Experimental HIV vaccine successfully elicits broadly neutralizing antibodies to the virus Vaccinated rabbits produce antibodies to at least two vulnerable sites on HIV.
November 18, 2019
LA JOLLA, CA An experimental HIV vaccine developed by scientists at Scripps Research and the nonprofit vaccine research organization IAVI has reached an important milestone by eliciting antibodies that can neutralize a wide variety of HIV strains.
The tests, in rabbits, showed that these broadly neutralizing antibodies, or bnAbs, targeted at least two critical sites on the virus. Researchers widely assume that a vaccine must elicit bnAbs to multiple sites on HIV if it is to provide robust protection against this ever-changing virus.
The promising results, which appear in Immunity, suggest that researchers are one step closer to developing an effective HIV vaccine a major goal of medical science ever since the virus was identified in 1983.
It's an initial proof of principle but an important one, and we're now working to optimize this vaccine design, says the study's senior author Richard Wyatt, PhD, a professor in the Department of Immunology and Microbiology at Scripps Research.
According to UNAIDS, about 35 million people worldwide have died of the immunodeficiency syndrome, AIDS, which is caused by HIV infection. About 38 million others are now living with HIV infection. Antiviral drugs can keep HIV-infected people alive and reduce their ability to transmit the virus to others, but these drugs do not clear the infection and must be taken indefinitely. Researchers have long recognized that a preventive vaccine, available at a low cost to uninfected people, will be needed to eliminate HIV as a major public health threat.
HIV's rapid mutation rate and other mechanisms for evading immune attack have made it an extremely difficult target for vaccine designers. But the test conducted by Wyatt and his team confirms that vaccination can elicit the kinds of antibodies that are needed to provide broad protection against HIV. These bnAbs, as vaccine experts call them, can neutralize multiple HIV strains because they bind to critical sites on the virus that do not vary much from strain to strain. People who are infected with HIV sometimes produce bnAbs as part of their antibody response, but infrequently and usually after infection has been long established. The chief challenge for HIV vaccine designers has been to find ways to stimulate the immune system in most or all individuals into making bnAbs that hit multiple vulnerable sites on the virus, in order to protect against a high proportion of HIV strains.
At the heart of the vaccine design by Wyatt and colleagues is a virus-mimicking protein based on HIV's Env protein. Normally, multiple copies of bush-like Env proteins are spread out on the surface of each spherical HIV particle. Each Env protein contains a molecular mechanism that allows it to bind to a receptor on immune cells known as CD4, and use that receptor as a portal to break into the cell. The researchers engineered a version of Env that models the essential structures on the real Env while being stable enough to use as a vaccine. To present it in a way that would resemble a real HIV virus particle, they created virus-sized synthetic spheres of fat-related molecules, liposomes, which are studded densely with the engineered Env proteins.
On a natural HIV Env protein, thickets of sugar-related molecules called glycans normally help shield the all-important CD4 binding site from immune attack. As an initial priming immunization, the researchers used versions of Env in which this glycan shield around the CD4 binding site had been partly removed.
The idea was to better expose this site and thereby stimulate a broad antibody reaction to it at the start, Wyatt says.
Subsequent booster immunizations over 48 weeks used Env proteins with restored glycans, to select for antibodies that target the CD4 binding site but can also get through this shield. The Env proteins in the booster shots also were mixes based on different strains of HIV, to generally promote antibody responses against Env structures that do not vary among these strains.
The team inoculated 12 rabbits following their vaccine strategy and compared the results with a control group that received only a single, glycan-shielded version of Env. They found that their vaccine strategy had a much better response, with five of the rabbits developing antibodies that could neutralize multiple HIV isolates.
The researchers analyzed the antibodies of the rabbit that had responded most strongly, and identified two distinct types of bnAb. One, which they called E70, blocks the CD4 binding site as expected, though in an unusual way partly by grabbing one of the shielding glycans. The other, 1C2, hits a different but well known vulnerable spot on Env, at the interface between two key segments of the complex protein. The binding of antibody 1C2 apparently destabilizes Env so that it can no longer mediate HIV's entry into host cells. That antibody also turned out to have an unusual breadth of neutralization, blocking 87 percent of a panel of 208 distinct HIV isolates.
