New research led by scientists at La Jolla Institute for Immunology (LJI) reveals the workings of a human antibody called mAb 3A6, which may prove to be an important component for Ebola virus therapeutics.
This antibody was isolated from blood samples from an Ebola survivor treated at Emory University Hospital during the 2014-2016 Ebola virus outbreak, an outbreak that began in West Africa and killed more than 11,300 people.
In their new study, the researchers showed that mAb 3A6 helps block infection by binding to an important part of Ebola’s viral structure, called the “stalk.” Study collaborators at the NIH’s National Institute of Allergy and Infectious Diseases (NIAID) found that treatment with mAb 3A6 can benefit non-human primates in advanced stages of Ebola virus disease.
“This antibody offers the best protection in primates, at the lowest dose yet seen for any single antibody,” says LJI Professor, President & CEO Erica Ollmann Saphire, Ph.D., MBA, who led the recent Nature Communications study alongside John A. G. Briggs, Ph.D., of Cambridge University and the Max Planck Institute of Biochemistry; Gabriella Worwa, D.V.M., and Jens H. Kuhn, M.D., Ph.D., of NIAID; and Carl W. Davis, Ph.D., and Rafi Ahmed, Ph.D., of the Emory Vaccine Center.
The discovery that mAb 3A6 appears effective at a very low dose is also exciting. “The lower the amount of an antibody you can deliver to someone, the easier it will be to manufacture a treatment-and the lower the cost,” says study first author Kathryn Hastie, Ph.D., LJI Instructor and Director of LJI’s Center for Antibody Discovery.
How the antibody works
The key to treating Ebola virus is to find antibodies that anchor tightly to and block essential machinery of the virus. The researchers zeroed in on mAb 3A6 because it appears to target a structure on Ebola virus called the “stalk.” The stalk is an important part of the Ebola virus structure because it anchors Ebola’s glycoprotein structure (which drives entry into a host cell) to Ebola’s viral membrane.
The team spearheaded efforts to capture images of mAb 3A6 in action. The researchers used two imaging techniques, called cryoelectron tomography and x-ray crystallography, to show how mAb 3A6 binds to Ebola virus to interrupt the infection process.
The researchers found that mAb 3A6 binds to a site normally concealed by a shifting landscape of viral proteins. “There’s a dynamic movement in these proteins,” says Hastie. “They might kind of wiggle around, move back and forth, maybe lean over a little bit or go up and down.”
Antibody mAb 3A6 takes advantage of this little protein dance. It has such a strong affinity for its viral target that it can slip between the proteins, lift them up, and latch on its target.
Hastie says mAb 3A6’s ability to bind to this target is important for several reasons. First, the site is conserved across different species of Ebola virus, making antibodies that target this region an attractive component in “pan-Ebolavirus” therapeutics. Second, the new understanding of how mAb 3A6 “lifts up” proteins in the viral stalk gives scientists a clearer view of Ebola’s weaknesses. MAb 3A6 also shows us how similar antibodies against the stalks of other viruses might work as well.
This study gives us some hints for how to design vaccines that are specifically against this region of Ebola virus.”
Kathryn Hastie, Ph.D., LJI Instructor and Director of LJI’s Center for Antibody Discovery
Additional authors of the study, “Anti-Ebola virus mAb 3A6 protects highly viremic animals from fatal outcome via binding GP(1,2) in a position elevated from the virion membrane,” include Zhe “Jen” Li Salie, who solved the X-ray structure; Zunlong Ke, who performed the cryoelectron tomography; Lisa Evans DeWald, Sara McArdle, Ariadna Grinyó, Edgar Davidson, Sharon L. Schendel, Chitra Hariharan, Michael J. Norris, Xiaoying Yu, Chakravarthy Chennareddy, Xiaoli Xiong, Megan Heinrich, Michael R. Holbrook, Benjamin Doranz, Ian Crozier, Yoshihiro Kawaoka, Luis M. Branco, Jens H. Kuhn
This study was supported in part by the National Institute of Health’s National Institute for Allergy and Infectious Diseases (grant U19 AI142790, Contract No. HHSN272201400058C, Contract No. HHSN272200700016I, Contract No. HHSN272201800013C), DARPA (contract W31P4Q-14-1-0010), and UK Medical Research Council (grant MC_UP_1201/16), the European Research Council (ERC-CoG-648432 MEMBRANEFUSION), and the Max Planck Society.
