Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

AIDS vaccine delivers

17.01.2002


The HIV virus: killing cells laden with these particles may form a key part of future AIDS vaccination strategies.
© SPL


Cellular attack tactic keeps virus at bay.

A new AIDS vaccine could be one of the most promising yet. The drug’s effects in monkeys suggest that killing virus-laden cells may form a key part of future vaccination strategies.

Vaccinated monkeys survived a usually lethal infection with a monkey-human hybrid virus, SHIV. Their primed immune system kept virus levels below detection, Emilio Emini of Merck Research Laboratories in West Point, Pennsylvania, and his team now report1. The results are some of the most encouraging to come out of AIDS vaccine research.



But doubts have already been voiced. Low-lying virus can change to elude the immune response, argue Dan Barouch of Harvard Medical School in Boston and his team. A year after they gave eight animals a similar vaccination, a mutant form of the virus emerged, killing one of the monkeys2.

"This finding should be a reality check rather than a death knell," Barouch says, adding that the technique can be modified to block the emergence of mutant viruses. Future attempts could hit several different SIV proteins to prevent the virus escaping. Both of the latest vaccines targeted a single protein.

Emini is already pursuing this goal. But like multi-drug-resistant bacteria, HIV could conceivably outwit even a broadly targeted vaccine, although this is less likely. Whether the vaccines tested in the monkeys will be as effective in humans, however, is unknown.

Troubled history

AIDS is notoriously difficult to vaccinate against. Initial attempts took a conventional approach by injecting a single HIV surface protein to trigger the animals’ immune system into producing antibodies that would attack the virus during a subsequent infection. But HIV evades antibodies by hiding the proteins that the antibodies latch onto and by evolving new strains.

"HIV turned out to be much more complicated," says vaccine researcher Jeffrey Lifson of the National Cancer Institute at Frederick, Maryland. In the past few years, vaccine hunters have switched to a different tack that simulates the way the body naturally attempts to deal with HIV infection - namely, stimulating the immune system to strike virus-infected cells.

Emini’s team achieved this by using a harmless virus to deliver SIV DNA direct to specific immune cells. "It looks encouraging," says Lifson.

Unfortunately, as with any vaccine that keeps virus levels in check, rather than preventing infection, there is the risk that the pathogen will re-emerge. "It’s an ominous question to ask about the whole strategy," comments Lifson. Nonetheless, such a vaccine could in theory defer the onset of AIDS and cut the risk of HIV spreading.

The antibody approach may still bear fruit if it can hit essential, unchanging parts of the virus. Meanwhile, the ultimate ideal remains a vaccine that triggers both arms of the immune system - antibodies and cell attack.

References

  1. Shiver, J. W. et al. Replication-incompetent adenoviral vaccine vector elicits effective anti-immunodeficiency-virus immunity. Nature, 415, 331 - 335, (2002).
  2. Barouch, D. H. et al. Eventual AIDS vaccine failure in a rhesus monkey by viral escape from cytotoxic T lymphocytes. Nature, 415, 335 - 339, (2002).

HELEN PEARSON | © Nature News Service

More articles from Health and Medicine:

nachricht Building blocks for new medications: the University of Graz is seeking a technology partner
19.03.2019 | Karl-Franzens-Universität Graz

nachricht Scientists find new approach that shows promise for treating cystic fibrosis
14.03.2019 | NIH/National Heart, Lung and Blood Institute

All articles from Health and Medicine >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Stellar cartography

The Potsdam Echelle Polarimetric and Spectroscopic Instrument (PEPSI) at the Large Binocular Telescope (LBT) in Arizona released its first image of the surface magnetic field of another star. In a paper in the European journal Astronomy & Astrophysics, the PEPSI team presents a Zeeman- Doppler-Image of the surface of the magnetically active star II Pegasi.

A special technique allows astronomers to resolve the surfaces of faraway stars. Those are otherwise only seen as point sources, even in the largest telescopes...

Im Focus: Heading towards a tsunami of light

Researchers at Chalmers University of Technology and the University of Gothenburg, Sweden, have proposed a way to create a completely new source of radiation. Ultra-intense light pulses consist of the motion of a single wave and can be described as a tsunami of light. The strong wave can be used to study interactions between matter and light in a unique way. Their research is now published in the scientific journal Physical Review Letters.

"This source of radiation lets us look at reality through a new angle - it is like twisting a mirror and discovering something completely different," says...

Im Focus: Revealing the secret of the vacuum for the first time

New research group at the University of Jena combines theory and experiment to demonstrate for the first time certain physical processes in a quantum vacuum

For most people, a vacuum is an empty space. Quantum physics, on the other hand, assumes that even in this lowest-energy state, particles and antiparticles...

Im Focus: Sussex scientists one step closer to a clock that could replace GPS and Galileo

Physicists in the EPic Lab at University of Sussex make crucial development in global race to develop a portable atomic clock

Scientists in the Emergent Photonics Lab (EPic Lab) at the University of Sussex have made a breakthrough to a crucial element of an atomic clock - devices...

Im Focus: Sensing shakes

A new way to sense earthquakes could help improve early warning systems

Every year earthquakes worldwide claim hundreds or even thousands of lives. Forewarning allows people to head for safety and a matter of seconds could spell...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

VideoLinks
Industry & Economy
Event News

International Modelica Conference with 330 visitors from 21 countries at OTH Regensburg

11.03.2019 | Event News

Selection Completed: 580 Young Scientists from 88 Countries at the Lindau Nobel Laureate Meeting

01.03.2019 | Event News

LightMAT 2019 – 3rd International Conference on Light Materials – Science and Technology

28.02.2019 | Event News

 
Latest News

Levitating objects with light

19.03.2019 | Physics and Astronomy

New technique for in-cell distance determination

19.03.2019 | Life Sciences

Stellar cartography

19.03.2019 | Physics and Astronomy

VideoLinks
Science & Research
Overview of more VideoLinks >>>