemedicine program: Emory Healthcare’s Virtual Outpatient Management Clinic. Almost 40 percent reported persistent symptoms. However, none of the individual symptoms, such as fatigue, mental fog or difficulty breathing, were reported at a rate of more than about 20 percent.

With this survey, Emory investigators were trying to capture the larger number of people out there who were recovering from COVID-19, without selecting for people who are especially miserable (to put it bluntly). Initial symptom severity predicted the likelihood of long-term symptoms, but there were outliers from this trend. This was a cross-sectional but not longitudinal study. One intriguing finding was that people with hypertension were less likely to experience persistent COVID symptoms, which may have to do with ACE inhibitors, common anti-hypertension drugs.

The second item reports data on autoantibodies from a long COVID cohort at Emory, from immunologists Ignacio Sanz and Eun-Hyung Lee. Autoantibodies are a feature of autoimmune diseases, such as lupus and rheumatoid arthritis, and their presence in long COVID may explain persistent symptoms such as fatigue, skin rash and joint pain.

Several research groups have shown that autoantibodies can result from the intense inflammation of COVID-19 (examples outside Emory here, here), which breaks down the guardrails that normally constrain immune cells from attacking the body itself. But a key question is: how long does that deranged state last? And do autoantibodies correlate with persistent symptoms? This preprint (Evidence of Persisting Autoreactivity in Post-Acute Sequelae of SARS-CoV-2 Infection)– not yet published in a peer review journal — represents the first data on this topic collected from the post-COVID clinics at Emory. More to come on this topic.

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Straight to the heart: direct reprogramming creates cardiac “tissue” in mice

Bypassing stem cells, Emory scientists can now create engineered heart tissue by directly reprogramming connective tissue cells in mice. The findings could provide new avenues for a quest many cardiologists have pursued: repairing the damaged heart like patching a roof. 

The results were published in Nature Biomedical Engineering

“This is the first study demonstrating direct tissue reprogramming from single adult cells from the body,” says senior author Young-sup Yoon, MD, PhD, professor of medicine at Emory University School of Medicine.

The research could potentially provide therapeutic options for millions of people with heart failure or other conditions. If heart muscle is damaged by a heart attack, the damaged or dead cells do not regenerate. Other scientists have shown they can create human heart tissue from induced pluripotent stem cells (example), but the Emory team showed that it is possible to avoid stem cells and the technologies required to create them, such as viruses. 

“Direct reprogramming into tissues that contain multiple cell types has not previously been reported, and it could open new pathways in the regenerative medicine field, this could mean new findings regarding stem cell therapy for als” Yoon says. “It could serve as a platform for cell-based therapy by avoiding the problems of current stem cell-based approaches, and for disease modeling and drug development.”

First author Jaeyeaon Cho, PhD – currently at Yonsei University

Yoon is also part of the Wallace H. Coulter Department of Biomedical Engineering at Georgia Tech and Emory. First author Jaeyeaon Cho, PhD was a post-doctoral fellow at Emory and is currently a research assistant professor at Yonsei University College of Medicine in South Korea. Emory faculty members Rebecca Levit, MD and Hee Cheol Cho, PhD are co-authors on the paper.

Applying a combination of growth factors, regulatory microRNA and vitamins, the Emory researchers could create tissue that contains cardiac muscle, along with blood vessels containing endothelial cells and smooth muscle cells, and fibroblasts. In culture, the four cell types weave themselves together, bypassing any need to build heart tissue from separate components.

When transplanted onto the damaged heart of a mouse after a simulated heart attack, cells from the engineered tissue can migrate into the host heart, and improve its functioning. 

“In some previous studies, when a tissue patch composed of engineered cells and supportive biomaterials was transplanted to the damaged heart, there was little or no migration of cells from the patch to the host heart,” Yoon says.

From Cho et al. Nature Biomed Eng (2021). Migration of rCVT (reprogrammed cardiovascular tissue) into the host heart, 2 weeks after implantation. The white lines outline the heart muscle wall; only the implanted tissue fluoresces green, because of green fluorescent protein.

