Wayne Drash

Study finds ‘important implications’ to understanding immunity against COVID-19

New research from Emory University indicates that nearly all people hospitalized with COVID-19 develop virus-neutralizing antibodies within six days of testing positive. The findings will be key in helping researchers understand protective immunity against SARS-CoV-2 and in informing vaccine development.

The test that Emory researchers developed also could help determine whether convalescent plasma from COVID-19 survivors can provide immunity to others, and which donors’ plasma should be used.

The antibody test developed by Emory and validated with samples from diagnosed patients has demonstrated that not all antibody tests are created equal – and that neutralizing antibodies, which provide immunity, have specific characteristics. Emory’s study focused on those neutralizing antibodies, which can stop the virus from infecting other cells.

The findings are now available on MedRxiv, the preprint server for health sciences, and are not yet peer-reviewed.

In the study, researchers looked at antibodies against the receptor-binding domain (RBD), part of the spike protein on the outside of the virus. The RBD is what grips on to human cells and allows the virus to enter them. The researchers focused on antibodies against the RBD because the sequence of the RBD in SARS-CoV-2 distinguishes it from other coronaviruses that cause the common cold.

The receptor-binding domain, or RBD, is what grips on to human cells and allows the virus to enter them.

The initial 44 patient blood samples used in this study were from patients being treated for COVID-19 at Emory University Hospital and Emory University Hospital Midtown.

“These findings have important implications for our understanding of protective immunity against SARS-CoV-2, the use of immune plasma as a therapy, and the development of much-needed vaccines,” says Mehul S. Suthar, PhD, co-lead author and assistant professor of pediatrics at Emory University School of Medicine and Emory Vaccine Center. This study serves as the initial step in a much larger serology effort.

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Posted on May 28, 2020 by Wayne Drash in Immunology Leave a comment

Emory plays leading role in landmark HIV prevention study of injectable long-acting cabotegravir

Emory University played a key role in a landmark international study evaluating the safety and efficacy of the long-acting, injectable drug, cabotegravir (CAB LA), for HIV prevention.

The randomized, controlled, double-blind study found that cabotegravir was 69% more effective (95% CI 41%-84%) in preventing HIV acquisition in men who have sex with men (MSM) and transgender women who have sex with men when compared to the current standard of care, daily oral emtricitabine/tenofovir disoproxil fumarate 200 mg and 300 mg (FTC/TDF) tablets.

The study achieved its primary objective of non-inferiority with the difference approaching superiority in favor of cabotegravir, pending final analysis.

The findings were so positive that, during a planned review of study data, an independent Data and Safety Monitoring Board (DSMB) recommended the study results be announced as soon as possible. The study sponsor, the National Institute of Allergy and Infectious Diseases (NIAID), part of the National Institutes of Health, agreed with that recommendation.

Emory, through the Emory-CDC HIV Clinical Trials Unit, enrolled 7% of the study’s more than 4,500 worldwide participants at three of its clinical research sites: The Hope Clinic (86 participants) and the Ponce de Leon Center (35 participants) in Atlanta and at the CDC’s Silom Community Clinic in Bangkok, Thailand (203 participants).

“This is a landmark study with a new approach that will change how HIV prevention is being done and will open the field to future interventions,” says Carlos del Rio, MD, the executive associate dean, Emory University School of Medicine at Grady Health System. Del Rio is a member of the study team and the principal investigator at the Ponce de Leon Center.

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Posted on May 28, 2020 by Wayne Drash in Uncategorized Leave a comment

Yerkes researchers find Zika infection soon after birth leads to long-term brain problems

Researchers from the Yerkes National Primate Research Center have shown Zika virus infection soon after birth leads to long-term brain and behavior problems, including persistent socioemotional, cognitive and motor deficits, as well as abnormalities in brain structure and function. This study is one of the first to shed light on potential long-term effects of Zika infection after birth.

“Researchers have shown the devastating damage Zika virus causes to a fetus, but we had questions about what happens to the developing brain of a young child who gets infected by Zika,” says lead researcher Ann Chahroudi, MD, PhD, an affiliate scientist in the Division of Microbiology and Immunology at Yerkes, director of the Center for Childhood Infections and Vaccines (CCIV), Children’s Healthcare of Atlanta (CHOA) and Emory University, and an associate professor of pediatrics in the Division of Pediatric Infectious Diseases at Emory University School of Medicine.

