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
06/10/2025
France T l visions, France's leading broadcaster, has received the 2025 EBU ...
04/09/2025
Monumental Sports & Entertainment (MSE), in collaboration with Dalet, has been a...
30/08/2025
WASHINGTON The Federal Communications Commission has adopted its FY 2025 Regulatory Fees Order that establishes the regulatory fee rates for the broadcast stati...
29/08/2025
Australian Red Cross and SBS launch training to help workplaces in the fight aga...
29/08/2025
The National Film and Video Foundation (NFVF), an agency of the Department of Sp...
29/08/2025
L3Harris Technologies has concentrated decades of expertise across the entire enterprise to develop affordable and reliable best-of-breed solutions to rapidly c...
29/08/2025
BURBANK, Calif. The CW Network and the Pac-12 Conference have announced a new media rights deal that will extend their broadcast partnership beginning with the ...
29/08/2025
NEW YORK Gracenote has released a new analysis of its global video dataset showing that the number of FAST channels grew nearly 14% from Q1 2025 and 76% since 2...
29/08/2025
SAN JOSE, Calif. Harmonic has announced a series of improvements to its live sports streaming solution that the company said will improve fan engagement, protec...
29/08/2025
NEW YORK and LOS ANGELES Fox Corp. and YouTube TV last night announced a renewal of the full portfolio of Fox networks, including Fox News Channel, Fox Business...
29/08/2025
Budapest, Hungary, August 2025 - The integration of Microsoft Teams Rooms (MTR) with Lightware's Taurus universal matrix switchers delivers a new level of f...
29/08/2025
Frequency, the engine behind many of the world's best-known streaming television channels, today announced it will launch Studio Live, a next-generation uni...
29/08/2025
In an era when AI and cyber resilience are essential, Scality will mark the 10th anniversary of Scality Day on October 16, 2025 in Paris. This flagship global e...
29/08/2025
Disguise's In-House Creative and Technical Teams Pre-Visualised, Programmed and Delivered Content for the Experience, All Powered by EX 3+
Technology solu...
29/08/2025
Disguise will be demonstrating the latest workflows for TV, film and live events on a number of partner booths at the show
Disguise, the industry-leading tech...
29/08/2025
STOCKHOLM, Sweden Accedo will showcase Accedo Compose, its AI agent-powered modular orchestration layer that assists streaming providers in transitioning client...
29/08/2025
LOS ANGELES Cineverse has announced that it is working with Xperi to bring four of its streaming channels to automobiles for the first time as part of the DTS A...
29/08/2025
DALLAS & ATLANTA Gray Media has announced an agreement with the sports streaming service Victory+ to simulcast 17 Dallas Stars NHL games in 15 television market...
29/08/2025
NEW YORK AND CULVER CITY Comcast NBCUniversal and Amazon have announced new and extended distribution agreements that will expand the content available on their...
29/08/2025
FOOTHILL RANCH, Calif. RED Digital Cinema will feature its Cine-Broadcast Module supporting live broadcast workflows during IBC2025, Sept. 12-15, at the RAI Ams...
29/08/2025
29 Aug 2025
Kyivstar Rings Opening Bell at Nasdaq Marking Landmark Listing and ...
29/08/2025
More than half of all NFL games live on Sky for the first timeFriday 29 August 2025
Sky Sports has announced a new three-year deal with the NFL, extending its ...
29/08/2025
Back to All News
RIV4LRIES: The Trailer of the New Series With Samuele Carrino ...
29/08/2025
Get ready for an inspiring and emotional insight into the world of competitive Irish dancing with My Story: Tomi Champion of the World airing on RT 2 this monda...
29/08/2025
RT has today announced that David McCullagh is to be the new presenter of RT Radio 1's flagship Today programme, which airs every weekday at 10am, replaci...
28/08/2025
By Kristin Feeley, Director, Documentary Film & Artist Programs
If you want to tell untold stories, if you want to give voice to the voiceless, you've got ...
28/08/2025
Directed by Steven Bognar and Julia Reichert, Sundance Institute-supported Amer...
28/08/2025
Corridos have been a cornerstone of M sica Mexicana for generations, telling stories rooted in everyday life. Now, a new chapter is taking shape: motivational c...
28/08/2025
Los corridos han sido un pilar de la M sica Mexicana durante generaciones, contando historias enraizadas en la vida cotidiana. Ahora, un nuevo cap tulo est tom...
28/08/2025
Earlier this month, we promised our Verano Forever party would bring the heat, a...
28/08/2025
L3Harris will provide the Polish F-16V fleet with the Viper Shield electronic warfare system as part of an upgrade program....
28/08/2025
Bilbao, August 26, 2025 - AgileTV, an international television and video technol...
28/08/2025
Ken Wilkinson is an Emmy Awards nominated New York audio engineer who specialises in production sound mixing for film, commercial, episodic and documentary work...
28/08/2025
NEW YORK FuboTV today announced that it will launch Fubo Sports, a skinny bundle that focuses on sports with a subscription price of $56 monthly....
28/08/2025
NEVADA City, Calif. At IBC2025, Sept. 12-15 at the RAI Amsterdam, Telestream will debut its new Global Ingest strategy, introducing a next-generation ingest arc...
28/08/2025
Dr. Rhoda Bernard Releases Groundbreaking Debut Book on Accessible Arts Educatio...
28/08/2025
TAG Video Systems, the leader in software-based IP end-to-end workflow monitoring, deep probing, and real-time visualization, has named Oliver Gappa as Sales Di...
28/08/2025
AI-based voice enhancement will be among a series of innovations making their IBC 2025 debut on the DHD stand B46 in Hall 8 at the RAI Amsterdam Convention Cent...
28/08/2025
Telef nica Servicios Audiovisuales (TSA), the leading system integrator and service provider in the media sector in Spain, with the support of Appear, the globa...
28/08/2025
To fully immerse sailing fans in the world's biggest offshore yacht race, production company, Optical Media turned to LiveU's On-site Production solutio...
28/08/2025
Working with Calrec on its most recent overhaul, radio and television broadcaster, WNED has migrated to a fully IP infrastructure with multiple Type R consoles,...
28/08/2025
Cleeng, the Subscriber Retention Management (SRM ) inventor, has unveiled Cleeng Pro, the first-ever direct-to-consumer (D2C) subscription management platform t...
28/08/2025
Zixi, the industry leader in live broadcast-quality video over IP, today announced that French media distribution platform OKAST has selected Zixi to enable rel...
28/08/2025
Solution offers a streamlined, speaker-free architecture to optimize integration with premium external loudspeakers and advanced loudness metering
Nixer Pro Au...
28/08/2025
Cinegy, the premier provider of software-defined television technology, has announced a strategic partnership with Vision One Touch Film Production Services L.L...
28/08/2025
Telestream, a global leader in media workflow technologies, will debut its new Global Ingest strategy at IBC2025, introducing a next-generation ingest architect...
28/08/2025
Tier 1 operator selects Broadpeak to power high-performance, unified CDN solution across Norway, Sweden and Finland
Broadpeak, a leader in streaming and moneti...
28/08/2025
Leading video software provider, Synamedia, today announced that 24 Frames Digital, one of India's leading live event streaming service providers, has chose...
28/08/2025
Meet VisualOn at IBC2025: See What's Next in AI-Powered Video Streaming Join VisualOn at IBC2025 and discover how our AI-driven Optimizer and advanced media...
Experimental HIV vaccine successfully elicits broadly neutralizing antibodies to the virus Vaccinated rabbits produce antibodies to at least two vulnerable sites on HIV.