The finding is an important demonstration that vaccination against HIV, if done in the right way, can achieve the goal of inducing bnAbs to multiple sites on the virus, Wyatt says.
The team of scientists are continuing to test and improve their vaccine strategy in small animal models and hope eventually to test it in monkeys and then humans.
The co-lead authors of the study, Vaccination with Glycan-Modified HIV NFL Envelope Trimer-Liposomes Elicits Broadly Neutralizing Antibodies to Multiple Sites of Vulnerability, were Viktoriya Dubrovskaya, PhD, and Gabriel Ozorowski, PhD, of Scripps Research and Karen Tran, PhD, of the IAVI Neutralizing Antibod
Most recent headlines
17/12/2025
Share Share by:
Copy link
Facebook
X
Whatsapp
Pinterest
Flipboard...
17/12/2025
Share Share by:
Copy link
Facebook
X
Whatsapp
Pinterest
Flipboard...
17/12/2025
Share Share by:
Copy link
Facebook
X
Whatsapp
Pinterest
Flipboard...
17/12/2025
Share Share by:
Copy link
Facebook
X
Whatsapp
Pinterest
Flipboard...
17/12/2025
Share Share by:
Copy link
Facebook
X
Whatsapp
Pinterest
Flipboard...
17/12/2025
Share Share by:
Copy link
Facebook
X
Whatsapp
Pinterest
Flipboard...
17/12/2025
Share Share by:
Copy link
Facebook
X
Whatsapp
Pinterest
Flipboard...
17/12/2025
KPop Demon Hunters Stars Visit Berklee for Weeklong Celebration Andrew Choi and EJAE, who voiced the film's main characters and contributed to its soundtr...
16/12/2025
Hawkins has landed on Spotify, just in time for Stranger Things Season 5, Volume...
16/12/2025
Wherever you are, your favorite music and audio content should go seamlessly with you. That's why Spotify has partnered with NAVER Corp, Korea's leading...
16/12/2025
2025 Wrapped arrived bigger and bolder than ever. This year's experience is designed to be ultra personal and shareable, with new features like Wrapped Part...
16/12/2025
Three 12-kilowatt Advanced Electric Propulsion System thrusters, supplied by L3Harris Technologies, form the core of Gateway's propulsion system. Pictured i...
16/12/2025
The challenge facing America's defense industrial base is not just about speed - its about rebuilding the foundation that makes speed possible. Our nations ...
16/12/2025
Share Share by:
Copy link
Facebook
X
Whatsapp
Pinterest
Flipboard...
16/12/2025
SEVILLE, Spain Canal Sur, the public broadcasting service for Andalusia, Spain, has completed a total technology refresh based on Pebble's resilient, softwa...
16/12/2025
NEW YORK Teleprompting hardware provider Telescript International has acquired all software code and intellectual property previously owned by Telescript West. ...
16/12/2025
As cable operators face increased competition from 5G fixed wireless access providers, a new report from Ookla Research finds that T-Mobile is the FWA speed lea...
16/12/2025
Apple has announced a major upgrade to the Apple TV app for device owners outside the Apple ecosystem with news that the Apple TV app for Android now supports G...
16/12/2025
Space42 grows Direct-to-Device partner ecosystem through a Memorandum of Underst...
16/12/2025
16 Dec 2025
VEON Announces Release Date for Full Year and Fourth Quarter 2025 R...
16/12/2025
16 Dec 2025
VEON's Kyivstar Invests in Renewable Energy in Ukraine with Acq...
16/12/2025
Back to All News
Emma Appleton, Fares Fares, Frida Gustavsson and Jakob Oftebro...
16/12/2025
Back to All News
Docu-reality My Korean Boyfriend Gets a Trailer and Premiere D...