“Our pilot study in nonhuman primates provides clues that Zika virus infection during the early postnatal period can have long-lasting impact on how the brain develops and works, and how this scenario has the potential to impact child behavior,” Chahroudi continues.

The study, published online in Nature Communications, followed four infant rhesus monkeys for one year after Zika virus infection at one month of age. Studying a rhesus monkey until the age of 1 translates to the equivalent of 4 to 5 years in human age. Researchers found postnatal Zika virus infections led to Impairments in memory function, significant changes in behavior, including reduced social interactions and increased emotional reactions, and some gross motor deficits. These changes corresponded with structural and functional brain changes the researchers found on MRI scans – findings that indicate long-term neurologic complications.

“Our findings demonstrate neurodevelopmental changes detected at 3 and 6 months of age are persistent,” says first author Jessica Raper, PhD, research assistant professor at Yerkes. (See Science Translational Medicine for an earlier study by members of the current research team.) “This is significant because it gives healthcare providers a better understanding of possible complications of Zika beyond infection during pregnancy and into the first years of life,” she adds.
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Posted on May 27, 2020 by Wayne Drash in Neuro Leave a comment

‘Genetic doppelgangers:’ Emory research provides insight into two neurological puzzles

An international team led by Emory scientists has gained insight into the pathological mechanisms behind two devastating neurodegenerative diseases. The scientists compared the most common inherited form of amyotrophic lateral sclerosis and frontotemporal dementia (ALS/FTD) with a rarer disease called spinocerebellar ataxia type 36 (SCA 36).

Both of the diseases are caused by abnormally expanded and strikingly similar DNA repeats. However, ALS progresses quickly, typically killing patients within a year or two, while the disease progression of SCA36 proceeds more slowly over the course of decades. In ALS/FTD it appears that protein products can poison cells in the nervous system. Whether similar protein products exist in SCA36 is not known.

What Zachary McEachin, PhD, and Gary Bassell, PhD, from Emory’s Department of Cell Biology, along with a team of collaborators at Emory, the Mayo Clinic in Jacksonville, Florida, and internationally from Spain and Japan, discovered have provided a new paradigm for thinking about how aberrant protein species are formed.  Regardless of the disparate clinical outcomes between these diseases, this research could broaden the avenue of research toward genetically targeted treatments for such related neurodegenerative diseases.

Their study, published Tuesday in Neuron, provides a guide to types of protein that build up in brain cells in both disorders, and which should be reduced if the new mode of treatment is working in clinical trials.

“We are thinking of these diseases as genetic doppelgängers,” says McEachin, a postdoctoral fellow in Bassell’s lab. “By that, I mean they are genetically similar, but the neurodegeneration progresses differently for each disease. We can use this research to understand each of the respective disorders much better — and hopefully help patients improve their quality of life down the road with better treatments.”

An estimated 16,000 people in the United States have ALS, a progressive neurodegenerative disease that affects nerve cells in the brain and spinal cord. The most common inherited form of ALS/FTD occurs because there is an abnormally expanded repeat of six DNA “letters” stuck into a gene called c9orf72.

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Posted on May 5, 2020 by Wayne Drash in Neuro, Uncategorized Leave a comment

Emory launches study on COVID-19 immune responses

Emory University researchers are taking part in a multi-site study across the United States to track the immune responses of people hospitalized with COVID-19 that will help inform how the disease progresses and potentially identify new ways to treat it.  The study is funded by the National Institute of Allergy and Infectious Diseases (NIAID), part of the National Institutes of Health.

The study – called Immunophenotyping Assessment in a COVID-19 Cohort (IMPACC) – launched Friday. Investigators expect to enroll up to 2,000 individuals who have been hospitalized with the new coronavirus in 10 research locations across the country.

Participants will be followed for up to 12 months after their hospitalization to assess how well they recover and whether they develop durable immunity to the virus.

Nadine Rouphael, associate professor at Emory’s School of Medicine, is leading the investigation as part of NIAID’s Human Immunology Project Consortium (HIPC) and says the study aims to determine how certain immunological measures correspond to or even predict the clinical severity of COVID-19.