The critical elements of the direct reprogramming approach are microRNAs, which are “master keys” that control several genes at once. The researchers discovered the potential of one microRNA fortuitously; a pilot study examined the effect of applying several microRNAs active in the heart to fibroblasts. Unexpectedly, one of them generated endothelial cell and smooth muscle along with cardiac muscle cells.

The Emory researchers say that their engineered tissue does not exactly mimic natural heart tissue. The cardiac muscle cells do spontaneously contract, but they display immature characteristics. But after transplantation, the engrafted cells mature and integrate into the host heart. Over 16 weeks, the engrafted cells become indistinguishable from the host cardiac muscle cells. The researchers checked whether their transplanted tissue induced cardiac arrhythmias in the mice – a danger when introducing immature cells into the damaged heart — and they did not.

Yoon says it took almost 9 years to complete the project; an important next step is to test direct reprogramming with human cells.

This work was supported by grants from the National Heart Lung and Blood Institute (R01HL150877, R61HL 154116, R01HL125391) and a American Heart Association Transformative Project Award.

Posted on by Quinn Eastman in Heart Leave a comment

COVID-triggered autoimmunity may be mostly temporary

In people with severe COVID-19, the immune system goes temporarily berserk and generates a wide variety of autoantibodies: proteins that are tools for defense, but turned against the body’s own tissues.

During acute infection, COVID-19 patients’ immune systems resemble those of people with diseases such as lupus or rheumatoid arthritis. However, after the storm passes, the autoantibodies decay and are mostly removed from the body over time, according to a study of a small number of patients who were hospitalized and then recovered. 

In a preprint posted on medRxiv, Emory immunologists provide a view of the spectrum of what COVID-generated autoantibodies react against, both during acute infection and later. Note: the results have not yet been published in a peer-reviewed journal.

The findings on COVID-19-triggered autoimmunity may have implications for both the treatment of acute infection and for long-haulers, in whom autoantibodies are suspected of contributing to persistent symptoms such as fatigue, skin rashes and joint pain.

During acute infection, testing for autoantibodies may enable identification of some patients who need early intervention to head off problems later. In addition, attenuation of autoantibody activity by giving intravenous immunoglobulin (IVIG) – an approach that has been tested on a small scale — may help resolve persistent symptoms, the Emory investigators suggest.

Researchers led by Ignacio Sanz, MD and Frances Eun-Hyung Lee, MD, isolated thousands of antibody-secreting cells from 7 COVID-19 patients who were in ICUs at Emory hospitals. They also looked for markers of autoimmunity in a larger group of 52 COVID-19 ICU patients.

Read more

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Detecting vulnerable plaque with a laser-induced whisper

A relatively new imaging technique called photoacoustic imaging or PAI detects sounds produced when laser light interacts with human tissues. Working with colleagues at Michigan State, Emory immunologist Eliver Ghosn’s lab is taking the technique to the next step to visualize immune cells within atherosclerotic plaques.

The goal is to more accurately spot vulnerable plaque, or the problem areas lurking within arteries that lead to clots, and in turn heart attacks and strokes. A description of the technology was recently published in Advanced Functional Materials

“I believe we are now closer to developing a more precise method to diagnose and treat life-threatening atherosclerotic plaques,” Ghosn says. “Our method could be deployed in combination with IVUS to significantly improve its accuracy and sensitivity, or it could be used non-invasively.”

From science fiction movies, we might think lasers come with a “pow” sound. Photoacoustic imaging is more like listening for a whisper: sounds associated with heat generated by a laser pulse when it is absorbed by tissue.

Earlier this year, the FDA approved a photoacoustic imaging system for detection of breast cancer. Several companies are developing photoacoustic imaging systems, and what we might call “plain vanilla” PAI is currently being tested on carotid artery plaque in clinical studies in Europe.

Ghosn’s approach, developed with biomedical engineer Bryan Smith at Michigan State, adds specificity by adding nanoparticle probes taken up by macrophages, the immune cells that accumulate within atherosclerotic plaques. The nanoparticles, administered before imaging, act as contrast agents.

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Regrowing adult heart muscle

In adulthood, our hearts generally can’t grow again in response to injury. Emory cardiology researchers Ahsan Husain and Nawazish Naqvi and their colleagues have been chipping away at this biological edifice in animal models, demonstrating that it is possible to remove constraints that prevent the heart from growing new muscle cells.