Hastie, K. M., et al. (2025). Anti-Ebola virus mAb 3A6 protects highly viremic animals from fatal outcome via binding GP(1,2) in a position elevated from the virion membrane. Nature Communications. doi.org/10.1038/s41467-025-56452-2.
News
Where do nanoparticles go once they enter the body?
New international best practice guidance, co-written at ANSTO, sets out how to measure where nanoparticles like titanium dioxide end up in the body and how long they remain. The guidance has been shared by [...]
Long-Acting HIV Shots Could Solve a Major Treatment Challenge for Young People
A major African trial suggests that changing how HIV treatment is delivered could significantly improve viral suppression in adolescents. Young people with HIV were more likely to keep the virus suppressed when they received [...]
WHO Factsheets – The top 10 causes of death
In 2023, the 10 leading causes of death accounted for 33 million deaths, or 54% of the total 61 million deaths worldwide. The top global causes of death, in order of total number of lives lost, [...]
Aging Cells May Be Hiding From the Immune System – Scientists Think They Know How
Your immune system is supposed to clear out damaged cells. Researchers may have found how some of them hide and linger as the body ages. Researchers led by Cedars-Sinai Health Sciences University have identified [...]
Your Voice May Reveal How Fast Your Brain Is Aging
Researchers have developed a machine-learning “speech clock” that estimates age from subtle patterns in how people speak and what they say. It is possible that people’s voices may contain certain signals of aging that [...]
Optogenetics Pioneers Win 2026 Nobel Prize in Physiology or Medicine
The 2026 Nobel Prize in Physiology or Medicine has been awarded to Peter Hegemann, Georg Nagel, and Karl Deisseroth for the development of optogenetics, a revolutionary technology that uses light to control individual neurons [...]
Molecular Manufacturing: The Future of Nanomedicine – From NanoappsMedical Inc.
This book explores the revolutionary potential of atomically precise manufacturing technologies to transform global healthcare, as well as practically every other sector across society. This forward-thinking volume examines how envisaged Factory@Home systems might enable the cost-effective [...]
What is ‘American Covid’ and how bad is it?
Cases of so-called ‘American Covid’ are on the rise in the UK. The strain is officially called XFG, or ‘Stratus’, and is the most common variant in North America, hence the name. It might soon [...]
Researcher at Russian plague laboratory dies of ‘unknown’ infection
Russian authorities have imposed "anti-epidemic measures" after a laboratory worker at an institute in Siberia dedicated to studying the plague and other infectious diseases died of a mysterious illness. The researcher, a 28-year-old female [...]
GHCE Concept
From the preface of the book Global Health Care Equivalency in the Age of Nanotechnology, Nanomedicine and Artificial Intelligence, Edited by Frank Boehm: Since the publication of my first book (Nanomedical Device and Systems [...]
A Surprising Brain Signal Could Explain Why Eating Less Protein Extends Lifespan
A new paper suggests that limiting protein intake triggers a coordinated response throughout the body that may help explain how protein restriction affects healthy aging. Animals respond to protein restriction, or reduced protein in [...]
Back and shoulder surgery is often worse than useless
Millions of operations should be scrapped SIX IN TEN Britons have surgery at some point. So do lots of Americans, at a cost of perhaps $500bn a year, a third of all spending on [...]
Cocaine plays with mind, hijacks brain circuit, drives increasingly rigid and repetitive behavior
Researchers have found that cocaine hijacks brain circuit, which to drive increasingly rigid and repetitive behavior. The brain circuit that normally participates in selecting natural mouth and face movements, but which becomes disproportionately engaged [...]
Injectable nanodevices could provide effective treatment for drug-resistant glioblastoma
The brain cancer glioblastoma is one of the most aggressive and treatment-resistant cancers known to medicine, carrying a median survival of just 12-15 months, even with the best available care. Now, researchers at the [...]
New Treatment Cuts “Bad” Cholesterol in Half for a Full Year
A single infusion of an experimental CRISPR-Cas9 therapy was reported to safely lower LDL cholesterol by 52.5% and triglycerides by 47.8%, as measured 12 months after treatment. What if one infusion could keep cholesterol [...]
Too Much RNA Can Drain a Cell’s Energy, Scientists Discover
A virus may cripple a cell’s power supply simply by producing too much of a molecule the cell needs to survive. New research from the Texas A&M College of Veterinary Medicine and Biomedical Sciences [...]