“The IMPACC study is a unique opportunity to leverage clinical data and samples with cutting edge technology,” Rouphael says. “By analyzing the immune responses of diverse participants enrolled in the study, we aim to better understand why some cases of COVID-19 worsen while other patients recover.”

As participants recover, investigators will continue evaluating their immune responses to see how they fare: Do they experience lingering symptoms, or do they get long-term protection against the virus? This effort is one of many clinical projects working to better understand how this novel disease affects people differently and determine optimal ways to treat COVID-19.

Researchers will recruit participants within 36 hours of their admission to the hospital and collect blood and nasal swabs throughout their hospitalization, and during follow-up clinic visits after discharge. When possible, researchers will also examine lower airway secretions collected from patients requiring a ventilator for breathing support. Participants can be co-enrolled in other studies, such as those evaluating experimental treatments for COVID-19.

Biologic samples from all study participants will be sent to a number of Core Laboratories for detailed analysis of various aspects of the immune response to the virus that causes COVID-19.

For more information on the U.S. government response to the COVID-19 pandemic, visit www.coronavirus.gov.

Posted on May 1, 2020 by Wayne Drash in Immunology, Uncategorized Leave a comment

Marcus Lab researchers make key cancer discovery

A new discovery by Emory researchers in certain lung cancer patients could help improve patient outcomes before the cancer metastasizes.

The researchers in the renowned Marcus Laboratory identified that highly invasive leader cells have a specific cluster of mutations that are also found in non-small cell lung cancer patients. Leader cells play a dominant role in tumor progression, and the researchers discovered that patients with the mutations experienced poorer survival rates.

The findings mark the first leader cell mutation signature identified in patients and could prove key in teasing out high-risk patients, allowing oncologists to develop a treatment plan early on before the disease has progressed.

“It has been a lot of fun to see the research go from the basic science side inside the lab to hopefully having an actual clinical impact,” says Brian Pedro, an MD/PhD student in Emory’s Medical Scientist Training Program. “Our data suggest that if you have one or more of these mutations, then we could potentially intervene early and improve patient outcomes.”

Stopping leader cells before they metastasize has long been a goal of researchers at the Winship Cancer Institute. “That is what we strive for as researchers,” Pedro says. “We are optimistic that this could be a promising clinical tool.”

The findings were published in the American Cancer Society’s journal “Cancer.”

The researchers specifically found the novel mutation cluster on chromosome 16q and compared the survival rates of those who had the mutations with those who did not. The results showed the patients who had the mutations had poorer survival rates across all stages.

Pedro says more investigation is needed to figure out why the mutations lead to poorer outcomes. He adds that he hopes the mutation signature can prove useful for cancer types beyond lung cancer.

You can learn more from Pedro’s Tweetstorm.

 

Posted on April 28, 2020 by Wayne Drash in Cancer, Uncategorized Leave a comment

Can blood from coronavirus survivors save the lives of others?

Donated blood from COVID-19 survivors could be an effective treatment in helping others fight the illness – and should be tested more broadly to see if it can “change the course of this pandemic,” two Emory pathologists say.

The idea of using a component of survivors’ donated blood, or “convalescent plasma,” is that antibodies from patients who have recovered can be used in other people to help them defend against coronavirus.

Emory pathologists John Roback, MD, PhD and Jeannette Guarner, MD, wrote about the prospects of using the donated blood in a commentary published in JAMA. Their article accompanied a small study in China of five patients on ventilators whose condition improved after they were treated with convalescent plasma.

“Deploying passive antibody therapies against the rapidly increasing number of COIVD-19 cases provides an unprecedented opportunity to perform clinical studies of the efficacy of this treatment against a viral agent,” the two wrote. “If the results of rigorously conducted investigations, such as a large-scale randomized clinical trial, demonstrate efficacy, use of this therapy also could help change the course of this pandemic.”

The patients in Shenzhen were also treated with other antiviral and antiinflammatory agents, and the study was too small to come to definite conclusions. Still, the Emory authors say, the Shenzhen study provides an example of an approach that should be tested on a larger scale. Read more

Posted on March 31, 2020 by Wayne Drash in Immunology, Uncategorized Leave a comment