Husain and Naqvi’s teams accomplished this by combining the thyroid hormone T3 — already FDA approved — with siRNA-based inhibition of an enzyme called DUSP5. Their latest paper, published in the journal Theranostics, applies the combination in an animal model of drug-induced heart failure.

The anticancer drug doxorubicin is sometimes known as the “red devil”

The anticancer drug doxorubicin is notorious for its cardiotoxicity, yet it is a mainstay of treatment for breast cancer in adults and several types of cancer in children. Cardiotoxicity affects a fraction of breast cancer patients treated with doxorubicin (20 percent in some studies) and severely impacts mortality and quality of life.

In the mouse model, doxorubicin generates severe heart failure, with a 40 percent drop in left ventricular ejection fraction (LVEF), a measure of the heart’s pumping capacity. In response to the combination of T3 and DUSP5 siRNA, a large increase in LVEF is seen. The researchers also report that the treatment has a marked effect on the health of the animals, restoring their activity levels, grooming and posture. See the video for an example of a mouse heart treated with the T3/DUSP5 siRNA combination.

The results are potentially applicable to other situations when doctors would want to regrow or repair cardiac muscle. Husain reports plans for a clinical study in patients with drug-induced or other forms of heart failure, supported by a generous gift from the Atlanta-based ten Broeke Family Foundation.

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Strengthening SARS-CoV-2 genomic surveillance: support from CDC, private foundations

As part of an effort to strengthen genomic surveillance for emerging strains of SARS-CoV-2, the Centers for Disease Control and Prevention (CDC) has awarded a contract to Emory University researchers to characterize viral variants circulating in Georgia.

The two-year contract is part of the SPHERES (SARS-CoV-2 Sequencing for Public Health Emergency Response, Epidemiology and Surveillance) initiative, with roughly $620,000 in total costs. The principal investigator is Anne Piantadosi, MD, PhD, assistant professor of pathology and laboratory medicine, with co-investigator Mehul Suthar, PhD, assistant professor of pediatrics (infectious diseases).

Both Piantadosi and Suthar are affiliated with Emory University School of Medicine and Emory Vaccine Center. Additional Emory partners include assistant professor of medicine Ahmed Babiker, MBBS, assistant professor of medicine Jesse Waggoner, MD and assistant professor of biology Katia Koelle, PhD.

“We are analyzing SARS-CoV-2 genomes from patients in Georgia to understand the timing and source of virus introduction into our community,” Piantadosi says. “We want to know whether there have been population-level changes in the rates of viral spread, and whether there are associations between viral genotype, viral phenotype in vitro, and clinical phenotype or clinical outcome.”

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Posted on by Quinn Eastman in Immunology, Uncategorized 1 Comment

Repurposing a rheumatoid arthritis drug for COVID-19

For COVID-19, many researchers around the world have tried to repurpose drugs for other indications, often unsuccessfully. New clinical trial results show that baricitinib, developed by Eli Lilly and approved for rheumatoid arthritis, can speed recovery and may reduce mortality in some groups of hospitalized COVID-19 patients.

How did this study, sponsored by the National Institute of Allergy and Infectious Diseases, come together? In part, through decade-long groundwork laid by investigators at Emory, and their collaborations with others.

The ACTT-2 results were recently published in New England Journal of Medicine. (More formal NIAID and Emory press releases are here and here.)

For several years, drug hunter and virologist Raymond Schinazi and his team had been investigating a class of medications called JAK inhibitors, as an option for tamping down chronic inflammation in HIV infection. Schinazi was one of the first at Emory to investigate the use of anti-inflammatory agents for herpesviruses and HIV in combination with antiviral drugs. He believed that these viruses “hit and run,” leaving behind inflammation, even if they later go into hiding and seem to disappear.

In Schinazi’s lab, Christina Gavegnano had shown that JAK inhibitors had both anti-inflammatory and antiviral properties in the context of HIV — a project she started as a graduate student in 2010. JAK refers to Janus kinases, which regulate inflammatory signals in immune cells.

 “Our team was working on this for 10 years for HIV,” Gavegnano says. “There was a huge amount of data that we garnered, showing how this drug class works on chronic inflammation and why.” 

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