16/12/2025
Harmonic's XOS Advanced Media Processor Improves Streaming Video Quality and Boosts Viewer Engagement SAN JOSE, Calif. - Dec. 16, 2025 - Harmonic (NASDAQ: ...
16/12/2025
RT Sport Awards 2025 live on RT One and RT Player at 8:05pm on Saturday 20 December.
On Saturday 20 December live on RT One and RT Player at the earlier t...
16/12/2025
Singer -songwriter Brian Kennedy has been announced as the final celebrity dance...
15/12/2025
Harlem Globetrotters Celebrate 100th Anniversary With New Brand Campaign From Th...
15/12/2025
Top L-R: La Tierra Del Valor (The Home of the Brave), Mangittatuarjuk (The Gnawe...
15/12/2025
L3Harris will leverage 15 years of experience supporting the E-4B Nightwatch and...
15/12/2025
CONWAY, Ark. In a notable example of how the loss of federal funding is forcing public stations to make massive cuts and operational changes, the statewide pub...
15/12/2025
BOULDER, Colo. Public Media Venture Group (PMVG), Venture Technologies Group (VTG), and WQED have completed a multipart agreement that they say will significant...
15/12/2025
Cape Town, November 13, 2025 - SES and International artist and humanitarian, Fo...
15/12/2025
Luxembourg, December 15, 2025 - SES, a leading space solutions company, and Abra Group launched fast and reliable multi-orbit inflight connectivity service on t...
15/12/2025
How Rivian s Design Puts Drivers First-And Why That Matters Published on Dec 15, 2025 Categories: Business Solutions
LinkedIn Corporate Communications
Sha...
15/12/2025
Space42 and Cobham Satcom completed the full range of advanced terminals for the...
15/12/2025
15 Dec 2025
VEON's Beeline Kazakhstan Delivers First Starlink Direct to Cel...
15/12/2025
Andrew Mountbatten-Windsor finds himself the topic of year's cracker jokes
Oasis, David Harbour, Celebrity Traitors and Angela Rayner all feature in this y...
15/12/2025
Comscore Expands Cross-Platform Campaign Measurement to Include Audio and Social New capabilities strengthen cross-platform campaign reporting suite; CCR rebran...
15/12/2025
NVIDIA today announced it has acquired SchedMD - the leading developer of Slurm, an open-source workload management system for high-performance computing (HPC) ...
15/12/2025
RT .ie has reached one billion page views this year and is on track to finish 2025 2% ahead of last year. Average time spent on the site is up 3% on 2024, with ...
15/12/2025
Modern workflows showcase the endless possibilities of generative and agentic AI on PCs.
Of many, some examples include tuning a chatbot to handle product-supp...
13/12/2025
Powering Client Growth: Horizon Deepens Nielsen Partnership, Enabling More Effic...
13/12/2025
In a move that will help it offer more flexible and less costly programming options, YouTube TV has announced that it will be launching YouTube TV Plans with mo...
13/12/2025
SINGAPORE Magna Systems has designed, built and completed what is believed to be the first full UHD and IP-based OB truck in Southeast Asia for a Singapore medi...
12/12/2025
SVG Summit 2025 Preview: Everything You Need to Know for Next Week's Big Sho...
12/12/2025
Hailey Gates at the Atropia premiere (photo by George Pimentel / Shutterstock for Sundance Film Festival)...
12/12/2025
Last month, Spotify announced a new collaboration with the ATP Tour, the global governing body of men's professional tennis, aimed at bringing the next gene...
12/12/2025
CONWAY, Ark. In a notable example of how the elimination of Federal federal funding is forcing public stations to make massive cuts and changes in the way they...
12/12/2025
Wisycom and DPA Microphones announce the appointment of Ren Moerch as Group Product Director, Wireless, a strategic leadership role that will guide the combine...
Experimental HIV vaccine successfully elicits broadly neutralizing antibodies to the virus Vaccinated rabbits produce antibodies to at least two vulnerable sites on HIV.
